Wednesday, February 28, 2018
Must Eat Food in Sunway Pyramid
Thursday, February 22, 2018
Marmite Chicken
Ingredient:
250 ml oil for deep-frying
2 chicken thighs, about 500g cut into pieces
Marinade:
1 tsp light soya sauce
1/2 tsp salt
1/2 tsp pepper
1 tbsp corn flour
Sauce:
2 tbsp Marmite yeast extract
1 tbsp maltose
1 tbsp honey
1 tbsp light soya sauce
Dash of pepper
Chicken stock granules
100ml water
Method:
1. Mix the chicken with the marinade and season for 1 hour.
2, Deep fry in hot oil for 2 minutes or until cooked. Dish up and drain the excess oil.
3. Leave 1 tbsp oil in the wok, pour in the sauce and cook at medium heat until thick. Put in fried chicken and mix well. Dish up and serve.
Note: This recipe can be use to prepare spare rips or prawns too. However, do not marinade the prawns before frying.
250 ml oil for deep-frying
2 chicken thighs, about 500g cut into pieces
Marinade:
1 tsp light soya sauce
1/2 tsp salt
1/2 tsp pepper
1 tbsp corn flour
Sauce:
2 tbsp Marmite yeast extract
1 tbsp maltose
1 tbsp honey
1 tbsp light soya sauce
Dash of pepper
Chicken stock granules
100ml water
Method:
1. Mix the chicken with the marinade and season for 1 hour.
2, Deep fry in hot oil for 2 minutes or until cooked. Dish up and drain the excess oil.
3. Leave 1 tbsp oil in the wok, pour in the sauce and cook at medium heat until thick. Put in fried chicken and mix well. Dish up and serve.
Note: This recipe can be use to prepare spare rips or prawns too. However, do not marinade the prawns before frying.
Salted Fish and Pork Belly in Clay Pot
Ingredients:
1 tbsp oil
50 g salted fish, diced
3 dried chilli, cut into 3 cm length
15 slices of ginger
1 onion, sliced
300g pork belly, sliced thinly
1 tbsp oil
3 stalks of spring onion, cut into 3 cm length
Seasoning:
1/2 tbsp light soya sauce
1 tsp sugar
1 tsp oyster sauce
1 tsp dark soya sauce
1 tbsp shaoxing wine
100ml water
Method:
1. Heat up the oil and saute the salted fish and dried chilli at low heat until fragrant.
2. Add in the ginger, onion and pork belly and stir well. Add in the seasoning, stir well and cook for 3 minutes until meat is tender.
3. Heat up a clay pot, add in 1 tbsp oil and saute the spring onion until fragrant. Add in the pork belly mixture, 1 tbsp shaoxing wine and cover the lid. Simmer for another 1-2 minutes until fragrant. Serve immediately.
Notes: Chill the meat in the fridge until slightly firm for easy slicing into thin pieces. Use "Mui Hiong" salted fish for better flavour.
Creamy Curry Chicken
Ingredients:
2 chicken whole legs, cut into pieces
3 tbsp oil
5 pips garlic, peeled and cut into small pieces
1 onion, peeled and cit into small pieces
2 stalks lemongrass, crushed
2 red chillies, seeded and cut into pieces
3 pieces kaffir lime leaf
Seasoning:
1 tsp salt
1 tsp curry powder
1 tsp sugar
100ml water
100 ml evaporated milk
Method:
1. Heat up the oil and pan-fry the chicken pieces until lightly brown and fragrant then dish up.
2. Leave 1 tbsp oil in the wok, saute the garlic and onion until aromatic. Add in the remaining ingredients and stir-fry until fragrant.
3. Add in chicken and seasoning. Cover with lid and cook for 10 minutes at medium low heat.
4. Add the evaporated milk and bring to a boil. Dish up and serve.
Note: Be sure to add in the evaporated milk last to ensure that it does not turn into fats.
2 chicken whole legs, cut into pieces
3 tbsp oil
5 pips garlic, peeled and cut into small pieces
1 onion, peeled and cit into small pieces
2 stalks lemongrass, crushed
2 red chillies, seeded and cut into pieces
3 pieces kaffir lime leaf
Seasoning:
1 tsp salt
1 tsp curry powder
1 tsp sugar
100ml water
100 ml evaporated milk
Method:
1. Heat up the oil and pan-fry the chicken pieces until lightly brown and fragrant then dish up.
2. Leave 1 tbsp oil in the wok, saute the garlic and onion until aromatic. Add in the remaining ingredients and stir-fry until fragrant.
3. Add in chicken and seasoning. Cover with lid and cook for 10 minutes at medium low heat.
4. Add the evaporated milk and bring to a boil. Dish up and serve.
Note: Be sure to add in the evaporated milk last to ensure that it does not turn into fats.
Fried Pork Belly with Lemongrass & Shallots
Ingredients:
500g pork belly, cut into slices
3 tbsp oil
5 shallots, peeled and sliced
2 stalk lemongrass, shredded
1 red chilli, seeded and shredded
Marinade
1/2 tsp salt
Dash of pepper
1 tsp cornstarch
Seasoning
2 tbsp light soya sauce
1 tbsp oyster sauce
1/2 tbsp sugar
3 tbsp water
Method:
1. Mix the pork belly with the marinade and season for 30 minutes
2. Heat up the oil and pan-fry the pork belly until both sides are golden brown. Dish up
3. Add the shallots, lemongrass, red chilli and stir-fry until aromatic. Add the seasoning, pork belly and stir well. Continue to cook until the sauce has thickened.
4. Dish up and serve.
500g pork belly, cut into slices
3 tbsp oil
5 shallots, peeled and sliced
2 stalk lemongrass, shredded
1 red chilli, seeded and shredded
Marinade
1/2 tsp salt
Dash of pepper
1 tsp cornstarch
Seasoning
2 tbsp light soya sauce
1 tbsp oyster sauce
1/2 tbsp sugar
3 tbsp water
Method:
1. Mix the pork belly with the marinade and season for 30 minutes
2. Heat up the oil and pan-fry the pork belly until both sides are golden brown. Dish up
3. Add the shallots, lemongrass, red chilli and stir-fry until aromatic. Add the seasoning, pork belly and stir well. Continue to cook until the sauce has thickened.
4. Dish up and serve.
Wednesday, February 21, 2018
Crispy Almond Meringue Cake
Recipe taken and improvised from Food & Fam
Click here to see the original recipe
Notes: I added a layer of chocolate ganache between each meringue and whipped cream layer. The meringue is only crispy on the outside and soft on the inside. It sticks to the parchment layer (remember to coat with flour). To assemble easily, use a cheesecake tin can and remove after refrigerating.
Ingredients
Meringue Layers:
10 egg whites (from large eggs)
1¾ cups granulated sugar, plus 1 tablespoon
½ pound blanched almonds (8 oz)
1 tablespoon cornstarch
Fresh Vanilla Whipped Cream:
3 cups heavy cream
1 teaspoon vanilla
¼ cup powdered sugar
1/2 cup granulated sugar
Chocolate ganache
8 oz semi sweet chocolate chips
1 cup heavy whipping cream
Topping: (optional)
8 ounces dark chocolate, chopped
Chocolate jimmies/sprinkles, or more chopped chocolate
Instructions
Meringue layers:
Preheat oven to 250 degrees.
Pour the blanched almonds in your food processor and grind them down until they look like small crumbs.
Beat egg whites with your mixer on medium-high until they start to foam. Gradually add ¾ of a cup plus one tablespoon of sugar to the mix until it forms stiff peaks.
In a small bowl, combine 1 cup of sugar and the cornstarch.
Fold the cornstarch mixture and ground almonds carefully into the beaten eggs until everything is well-incorporated.
Put 1 cup of batter into a pastry bag and pipe out four 10-inch circles (I use a tart pan or springform pan base as a template for consistency). Then, using a spreader, fill in the circles until you have nice even discs of batter.
Bake the meringue layers for 1.5 hours. Remove from oven and let cool.
Chocolate ganache:
Bring heavy cream to a simmer on a stove.
Pour into the chocolate chips.
Wait for 10 minutes.
Stir using a spoon.
If it does not melt, put the mixture on top of a small fire stove and stir constantly. Make sure the heat is not on high.
Fresh Vanilla Whipped Cream:
Mix the cream and granulated sugar on high until peaks begin to form. Add vanilla while mixing.
Add powdered sugar and mix until the whipped cream until it is thick and slightly stiff.
Assembling the Cake:
Start with a meringue layer and top it with whipped cream about ¼" thick. Continue to alternate meringue layers and whipped cream, and then coat the top and outside of cake with whipped cream.
Use your hand and press sprinkles or chocolate into the sides of the cake, then sprinkle chopped chocolate generously on the top of the cake.
You can serve this immediately, but I recommend refrigerating it for about 30 minutes to help it set.
Click here to see the original recipe
Notes: I added a layer of chocolate ganache between each meringue and whipped cream layer. The meringue is only crispy on the outside and soft on the inside. It sticks to the parchment layer (remember to coat with flour). To assemble easily, use a cheesecake tin can and remove after refrigerating.
Ingredients
Meringue Layers:
10 egg whites (from large eggs)
1¾ cups granulated sugar, plus 1 tablespoon
½ pound blanched almonds (8 oz)
1 tablespoon cornstarch
Fresh Vanilla Whipped Cream:
3 cups heavy cream
1 teaspoon vanilla
¼ cup powdered sugar
1/2 cup granulated sugar
Chocolate ganache
8 oz semi sweet chocolate chips
1 cup heavy whipping cream
Topping: (optional)
8 ounces dark chocolate, chopped
Chocolate jimmies/sprinkles, or more chopped chocolate
Instructions
Meringue layers:
Preheat oven to 250 degrees.
Pour the blanched almonds in your food processor and grind them down until they look like small crumbs.
Beat egg whites with your mixer on medium-high until they start to foam. Gradually add ¾ of a cup plus one tablespoon of sugar to the mix until it forms stiff peaks.
In a small bowl, combine 1 cup of sugar and the cornstarch.
Fold the cornstarch mixture and ground almonds carefully into the beaten eggs until everything is well-incorporated.
Put 1 cup of batter into a pastry bag and pipe out four 10-inch circles (I use a tart pan or springform pan base as a template for consistency). Then, using a spreader, fill in the circles until you have nice even discs of batter.
Bake the meringue layers for 1.5 hours. Remove from oven and let cool.
Chocolate ganache:
Bring heavy cream to a simmer on a stove.
Pour into the chocolate chips.
Wait for 10 minutes.
Stir using a spoon.
If it does not melt, put the mixture on top of a small fire stove and stir constantly. Make sure the heat is not on high.
Fresh Vanilla Whipped Cream:
Mix the cream and granulated sugar on high until peaks begin to form. Add vanilla while mixing.
Add powdered sugar and mix until the whipped cream until it is thick and slightly stiff.
Assembling the Cake:
Start with a meringue layer and top it with whipped cream about ¼" thick. Continue to alternate meringue layers and whipped cream, and then coat the top and outside of cake with whipped cream.
Use your hand and press sprinkles or chocolate into the sides of the cake, then sprinkle chopped chocolate generously on the top of the cake.
You can serve this immediately, but I recommend refrigerating it for about 30 minutes to help it set.
Tuesday, February 20, 2018
Bahasa Istana
1. marah- murka
2. makan- santap
3. tidur- beradu
4. mandi- bersiram
5. berjalan- mecemar duli
6. sakit- gering
7, bersuara- bertitah
8. hadiah- anugerah
9. mati- mangkat
10. isteri- permaisuri
11. kerusi- singgahsana
12. rumah- istana
13. dikuburkan- dimakamkan
14. hari lahir- hari keputeraan
15. bertolak- berangkat
16. suka/ sudi- berkenan
17. duduk- bersemayam
18. memberi salam- menyembah
19. kasut- kaus
20. saya- beta
21. terima kasih- junjung kasih
22. maaf- ampun kurnia
23. bahagia- daulat
24. menjumpai- menghadap
25. bersalin- berputera
26. ayah- paduka ayahanda
27. ibu- paduka bonda
28.
2. makan- santap
3. tidur- beradu
4. mandi- bersiram
5. berjalan- mecemar duli
6. sakit- gering
7, bersuara- bertitah
8. hadiah- anugerah
9. mati- mangkat
10. isteri- permaisuri
11. kerusi- singgahsana
12. rumah- istana
13. dikuburkan- dimakamkan
14. hari lahir- hari keputeraan
15. bertolak- berangkat
16. suka/ sudi- berkenan
17. duduk- bersemayam
18. memberi salam- menyembah
19. kasut- kaus
20. saya- beta
21. terima kasih- junjung kasih
22. maaf- ampun kurnia
23. bahagia- daulat
24. menjumpai- menghadap
25. bersalin- berputera
26. ayah- paduka ayahanda
27. ibu- paduka bonda
28.
Lab report: Thermoregulation in animals
Introduction:
Living organisms exist in habitats where the temperature ranges from 115 C in volcanic vents to -40 C at the poles. An organism’s temperature varies according to the amount of heat it gains and the amount of heat it loses. If heat gain is greater than heat loss, the temperature of the organism will rise and vice versa. To maintain a stable body temperature, an organism needs to balance its heat gain with its heat loss. Thermoregulation is the process by which animals maintain an internal temperature within a tolerable range. It contributes to homeostasis and involves anatomy, physiology and behavior. The experiment is conducted to study the effects of exercise on the breathing rate and body temperature of a human. It can be done by measuring the number of breathing rate during resting state an after a workout. Breathing rate is also known as respiration rate. It is measured by counting the number of breathes for one minute by counting the number of times the chest rises. For adults, the normal breathing rate is 12-18 breaths per minute. People who are ill, such as those with lung or heart disease, may have a change in breathing rate. Other factors that may affect breathing rates are carbon dioxide and concentration which causes a change in pH value of the blood. Carbon dioxide concentration may increase during exercises which use a lot of energy. The rate of respiration increases to provide more energy for the body to do work. This results in an increase in CO2 level as glucose is broken down into ATP and CO2. Drugs and alcohol such as narcotic pain reliever and sedative may depress the activity of the respiratory system. On the other hand, the temperature of the student is also measured before and after the workout using a thermometer.
Most body heat is generated in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles. Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the human body, placing it in great danger of injury or even death. For humans, adaptation to varying climatic conditions includes both physiological mechanisms resulting from evolution and behavioral mechanisms resulting from conscious cultural adaptations. The physiological control of the body’s core temperature takes place primarily through the hypothalamus, which assumes the role as the body’s “thermostat”. This organ possesses control mechanisms as well as key temperature sensors, which are connected to nerve cells called thermoreceptors. Thermoreceptors come in two subcategories; ones that respond to cold temperatures and ones that respond to warm temperatures. Scattered throughout the body in both peripheral and central nervous systems, these nerve cells are sensitive to changes in temperature and are able to provide useful information to the hypothalamus through the process of negative feedback, thus maintaining a constant core temperature.
There are four avenues of heat loss: convection, conduction, radiation, and evaporation. If skin temperature is greater than that of the surroundings, the body can lose heat by radiation and conduction. In stuffy and hot conditions, the only means by which the body can rid itself of heat is by evaporation. So, when the surrounding temperature is higher than the skin temperature, anything that prevents adequate evaporation will cause the internal body temperature to rise. During intense physical activity (e.g. sports), evaporation becomes the main avenue of heat loss. Humidity affects thermoregulation by limiting sweat evaporation and thus heat loss.
Hypothesis: I think that exercising does affect your pulse rate and will increase the amount pumps (the bumps you feel) because when you exercise your body has to pumps more blood. This is because when you exercise, the cells that are in your muscles need more energy to move. Your muscles get this energy from respiration. This chemical reaction uses up oxygen to release energy from glucose. This travels in the blood so if your muscles need more oxygen and glucose, they get it from the blood. So now we know that when you exercise, your body pumps more blood, which makes your pulse rate faster. Also when you have did a lot of exercise you can feel your pulse rate in your neck beating really fast. I think that my pulse rate will take about four/five/six minutes for it to return back to normal.
Hypothesis. Exercising increases breathing rate and body temperature in humans. Thermoregulation occurs in animals to maintain an internal temperature within a tolerable range.
Discussion:
Based on the result of the experiment, the number of breaths per minute is higher after the exercise than at rest. This is because doing exercises requires energy. The energy is obtained in the form of ATP through cellular respiration. The amount of CO2 production increases which lowers the pH value in the blood. This changes is detected by the chemoreceptor in the aorta and carotid arteries. A signal is sent to the breathing center of the medulla oblongata. An impulse is sent to the heart which increases heart rate. The blood with CO2 is brought faster to the lungs. Besides, an impulse also sent to the breathing musculature which increases breathing rate so that CO2 can be exhaled more rapidly. The body temperature of the student also increases after the exercise. This is because the by-product respiration is carbon dioxide, water and heat. During exercise, your body produced more heat than normal because cellular respiration increases. One of the safety measures taken while conducting this experiment is making sure that the individuals with identified health issues do not take part. This is because some health problems can be exacerbated by physical activities. We also had to ensure that the activity does not become competitive to reduce the risk of the activity causing damage. The site for the exercise chosen should also be safe. It should be well-constructed and stable. For example, when using a staircases, they students are instructed to use the handrail and ensure by supervision that this is obeyed. Apart from that, doing low impact exercise as described in this procedure should be safe for most students. Besides, students are required to wear appropriate outfits to avoid tripping or injuries.
During exercise, muscle cells use more oxygen and produce more carbon dioxide. Breathing rate increases so that more oxygen is taken into the lungs and more carbon dioxide is removed from the lungs. Heart rate increases so that more blood travels to the lungs to pick up more oxygen and deliver more carbon dioxide.
Possible sources of error
Miscounting the breathing rate. You shouldn’t define your own breathing rate by simply counting it. This is because as when we are aware of it, our breathing will be more deep and slow. The temperature taken may be inaccurate because it is the surface temperature and not the core temperature. This is because surface temperature is more susceptible to changes in the surrounding. The temperature taken may also be wrong because it is taken before the reading becomes constant, that is after hearing the ‘beep’ sound.
Suggestions on improving the experiment
Ask someone else to count your breathing rate. The person has to sit upright and the number of times the chest rises and falls are counted during one minute. The person also has to breathe normally. To improve the accuracy of the result, the measurement is taken three times to get an average result. Before taking the temperature measurement, dirt or hair should be removed from the forehead.
Validity:
-More trials preformed could help the development of a more clear trend throughout the data
-Everyone using the same amount of weights, and doing the same type of lifting could eliminate the chances of one person working/exercising harder than another
-Using a more accurate tool to measure the amount of time, such as a stopwatch, could improve the validity of the experiment because it would ensure that all of the volunteers are exercising and resting for the same amounts of time.
Conclusion
The hypothesis is accepted. Thermoregulation occurs in animals to maintain the internal temperature at a tolerable range. Exercising also increases the rate of breathing and temperature.
a)
• Elephants:
- skin that is several sizes too big for its body. Heat is lost through the skin so the more skin, the better.
- has wrinkles, higher surface area exposed to the environment, excess heat is lost
- cool down in muddy water: mud collects in their folds and holds moisture near the skin when they leave the pool. The moisture gradually evaporates and cools the body due to mud’s high heat of vaporization
- elephant’s ears: radiate a lot of heat. When it is hot, blood vessels in the ears open and allow blood to cool as it flows within the paper thin skin. They flap their ears to cool the blood. The cool blood travels through the rest of its system, cooling its body and brain
• Penguin:
- they stick together; in brutal winds, they huddle in large groups and take turn standing in the middle, the insulation of others help reduce heat loss by almost half
- feathers are densely packed, overlapping and waterproof. Can control the feathers individually. When the temperature drops, it lifts its feather upright, trapping a layer of insulating air around their body
- feet are small and lined with fat, rocking back on their heel-> minimize the contact of skin expose to ice
- as their blood circulates their body, the absorbs some of the heat before it reaches the feet
b) pH, concentration of CO2
c) Medulla oblongata regulates the rate and depth of breathing in response to ph changes in the cerebrospinal fluid and the pons regulates the tempo.The medulla oblongata is located in the brain stem, anterior to (in front of) the cerebellum.
d) Aorta and carotid artery- chemoreceptor (next to the respiratory center)
Central chemoreceptors of the central nervous system which is located near the brain stem in the medulla oblongata of the base of the brain. Peripheral chemoreceptor which is located in the aortic and carotid arteries. Furthermore, the peripheral is located in the arteries. Lastly, stretch receptors in the wall of bronchi and bronchioles.
1. Central chemoreceptors: These are located on the ventrolateral surface of medulla oblongata and detect changes in the pH of spinal fluid. They can be desensitized over time from chronic hypoxia (oxygen deficiency) and increased carbon dioxide.
2. Peripheral chemoreceptors: These include the aortic body, which detects changes in blood oxygen and carbon dioxide, but not pH, and the carotid body which detects all three. They do not desensitize, and have less of an impact on the respiratory rate compared to the central chemoreceptors.
e) normal CO2 level, physical activity increasesm cellular respiration increases, CO2 production increases, medulla oblongata stimulated, impulse sent, heart rate increasesm( breathing rate increases), blood with CO2 brought faster to the lungs ( CO2 exhaled more quickly)
exercise, high blood CO2 levels, drop in pH, detected by chemoreceptors, medulla stimulates increased rate and depth of breathing, increased rate of removal of CO2 from the body, blood CO2 levels fall, pH of the blood returns to normal
Breathing involves both voluntary and incoluntary actions. During exercise, the level of CO2 increases, the blood becomes more acidic. Chemoreceptors detect the low pH at the medulla obloganta. The carotid and aortic bodies and feeback is fiven to the breathing or respiratory center, The medulla responds by sending more frequent impulses to the intercostal muscle and diaphragm to increse the rate and depth of breathing.
Conclusion:
Another process that could have been used to measure the external and internal effects of exercise on the body could be to also measure the body temperature before and after the exercise is preformed. This could be a good variable to measure because often the amount of perspiration found on a body is a result of the internal and external body temperature. The relationship between the perspiration level and the body temperature is that they are both negative feedback. After exercise, the body tries to return to homeostasis; so when the body temperature increases due to exercise, the body perspires to cool off and return to its regular temperature, which is considered negative feedback.
The body needs energy for all kind of activities. When the body is resting, it needs lower amount of energy. But the more demanding activities we are doing, the more energy is needed. The main source of energy is carbohydrate and fat. The fat and carbohydrates are transformed by the ‘citric acid cycle’ into energy. The chemical energy is transferred to a substance that is called ATP (adenosine triphosphate). The ATP is a small package of energy that is used by the cells. In aerobic respiration oxygen is needed. The waste products are water, carbon dioxide and heat. The oxygen (O2) and carbon dioxide (CO2) is transported to/from the cells by the hemoglobin in the blood from/to the lungs. It is in the lungs, in the border between the capillaries and the alveoli, where the gases are exchanged by diffusion. The heart is the pump which makes the blood circulate in the body. And our breathing enables new air (with O2) to enter the lungs by inhaling and get rid of the old air (with CO2) by exhaling. Therefore with more demanding exercises (eg. running) more energy is needed and therefore also more oxygen is needed (in the citric acid cycle) and more carbon dioxide is produced. Therefore the heart and breathing rate is becoming higher to enable the transportation of carbon dioxide and oxygen.
Normal resting heart rate for an untrained man is 70 - 75 bpm. And it's lower for people that are well trained, it can be low as 25 bpm. And for old people it is higher. Normal breathing rate/min is 13 - 16
With this lab I want to find out how activities affect the heart and breathing rate in humans.
Conclusion:
The aim of this lab was to find out how activities affect the heart and breathing rate in a human. In my lab, I can easily see that the heart and breathing rate become higher during activity.
My data isn't 100% reliable because that measurement that I used wasn’t so good, eg. I measured for 15s and then I multiplied it by 4. If I would make a more accurate lab, I would measure in 60s. Or if even more correct, I could measure for 120s and divide by 2. It would be more accurate if I did like this, because when I measured for 15s and multiplied it by 4, it might be up to 2 heartbeats wrong when I started to measure and up to 2 heartbeats wrong in the end, then I multiply it by 4, so I could get up to 16 heartbeats wrong per minute. But if I measure for 60s, it could be up to 2 wrong in the beginning and up to 2 wrong in the end, which would mean that I would only get up to 4 heartbeats wrong per minute. Eg. if the accurate heartbeat/min is 70, it would be somewhere between 54 bpm and 86 bpm if I measured in 15s, if I measured in 60s it would be somewhere between 66bpm and 74bpm (which is much more reliable).
If I would do the lab even more accurate, I could use a professional pulse and breathing meter and have a treadmill for the testpersons to run on, so the testpersons would make exact the same activity.
In this lab the resting heart rate and the resting breathing rate were much higher than normal. The reason for this was probably that I didn’t measured the real resting rate for pulse and breathing. The persons was probably not relaxed. So in next lab I would make sure that the persons are relaxing.
It would be interesting to measure the heart and breathing rate on a smoker or a person that has certain health problems as eg. asthma, or a person that lives in a place where the environment is polluted, and how they respond to exercise, and compare to my results.In these persons, the gas exchange is slower, and smoking also has that negative effect that the hemoglobin can bind less oxygen because of it is occupied of carbon monoxide (CO). So if I would make a new study with persons in this group, I would probably get the results that their heart will beat faster and they will have much harder to make exercices.
According to the literature obesity, alcohol and drugs can affect a person’s heart and breathing rate. For example alcohol depresses both heart and breathing rate, which makes it harder to make exercices. Some drugs (medicines) can change the heart rate or make it easier to breath, eg. asthma drugs (eg. ventolin) make the muscles around the bronchi relax so that the tubes open and it is easier to breathe. Other drugs as nitroglycerine is used in angina pectoris and it makes the arteries around the heart becoming broader and let more blood pass to the heart and lower the heart rate.
When we don’t use the energy sources (fat, carbohydrates and proteins) that we eat, they get stored as glycogen and fat. If there is too big excess of energy sources, one become fat. Fat people have more mass and weighs more than not fat people, so they also need more energy and oxygen to do activities. Too much fat in the diet stops muscle cells to take up glucose from the blood and makes the cells to slow down the release of needed energy.
Discussion:
During exercise the body exhales more carbon dioxide than it would when it is at the state of rest. Exhaling more carbon dioxide is a result of the body taking in more oxygen, which results in the body taking in more breaths and the heartbeat to rise. In the results, all of the students exhaled more oxygen after exercising than they did while at rest. This is proven by the solution changing color when a certain amount of carbon dioxide was blown into it. The color change proves the students exhaled more while exercising. While the students were exercising, the body began to use up energy and look for a source to supply that energy. By breathing in more oxygen, the body is getting more oxygen to its cells, which lowers the heart rate and improves circulation for more energy. When one exercises, their body needs more energy. In order to obtain this energy, the body's breathing rate goes up, thus causing the body to exhale more carbon dioxide. This energy that the body gets from breathing in more air is used by the body’s muscles. Once the muscles are supplied with oxygen, it allows the body to break down stored up glucose. This is how the body supplies itself with enough energy to keep contracting.
Conclusion:
In this lab, students learn about carbon dioxide production levels as a result from different heart and breathing rates, which are altered by exercise. As the body exercises, the body must pump more blood, which carries oxygen, to the muscles. During exercise, a cellular respiration takes place in the muscles and carbon dioxide is the product, raising the levels of carbon dioxide in the body. The carbon dioxide is released from the body through exhaled air, thus there is more of it after a person exercises. Understanding why carbon dioxide levels rise and being able to test them is important to understanding biological processes.
Referencing
Boundless n.d, ‘Respiratory system’, viewed on 20th May 2017, https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/respiratory-system-22/respiration-control-212/chemoreceptor-regulation-of-breathing-1039-6384/
CYR, B 2014, ‘What effect does exercise have on your body temperature?’, viewed on 23rd May 2017, http://www.livestrong.com/article/380666-what-effect-does-exercise-have-on-your-body-temperature/
John Hopkins University n.d., http://www.hopkinsmedicine.org/healthlibrary/conditions/cardiovascular_diseases/vital_signs_body_temperature_pulse_rate_respiration_rate_blood_pressure_85,P00866/
Kutti, A n.d., ‘Respiration lab - Heart and breathing rate during activity’, viewed on 21st May 2017,
http://www.science123.n.nu/respiration
Mdco n.d., ‘Thermometer’, viewed on 22nd May 2017, http://www.mdco.gov.hk/english/emp/emp_gp/files/thermometer_eng.pdf
Nullfield Foundation 2011, ‘Observing the effects of exercise on the human body’, viewed on 22nd May 2017, http://www.nuffieldfoundation.org/practical-biology/observing-effects-exercise-human-body
Normal breathing n.d.http://www.normalbreathing.com/index-rate.php
Williams, G (2000), Advanced biology for you (p.311-313), (1st edition), England: Stanley Thornes Ltd
Living organisms exist in habitats where the temperature ranges from 115 C in volcanic vents to -40 C at the poles. An organism’s temperature varies according to the amount of heat it gains and the amount of heat it loses. If heat gain is greater than heat loss, the temperature of the organism will rise and vice versa. To maintain a stable body temperature, an organism needs to balance its heat gain with its heat loss. Thermoregulation is the process by which animals maintain an internal temperature within a tolerable range. It contributes to homeostasis and involves anatomy, physiology and behavior. The experiment is conducted to study the effects of exercise on the breathing rate and body temperature of a human. It can be done by measuring the number of breathing rate during resting state an after a workout. Breathing rate is also known as respiration rate. It is measured by counting the number of breathes for one minute by counting the number of times the chest rises. For adults, the normal breathing rate is 12-18 breaths per minute. People who are ill, such as those with lung or heart disease, may have a change in breathing rate. Other factors that may affect breathing rates are carbon dioxide and concentration which causes a change in pH value of the blood. Carbon dioxide concentration may increase during exercises which use a lot of energy. The rate of respiration increases to provide more energy for the body to do work. This results in an increase in CO2 level as glucose is broken down into ATP and CO2. Drugs and alcohol such as narcotic pain reliever and sedative may depress the activity of the respiratory system. On the other hand, the temperature of the student is also measured before and after the workout using a thermometer.
Most body heat is generated in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles. Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the human body, placing it in great danger of injury or even death. For humans, adaptation to varying climatic conditions includes both physiological mechanisms resulting from evolution and behavioral mechanisms resulting from conscious cultural adaptations. The physiological control of the body’s core temperature takes place primarily through the hypothalamus, which assumes the role as the body’s “thermostat”. This organ possesses control mechanisms as well as key temperature sensors, which are connected to nerve cells called thermoreceptors. Thermoreceptors come in two subcategories; ones that respond to cold temperatures and ones that respond to warm temperatures. Scattered throughout the body in both peripheral and central nervous systems, these nerve cells are sensitive to changes in temperature and are able to provide useful information to the hypothalamus through the process of negative feedback, thus maintaining a constant core temperature.
There are four avenues of heat loss: convection, conduction, radiation, and evaporation. If skin temperature is greater than that of the surroundings, the body can lose heat by radiation and conduction. In stuffy and hot conditions, the only means by which the body can rid itself of heat is by evaporation. So, when the surrounding temperature is higher than the skin temperature, anything that prevents adequate evaporation will cause the internal body temperature to rise. During intense physical activity (e.g. sports), evaporation becomes the main avenue of heat loss. Humidity affects thermoregulation by limiting sweat evaporation and thus heat loss.
Hypothesis: I think that exercising does affect your pulse rate and will increase the amount pumps (the bumps you feel) because when you exercise your body has to pumps more blood. This is because when you exercise, the cells that are in your muscles need more energy to move. Your muscles get this energy from respiration. This chemical reaction uses up oxygen to release energy from glucose. This travels in the blood so if your muscles need more oxygen and glucose, they get it from the blood. So now we know that when you exercise, your body pumps more blood, which makes your pulse rate faster. Also when you have did a lot of exercise you can feel your pulse rate in your neck beating really fast. I think that my pulse rate will take about four/five/six minutes for it to return back to normal.
Hypothesis. Exercising increases breathing rate and body temperature in humans. Thermoregulation occurs in animals to maintain an internal temperature within a tolerable range.
Discussion:
Based on the result of the experiment, the number of breaths per minute is higher after the exercise than at rest. This is because doing exercises requires energy. The energy is obtained in the form of ATP through cellular respiration. The amount of CO2 production increases which lowers the pH value in the blood. This changes is detected by the chemoreceptor in the aorta and carotid arteries. A signal is sent to the breathing center of the medulla oblongata. An impulse is sent to the heart which increases heart rate. The blood with CO2 is brought faster to the lungs. Besides, an impulse also sent to the breathing musculature which increases breathing rate so that CO2 can be exhaled more rapidly. The body temperature of the student also increases after the exercise. This is because the by-product respiration is carbon dioxide, water and heat. During exercise, your body produced more heat than normal because cellular respiration increases. One of the safety measures taken while conducting this experiment is making sure that the individuals with identified health issues do not take part. This is because some health problems can be exacerbated by physical activities. We also had to ensure that the activity does not become competitive to reduce the risk of the activity causing damage. The site for the exercise chosen should also be safe. It should be well-constructed and stable. For example, when using a staircases, they students are instructed to use the handrail and ensure by supervision that this is obeyed. Apart from that, doing low impact exercise as described in this procedure should be safe for most students. Besides, students are required to wear appropriate outfits to avoid tripping or injuries.
During exercise, muscle cells use more oxygen and produce more carbon dioxide. Breathing rate increases so that more oxygen is taken into the lungs and more carbon dioxide is removed from the lungs. Heart rate increases so that more blood travels to the lungs to pick up more oxygen and deliver more carbon dioxide.
Possible sources of error
Miscounting the breathing rate. You shouldn’t define your own breathing rate by simply counting it. This is because as when we are aware of it, our breathing will be more deep and slow. The temperature taken may be inaccurate because it is the surface temperature and not the core temperature. This is because surface temperature is more susceptible to changes in the surrounding. The temperature taken may also be wrong because it is taken before the reading becomes constant, that is after hearing the ‘beep’ sound.
Suggestions on improving the experiment
Ask someone else to count your breathing rate. The person has to sit upright and the number of times the chest rises and falls are counted during one minute. The person also has to breathe normally. To improve the accuracy of the result, the measurement is taken three times to get an average result. Before taking the temperature measurement, dirt or hair should be removed from the forehead.
Validity:
-More trials preformed could help the development of a more clear trend throughout the data
-Everyone using the same amount of weights, and doing the same type of lifting could eliminate the chances of one person working/exercising harder than another
-Using a more accurate tool to measure the amount of time, such as a stopwatch, could improve the validity of the experiment because it would ensure that all of the volunteers are exercising and resting for the same amounts of time.
Conclusion
The hypothesis is accepted. Thermoregulation occurs in animals to maintain the internal temperature at a tolerable range. Exercising also increases the rate of breathing and temperature.
a)
• Elephants:
- skin that is several sizes too big for its body. Heat is lost through the skin so the more skin, the better.
- has wrinkles, higher surface area exposed to the environment, excess heat is lost
- cool down in muddy water: mud collects in their folds and holds moisture near the skin when they leave the pool. The moisture gradually evaporates and cools the body due to mud’s high heat of vaporization
- elephant’s ears: radiate a lot of heat. When it is hot, blood vessels in the ears open and allow blood to cool as it flows within the paper thin skin. They flap their ears to cool the blood. The cool blood travels through the rest of its system, cooling its body and brain
• Penguin:
- they stick together; in brutal winds, they huddle in large groups and take turn standing in the middle, the insulation of others help reduce heat loss by almost half
- feathers are densely packed, overlapping and waterproof. Can control the feathers individually. When the temperature drops, it lifts its feather upright, trapping a layer of insulating air around their body
- feet are small and lined with fat, rocking back on their heel-> minimize the contact of skin expose to ice
- as their blood circulates their body, the absorbs some of the heat before it reaches the feet
b) pH, concentration of CO2
c) Medulla oblongata regulates the rate and depth of breathing in response to ph changes in the cerebrospinal fluid and the pons regulates the tempo.The medulla oblongata is located in the brain stem, anterior to (in front of) the cerebellum.
d) Aorta and carotid artery- chemoreceptor (next to the respiratory center)
Central chemoreceptors of the central nervous system which is located near the brain stem in the medulla oblongata of the base of the brain. Peripheral chemoreceptor which is located in the aortic and carotid arteries. Furthermore, the peripheral is located in the arteries. Lastly, stretch receptors in the wall of bronchi and bronchioles.
1. Central chemoreceptors: These are located on the ventrolateral surface of medulla oblongata and detect changes in the pH of spinal fluid. They can be desensitized over time from chronic hypoxia (oxygen deficiency) and increased carbon dioxide.
2. Peripheral chemoreceptors: These include the aortic body, which detects changes in blood oxygen and carbon dioxide, but not pH, and the carotid body which detects all three. They do not desensitize, and have less of an impact on the respiratory rate compared to the central chemoreceptors.
e) normal CO2 level, physical activity increasesm cellular respiration increases, CO2 production increases, medulla oblongata stimulated, impulse sent, heart rate increasesm( breathing rate increases), blood with CO2 brought faster to the lungs ( CO2 exhaled more quickly)
exercise, high blood CO2 levels, drop in pH, detected by chemoreceptors, medulla stimulates increased rate and depth of breathing, increased rate of removal of CO2 from the body, blood CO2 levels fall, pH of the blood returns to normal
Breathing involves both voluntary and incoluntary actions. During exercise, the level of CO2 increases, the blood becomes more acidic. Chemoreceptors detect the low pH at the medulla obloganta. The carotid and aortic bodies and feeback is fiven to the breathing or respiratory center, The medulla responds by sending more frequent impulses to the intercostal muscle and diaphragm to increse the rate and depth of breathing.
Conclusion:
Another process that could have been used to measure the external and internal effects of exercise on the body could be to also measure the body temperature before and after the exercise is preformed. This could be a good variable to measure because often the amount of perspiration found on a body is a result of the internal and external body temperature. The relationship between the perspiration level and the body temperature is that they are both negative feedback. After exercise, the body tries to return to homeostasis; so when the body temperature increases due to exercise, the body perspires to cool off and return to its regular temperature, which is considered negative feedback.
The body needs energy for all kind of activities. When the body is resting, it needs lower amount of energy. But the more demanding activities we are doing, the more energy is needed. The main source of energy is carbohydrate and fat. The fat and carbohydrates are transformed by the ‘citric acid cycle’ into energy. The chemical energy is transferred to a substance that is called ATP (adenosine triphosphate). The ATP is a small package of energy that is used by the cells. In aerobic respiration oxygen is needed. The waste products are water, carbon dioxide and heat. The oxygen (O2) and carbon dioxide (CO2) is transported to/from the cells by the hemoglobin in the blood from/to the lungs. It is in the lungs, in the border between the capillaries and the alveoli, where the gases are exchanged by diffusion. The heart is the pump which makes the blood circulate in the body. And our breathing enables new air (with O2) to enter the lungs by inhaling and get rid of the old air (with CO2) by exhaling. Therefore with more demanding exercises (eg. running) more energy is needed and therefore also more oxygen is needed (in the citric acid cycle) and more carbon dioxide is produced. Therefore the heart and breathing rate is becoming higher to enable the transportation of carbon dioxide and oxygen.
Normal resting heart rate for an untrained man is 70 - 75 bpm. And it's lower for people that are well trained, it can be low as 25 bpm. And for old people it is higher. Normal breathing rate/min is 13 - 16
With this lab I want to find out how activities affect the heart and breathing rate in humans.
Conclusion:
The aim of this lab was to find out how activities affect the heart and breathing rate in a human. In my lab, I can easily see that the heart and breathing rate become higher during activity.
My data isn't 100% reliable because that measurement that I used wasn’t so good, eg. I measured for 15s and then I multiplied it by 4. If I would make a more accurate lab, I would measure in 60s. Or if even more correct, I could measure for 120s and divide by 2. It would be more accurate if I did like this, because when I measured for 15s and multiplied it by 4, it might be up to 2 heartbeats wrong when I started to measure and up to 2 heartbeats wrong in the end, then I multiply it by 4, so I could get up to 16 heartbeats wrong per minute. But if I measure for 60s, it could be up to 2 wrong in the beginning and up to 2 wrong in the end, which would mean that I would only get up to 4 heartbeats wrong per minute. Eg. if the accurate heartbeat/min is 70, it would be somewhere between 54 bpm and 86 bpm if I measured in 15s, if I measured in 60s it would be somewhere between 66bpm and 74bpm (which is much more reliable).
If I would do the lab even more accurate, I could use a professional pulse and breathing meter and have a treadmill for the testpersons to run on, so the testpersons would make exact the same activity.
In this lab the resting heart rate and the resting breathing rate were much higher than normal. The reason for this was probably that I didn’t measured the real resting rate for pulse and breathing. The persons was probably not relaxed. So in next lab I would make sure that the persons are relaxing.
It would be interesting to measure the heart and breathing rate on a smoker or a person that has certain health problems as eg. asthma, or a person that lives in a place where the environment is polluted, and how they respond to exercise, and compare to my results.In these persons, the gas exchange is slower, and smoking also has that negative effect that the hemoglobin can bind less oxygen because of it is occupied of carbon monoxide (CO). So if I would make a new study with persons in this group, I would probably get the results that their heart will beat faster and they will have much harder to make exercices.
According to the literature obesity, alcohol and drugs can affect a person’s heart and breathing rate. For example alcohol depresses both heart and breathing rate, which makes it harder to make exercices. Some drugs (medicines) can change the heart rate or make it easier to breath, eg. asthma drugs (eg. ventolin) make the muscles around the bronchi relax so that the tubes open and it is easier to breathe. Other drugs as nitroglycerine is used in angina pectoris and it makes the arteries around the heart becoming broader and let more blood pass to the heart and lower the heart rate.
When we don’t use the energy sources (fat, carbohydrates and proteins) that we eat, they get stored as glycogen and fat. If there is too big excess of energy sources, one become fat. Fat people have more mass and weighs more than not fat people, so they also need more energy and oxygen to do activities. Too much fat in the diet stops muscle cells to take up glucose from the blood and makes the cells to slow down the release of needed energy.
Discussion:
During exercise the body exhales more carbon dioxide than it would when it is at the state of rest. Exhaling more carbon dioxide is a result of the body taking in more oxygen, which results in the body taking in more breaths and the heartbeat to rise. In the results, all of the students exhaled more oxygen after exercising than they did while at rest. This is proven by the solution changing color when a certain amount of carbon dioxide was blown into it. The color change proves the students exhaled more while exercising. While the students were exercising, the body began to use up energy and look for a source to supply that energy. By breathing in more oxygen, the body is getting more oxygen to its cells, which lowers the heart rate and improves circulation for more energy. When one exercises, their body needs more energy. In order to obtain this energy, the body's breathing rate goes up, thus causing the body to exhale more carbon dioxide. This energy that the body gets from breathing in more air is used by the body’s muscles. Once the muscles are supplied with oxygen, it allows the body to break down stored up glucose. This is how the body supplies itself with enough energy to keep contracting.
Conclusion:
In this lab, students learn about carbon dioxide production levels as a result from different heart and breathing rates, which are altered by exercise. As the body exercises, the body must pump more blood, which carries oxygen, to the muscles. During exercise, a cellular respiration takes place in the muscles and carbon dioxide is the product, raising the levels of carbon dioxide in the body. The carbon dioxide is released from the body through exhaled air, thus there is more of it after a person exercises. Understanding why carbon dioxide levels rise and being able to test them is important to understanding biological processes.
Referencing
Boundless n.d, ‘Respiratory system’, viewed on 20th May 2017, https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/respiratory-system-22/respiration-control-212/chemoreceptor-regulation-of-breathing-1039-6384/
CYR, B 2014, ‘What effect does exercise have on your body temperature?’, viewed on 23rd May 2017, http://www.livestrong.com/article/380666-what-effect-does-exercise-have-on-your-body-temperature/
John Hopkins University n.d., http://www.hopkinsmedicine.org/healthlibrary/conditions/cardiovascular_diseases/vital_signs_body_temperature_pulse_rate_respiration_rate_blood_pressure_85,P00866/
Kutti, A n.d., ‘Respiration lab - Heart and breathing rate during activity’, viewed on 21st May 2017,
http://www.science123.n.nu/respiration
Mdco n.d., ‘Thermometer’, viewed on 22nd May 2017, http://www.mdco.gov.hk/english/emp/emp_gp/files/thermometer_eng.pdf
Nullfield Foundation 2011, ‘Observing the effects of exercise on the human body’, viewed on 22nd May 2017, http://www.nuffieldfoundation.org/practical-biology/observing-effects-exercise-human-body
Normal breathing n.d.http://www.normalbreathing.com/index-rate.php
Williams, G (2000), Advanced biology for you (p.311-313), (1st edition), England: Stanley Thornes Ltd
Lab Report: The effect of pH and temperature on enzyme activity
Introduction:
Enzymes are proteins that speed up many chemical reactions in cells. They act on substrates. Each enzyme acts only on specific substrates. Also it might be a reaction between a specific combination of substrates and a specific enzyme. Enzymes affect the rate of almost all chemical reactions which take place in organisms. Like all other proteins, enzyme function may be affected by a change in any aspect of its structure. The effect of a change in enzyme structure is called denaturation. Some substrates fit in the active site of the enzymes, but they are not taken apart by enzymes.They don’t let enzyme, which they occupied, take part in reactions anymore. They are called inhibitors.
The activity of enzymes is affected by pH, by temperature, presence of inhibitors, enzyme concentration and substrate concentration. There are still large areas of medical research in which the diagnostic potential of enzyme reactions has not been explored at all.
Catalase is an enzyme which is produced by every cell to break down hydrogen peroxide. Catalase is located in a cell organelle called the peroxisome. Hydrogen peroxide is a waste product of cellular activity that is poisonous to cells. However, it was used for a long time as a wound treatment (Some Eastern European countries still use it). Catalase speeds up the decomposition of hydrogen peroxide into harmless water and oxygen gas.
Dependent variable: Catalase enzyme activity (measured as % of oxygen produced)
Independent variable 1 experiment: pH 2 experiment: temperature
Controlled variable Amount of time
The purpose of this lab was to determine the effect of pH and temperature on the rate of catalase enzyme activity. Since the catalase speeds up the decomposition of hydrogen, the rate of catalase activity was measured indirectly by measuring the change in % oxygen produced over a fixed time period.
There were two experiments perfomed. First one determined the dependence of rate of catalase activity on the level of pH. In the first experiment our hypothesis was that if the level of pH decreases, then the rate of hydrogen peroxide degradation decreases. The second experiment investigated the effect of temperature on catalase activity. In the second experiment our hypothesis was that if the temperature decreases, then the speed of hydrogen peroxide decomposition decreases.
Materials and Methods:
Since hydrogen peroxide is potentially damaging to skin and eyes, goggles were worn for the duration of the experiment.
A Vernier® Oxygen Gas Sensor probe was connected to a Vernier Logger Pro® data collector, the apparatus was checked to confirm that it was working correctly.
200 ml of catalase solution was prepared by mixing 25 g of COOP™ yeast into lukewarm distilled water.
Experiment 1: Effect of pH on the rate of decomposition of hydrogen peroxide:
The first experiment investigated the effect of pH change on the rate of decomposition of hydrogen peroxide.
(Using a 2 ml measuring pipette), 5 ml of 3% hydrogen peroxide (H2O2) were measured into 3 25 ml test tubes (labelled pH4, pH7 and pH10).
5 ml of specific pH buffer (pH 4, pH 7 and pH 10) were added to each test tube.
The pH of the buffer/ H2O2 mixture was measured using universal pH indicator.
2 ml of catalase was added to the test tube labelled pH 4, the mixture was transferred into a closed chamber and a stopwatch was started. 30 s after transfer, measurement of % oxygen was started using the Vernier® apparatus. Data collection was continued for 180 s. This procedure was repeated for the test tubes containing hydrogen peroxide/pH 7 and pH 10 buffer. Data was saved and transferred to EXCEL for the purpose of data analysis.
Experiment 2: Effect of temperature on the rate of decomposition of hydrogen peroxide:
The second experiment investigated the effect of temperature change on the rate of decomposition of hydrogen peroxide.
An ice bath was prepared and maintained at 0 oC. 3% hydrogen peroxide, catalase solution and distilled water were maintained in the ice bath. Temperature was confirmed using a thermometer.
Similarly, a hot water bath was prepared and maintained at 60 oC. 3% hydrogen peroxide, catalase solution and distilled water were maintained in the hot water bath. Temperature was confirmed using a thermometer.
(Using a 2 ml measuring pipette), 5 ml of 3% hydrogen peroxide (H2O2) were measured into 3 X 25 ml test tubes (labelled 0 oC, 22 oC and 60 oC).
5 ml of distilled water were added to each test tube.
2 ml of catalase was added to the test tube labelled 0 oC, the mixture was transferred into a closed chamber and a stopwatch was started. 30 s after transfer, measurement of % oxygen was started using the Vernier® apparatus. Data collection was continued for 180 s. This procedure was repeated for the test tubes containing hydrogen peroxide/22 oC and 60 oC. Data was saved and transferred to EXCEL for the purpose of data analysis.
Discussion:
In Experiment 1 it was observed that any change in the level of pH (both decrease and increase) affected the speed of breakdown of hydrogen peroxide. In Experiment 1 was observed that both decrease and increase of the level of pH increased the speed of hydrogen peroxide breakdown. However, the rate of oxygen production was higher at the pH level 10 than at the pH level 4. Without any catalase or hydrogen peroxide,no oxygen was produced, since there was no t hydrogen peroxide breakdown. Our hypothesis was refuted. We assumed that the higher the pH, the faster the rate of hydrogen peroxide breakdown. However, the patterns which were assumed were not obeserved in the experiment. After the experiment was made a conclusion that any change in pH speeds up the produce of oxygen by breakdwon of hydrogen peroxide, but the increase in pH speeds up the breakdown process higher, rather than decrease.
In Experiment 2 it was observed that any change in temperature negatively affects the speed of hydrogen peroside breakdown Not exactly – a change in temperature affects the rate of hydrogen peroxide breakdown. The rate of decomposition of hydrogen peroxide at room temperature was much greater than at 60 Co and 0 Co. It was assumed before the experiment that the lower the temperature, the lower speed of hydrogen peroxide decomposition. Our hypothesis was partly upheld by experimental data.. However, it was observed that any great change in temperature negatively affects enzyme catalase activity, since at these temperatures enzyme denatures.
Error sources:
In both experiments, more precise and accurate apparatus should be used to measure the volume of liquids (pH solutions, yeast, hydrogen peroxide), to control the ratio of liquids and the purity of the. The measuring burette would perfectly fit.
The oxygen measuring apparatus also should be improved,. The devices were not calibrated before the experiment began, andtheir accuracy was not confirmed. Also it was unknown whether these devices were calibrated. These factors could affect the data that was collected.
In Experiment 2 to control the temperature of catalase and hydrogen peroxide apart from water and ice bath, the temperature of the environment (room where exepriment was performed) should also be controlled, as the catalase and hydrogen peroxide, in order to improve the relaibility of the results obtained.
Also in each, there was a 30 second delay before oxygen measurement began. . As human error factor s are present in every experiment, there might be a mistake of 1-2 seconds, which may have affected the results of the experiment.
Conclusion:
In experiment, 1 was observed that a change in pH alters the rate of decomposition of hydrogen peroxide. The optimal pH for cyeast catalase activity appears to be pH 10. It ust be recognized, howebver, that at extreme pH levels (pH 1-2 and pH 13-14 ), the enzyme denatures and the speed of hydrogen peroxide breakdown decreases. In experiment 2, extremes of temperature reduced the rate of hydrogen peroxide breakdown. It happened, because at these temperatures hydrogen peroxide denatures. In fact, at low temperatures the enzyme should not be denatured, but the reaction rate would be slow since the rate of enzyme-substrate collisions would be slow.
This is a different font to the rest of the document.
References:
• 27 July 2004, SEPS. Catalase FAQ.
• Repose, D. 2008. Introductory Biology at UNCG. Writing a lab report.
• 2009, MHS Science. Sample Lab Report: Factors which Affect the Acivity of the Enzyme Catalase
Tuesday, February 13, 2018
SPM 2017 Answers
Sejarah
1. C 11. C 21. B 31. D
2. D 12. A 22. D 32. D
3. B 13. C 23. B 33. D
4. C 14. B 24. A 34. C
5. A 15. C 25. D 35. A
6. C 16. A 26. D 36. D
7. C 17. B 27. A 37. B
8. B 18. A 28. B 38. A
9. A 19. A 29. D 39. B
10. C 20. C 30. C 40. D
Mathematics
1. D 11. A 21. B 31. B
2. C 12. C 22. C 32. C
3. D 13. B 23. B 33. B
4. A 14. A 24. C 34. A
5. B 15. D 25. A 35. C
6. B 16. B 26. B 36. B
7. D 17. D 27. B 37. D
8. D 18. C 28. C 38. C
9. D 19. A 29. D 39. B
10. A 20. A 30. B 40. C
Chemistry
| 1. C | 11. C | 21. D | 31. C | 41.C |
| 2. C | 12. C | 22. B | 32. A | 42. C |
| 3. D | 13. D | 23. D | 33. C | 43. B |
| 4. A | 14. A | 24. A | 34. B | 44. B |
| 5. D | 15. D | 25. A | 35. C | 45. C |
| 6. C | 16. B | 26. D | 36. B | 46. C |
| 7. B | 17. D | 27. A | 37. B | 47. A |
| 8. D | 18. A | 28. A | 38. B | 48. A |
| 9. B | 19. C | 29. B | 39. D | 49. B |
| 10.A | 20. D | 30. B | 40. A | 50.D |
Physics
| 1. D | 11. A | 21. C | 31. C | 41.A |
| 2. B | 12. C | 22. B | 32. B | 42. D |
| 3. B | 13. C | 23. C | 33. A | 43. D |
| 4. C | 14. A | 24. B | 34. B | 44. A |
| 5. B | 15. A | 25. B | 35. B | 45. B |
| 6. A | 16. A | 26. D | 36. B | 46. A |
| 7. B | 17. A | 27. D | 37. C | 47. B |
| 8. D | 18. C | 28. D | 38. D | 48. D |
| 9. C | 19. C | 29. A | 39. A | 49. B |
| 10.D | 20. C | 30. B | 40. D | 50. A |
Biology
| 1. B | 11. A | 21. D | 31. C | 41.D |
| 2. D | 12. C | 22. C | 32. A | 42. C |
| 3. B | 13. C | 23. B | 33. D | 43. A |
| 4. B | 14. B | 24. A | 34. C | 44. D |
| 5. C | 15. D | 25. C | 35. C | 45. C |
| 6. A | 16. B | 26. B | 36. D | 46. A |
| 7. C | 17. D | 27. D | 37. D | 47. A |
| 8. A | 18. A | 28. C | 38. B | 48. C |
| 9. B | 19. C | 29. B | 39. B | 49. B |
| 10. C | 20. A | 30. C | 40. B | 50. B |
Wednesday, February 7, 2018
Original Mille Crepe Cake Recipe
Making a crepe cake takes a lot of time and patience.
Ingredients:
For the crêpe batter:
6 tablespoons butter
3 cups milk
6 eggs
1 ½ cups flour
5 1/2 tablespoons sugar
A pinch salt
For the vanilla pastry cream:
2 cups milk
1 vanilla bean, halved and scraped
6 egg yolks
½ cup sugar
1/3 cup cornstarch, sifted
3 ½ tablespoons butter
For the assembly:
Vegetable oil
2 cups heavy cream
2 tablespoon sugar or more
METHOD:
The day before, make the crepe batter and the pastry cream.
Batter:
• In a small pan, cook the butter until brown like hazelnuts. Set aside.
• In another small pan, heat the milk until steaming; allow to cool for 10 minutes.
• In a mixer on medium-low speed, beat together the eggs, flour, sugar and salt.
• Slowly add the hot milk and browned butter.
• Pour into a container with a spout, cover and refrigerate for at least 2 hours.
Pastry cream:
• Bring the milk with the vanilla bean (and scrapings) to a boil, then set aside for 10 minutes; remove bean.
• Fill a large bowl with ice and set aside a small bowl that can hold the finished pastry cream and be placed in this ice bath.
• In a medium heavy-bottomed pan, whisk together the egg yolks, sugar and cornstarch.
• Gradually whisk in the hot milk, then place pan over high heat and bring to a boil, whisking vigorously for 1 to 2 minutes.
• Press the pastry cream through a fine-meshed sieve into the small bowl.
• Set the bowl in the ice bath and stir until the temperature reaches 140 degrees on an instant-read thermometer.
• Stir in the butter.
• When completely cool, cover and refrigerate.
Assemble the cake the next day:
• Bring the batter to room temperature.
• Place a nonstick or seasoned 9-inch crepe pan over medium heat. Swab the surface with the oil, then add about 3 tablespoons batter and swirl to cover the surface.
• Cook until the bottom just begins to brown, about 1 minute, then carefully lift an edge and flip the crepe with your fingers.
• Cook on the other side for no longer than 5 seconds.
• Repeat until you have 20 perfect crepes.
• Whip the heavy cream with the tablespoon sugar and the Kirsch. Then, fold it into the pastry cream
• Lay 1 crepe on a cake plate.
• Using an icing spatula, completely cover with a thin layer of pastry cream (about 1/4 cup).
• Cover with a crepe and repeat to make a stack of 20, with the best-looking crepe on top.
• Chill for at least 2 hours.
• Set out for 30 minutes before serving.
• If you have a blowtorch for crème brûlée sprinkle the top crepe with 2 tablespoons sugar and caramelize with the torch; otherwise, dust with confectioners’ sugar.
• Slice like a cake.
Ingredients:
For the crêpe batter:
6 tablespoons butter
3 cups milk
6 eggs
1 ½ cups flour
5 1/2 tablespoons sugar
A pinch salt
For the vanilla pastry cream:
2 cups milk
1 vanilla bean, halved and scraped
6 egg yolks
½ cup sugar
1/3 cup cornstarch, sifted
3 ½ tablespoons butter
For the assembly:
Vegetable oil
2 cups heavy cream
2 tablespoon sugar or more
METHOD:
The day before, make the crepe batter and the pastry cream.
Batter:
• In a small pan, cook the butter until brown like hazelnuts. Set aside.
• In another small pan, heat the milk until steaming; allow to cool for 10 minutes.
• In a mixer on medium-low speed, beat together the eggs, flour, sugar and salt.
• Slowly add the hot milk and browned butter.
• Pour into a container with a spout, cover and refrigerate for at least 2 hours.
Pastry cream:
• Bring the milk with the vanilla bean (and scrapings) to a boil, then set aside for 10 minutes; remove bean.
• Fill a large bowl with ice and set aside a small bowl that can hold the finished pastry cream and be placed in this ice bath.
• In a medium heavy-bottomed pan, whisk together the egg yolks, sugar and cornstarch.
• Gradually whisk in the hot milk, then place pan over high heat and bring to a boil, whisking vigorously for 1 to 2 minutes.
• Press the pastry cream through a fine-meshed sieve into the small bowl.
• Set the bowl in the ice bath and stir until the temperature reaches 140 degrees on an instant-read thermometer.
• Stir in the butter.
• When completely cool, cover and refrigerate.
Assemble the cake the next day:
• Bring the batter to room temperature.
• Place a nonstick or seasoned 9-inch crepe pan over medium heat. Swab the surface with the oil, then add about 3 tablespoons batter and swirl to cover the surface.
• Cook until the bottom just begins to brown, about 1 minute, then carefully lift an edge and flip the crepe with your fingers.
• Cook on the other side for no longer than 5 seconds.
• Repeat until you have 20 perfect crepes.
• Whip the heavy cream with the tablespoon sugar and the Kirsch. Then, fold it into the pastry cream
• Lay 1 crepe on a cake plate.
• Using an icing spatula, completely cover with a thin layer of pastry cream (about 1/4 cup).
• Cover with a crepe and repeat to make a stack of 20, with the best-looking crepe on top.
• Chill for at least 2 hours.
• Set out for 30 minutes before serving.
• If you have a blowtorch for crème brûlée sprinkle the top crepe with 2 tablespoons sugar and caramelize with the torch; otherwise, dust with confectioners’ sugar.
• Slice like a cake.
Monash University Foundation Year (MUFY)
MUFY is a one year foundation program by Monash University to prepare and familiarize students with the style of teaching and the way students are evaluated in Monash University. It is also easier to enter the university by doing their foundation program as the entree requirement marks are lower compared to other pre-u programs. After finishing your foundation, your application fee to Monash University is waiver. The process to apply is much easier as the administrative handles most of the stuff. They will also inform you the things you have to do. If you are sure you want to enter Monash University, I highly recommend you to do their foundation program. However, even if you have not decided which university to go to, you can still take their program as it is widely accepted in most universities in Malaysia and Australia. However, please check with your desired university whether they do accept the program. Better safe than sorry.
In Malaysia, MUFY is offered in Sunway College Kuala Lumpur and Sunway College Johor Bahru. MUFY is a two semester program (if you don't fail or manage to obtain the results that you want). There are three intakes for the standard program (4 units each semester) which are in January, March and July while only one intake for the intensive program ( 3 units in the first semester and 5 units in the second semester) which is in July. You can choose the subjects that you want either all Science or all Arts or a mixture of both. However, some subjects have prerequisite you have to comply to. English Unit 1 and 2 is compulsory for all students. The subjects offered are:
Another good advantage of being in MUFY is that you can choose your own timetable based on your own preference. The earliest class is at 8.30am and the last class is at 2.45 p.m. Each class is 1 hour and 15 minutes long.
Sunway College offers a variety of scholarship to students not only to those who perform well academically but also those who are good at sports or even music. Click here for more info
Currently, evaluation is based 70% of coursework (small test, lab reports, assignments, presentation, etc) and 30% examination. The structure of the exam change very often so it may not be correct at the time you are reading this article. You will have test nearly every week or group assignments to complete.
In Malaysia, MUFY is offered in Sunway College Kuala Lumpur and Sunway College Johor Bahru. MUFY is a two semester program (if you don't fail or manage to obtain the results that you want). There are three intakes for the standard program (4 units each semester) which are in January, March and July while only one intake for the intensive program ( 3 units in the first semester and 5 units in the second semester) which is in July. You can choose the subjects that you want either all Science or all Arts or a mixture of both. However, some subjects have prerequisite you have to comply to. English Unit 1 and 2 is compulsory for all students. The subjects offered are:
- Fundamental Mathematics - Year 11 Maths. If you are planning to be in the science profession (medicine, pharmacy, engineer, etc) it is better to take the other maths. This subject is more suitable for those entering business school
- Mathematics - Year 12 Maths
- Advanced Mathematics - For those who are maths geeks and those who planned to study engineering. It is not really a prerequisite to enter engineering but it makes it easier for you to cope when you just enter. You have to take Mathematics and Advanced Maths concurrently.
*You cannot take Fundamental Mathematics and Mathematics concurrently.
- Biology
- Chemistry
- Physics
- Information and Computer Technology
- Globalisation
- Accounting
- Economics
Sunway College offers a variety of scholarship to students not only to those who perform well academically but also those who are good at sports or even music. Click here for more info
Currently, evaluation is based 70% of coursework (small test, lab reports, assignments, presentation, etc) and 30% examination. The structure of the exam change very often so it may not be correct at the time you are reading this article. You will have test nearly every week or group assignments to complete.
Tuesday, February 6, 2018
Best Soy-Sauce Flavoured Sauce
Ingredients:
1 C soy sauce1/4 C dark or thick soy sauce
3 C water
1/4 C rice wine (can be replaced with white vineger)
1/4 C sugar
1 cloves of garlic
2 whole star anise
3 large slices of ginger root
1 dried chilli peppers (can add more if you like it to be more spicy)
Method
1. Combine all the ingredients of the sauce and bring the mixture to a boil2. Turn down to simmer and cook sauce for 10 min.
3. Now, the sauce is ready to be used to cook whatever meat or vegetable desired.
I personally prefer to cook the sauce with belly pork meat and hard boiled egg. The sauce should be covered and stored in the refrigerator or freezer after each use. After the sauce has been used several times, remove the layer of fat on the surface and replace with 1/4 cup . The flavour of the sauce improves with time and the sauce can be used over afain for months. As the sauce is used, more soy sauce of the other ingredients may need to be replenished to keep the proper balance of flavours
Form 1 Science Chapter 2
Cell as a Unit of Life
What is a cell?
- a cell is the basic unit of living things which can function on its own
- cells cannot be seen with the naked eye
- a microscope is used to study and observe cells
- Robert Hooke is the first person to study cells on a cork
Structures and Functions of Cells
- they are two types of cells: plant cells and animal cells
- most cells consist of a protoplasm (nucleus and cytoplasm) which is surrounded by a cell membrane
|
Structure
|
Function
|
Characteristics
|
|
Nucleus
|
- controls all cell activities
- contain genes which determine
the inherited characters
|
- dense, spherical structure
- contains chromosomes
|
|
Cytoplasm
|
- the site where chemical
reactions and processes take place
|
- jelly-like substance
- colourless
- contains water and chemical
substances (protein, mineral, stored food)
|
|
Cell membrane
|
- controls all movement in and
out of the cells
|
- semi permeable (allows certain
substances to pass through)
|
|
*Cell wall
|
- maintain the shape of the
cell
- provides mechanical support
and strengthen the cell
|
- contains cellulose
- thick and rigid layer
|
|
*Chloroplast
|
- site where photosynthesis
take place
|
- contain a green pigment
called chlorophyll which is used to absorb sunlight
|
|
*Vacuoles
|
- stored water and minerals,
sugars, proteins and dissolved substances
|
- contains cell sap
|
*only in plant cells
 |
| The image above is taken from BBC |
Comparisons Between Plant Cells and Animal Cells
|
Animal cell
|
Similarities
|
Plant cells
|
|
- have nuclei
- have cytoplasm
- have cell membranes
- are living things
|
||
|
Differences
|
||
|
Irregular
|
Shape
|
Regular
|
|
Does not have vacuoles. If they
do, it is very small
|
Vacuoles
|
Have vacuoles
|
|
Does not have chloroplast
|
Chloroplast
|
Have chloroplast
|
|
Does not have cell wall
|
Cell wall
|
Have cell wall
|
|
Glycogen
|
Food storage
|
Starch
|
|
At the centre
|
Location of nucleus
|
At the edge
|
Unicellular and Multicellular Organisms
Unicellular Organisms
- simple organisms that are made up of one cell
- Animal kingdom: Amoeba and Paramecium
- Plant kingdom: Pleurococcus, Euglena, Chlamydomonas and yeast
- are very tiny and also known as microorganism
Multicellular Organisms
- organisms that have more than one cell
- Animal kingdom: mammals, amphibians, reptiles, birds, fish and Hydra
- Plant kingdom: mosses, algae (Chondrus and Spirogyra), ferns and most of the flowering plants
Senarai Penjodoh Bilangan
|
Penjodoh
Bilangan
|
penggunaannya
|
Contohnya
|
|
angkatan
|
untuk sekumpulan manusia atau benda
|
kapal, tentera, pelukis, penulis
|
|
baris
|
untuk kedudukan benda/manusia yang berbaris
|
orang, kedai, rumah, pokok, tulisan, ayat, meja,
kerusi
|
|
batang
|
untuk menunjukkan benda-benda yang panjang
|
sungai, lilin, galah, tiang, pen, pokok, gigi,
tongkat, kapur, jambatan, jarum
|
|
bentuk
|
untuk benda-benda kecil yang berkeluk
|
mata kail, subang, cincin
|
|
berkas
|
untuk benda-benda yang diikat bersama-sama
|
kunci, lidi, kayu
|
|
bidang
|
untuk benda-benda yang terbentang luas
|
tanah, kain, sawah, permaidani, layar, kebun,
tikar
|
|
biji
|
untuk jenis buah, sayur-sayuran, dan benda-benda
yang kecil
|
labu, lobak, kubis, terung, bola, cawan, guli,
belon, ketupat, batu, telur, gelas
|
|
Bilah
|
untuk benda-benda yang tajam
|
parang, pisau, golok, gunting, sabit, keris
|
|
buah
|
untuk benda-benda besar dan padu, yang tidak
mempunyai bentuk yang tertentu
|
kereta, negeri, rumah, buku, kotak, radio,
bandar, kampung, piano, komputer, kamera
|
|
buku
|
untuk benda-benda yang keadaannya
berketul/berbongkah
|
sabun, roti, benang
|
|
butir
|
untuk benda-benda yang bulat atau kecil
|
telur, batu, manik, beras, peluru
|
|
carik/cebis
|
untuk benda-benda yang dikoyakkan
|
kertas, kain
|
|
cubit
|
untuk benda yang diambil sedikit dengan jari
|
garam, gula, kunyit
|
|
cucuk
|
untuk benda-benda yang dicucuk dengan lidi
|
sate
|
|
das
|
untuk bunyi letupan atau tembakan
|
meriam, pistol, senapang
|
|
deret
|
untuk benda-benda yang tersusun
|
bangunan, rumah, kedai, kereta
|
|
ekor
|
untuk semua jenis binatang
|
nyamuk, semut, kuda, buaya, musang, gajah, arnab,
rama-rama
|
|
genggam
|
untuk benda-benda yang digenggam
|
pasir, beras, padi
|
|
gugus
|
untuk buah-buah ataupun benda
|
anggur, langsat, kelapa sawit, sawit, kunci
|
|
gulung
|
untuk benda-benda yang bergulung
|
filem, permaidani, tikar, dawai, kertas
|
|
helai
|
untuk benda-benda yang nipis dan lebar
|
daun, baju, kertas, kain, tuala, rambut, rumput
|
|
ikat
|
untuk benda-benda yang diikat
|
kayu, lidi, tebu, sayur, papan
|
|
iris
|
untuk benda-benda yang dipotong kecil-kecil
|
bawang, timun, daging, buahbuahan
|
|
jambak
|
untuk benda-benda yang bertangkai atau
berangkai-rangkai
|
bunga, kunci
|
|
kaki
|
untuk benda-benda yang bertangkai
|
payung, cendawan, bungs
|
|
kawan
|
untuk kumpulan haiwan
|
lembu, kambing, lebah, gajah, merpati
|
|
kelompok
|
untuk sekumpulan manusia, haiwan, dan benda
|
burung, awan, pulau, bintang
|
|
kepal
|
untuk benda-benda yang dikepal dengan tangan
|
nasi, pulut, tanah
|
|
keping
|
untuk benda-benda yang nipis atau pipih
|
roti, papan, kad, gambar, biskut, tanah
|
|
kerat
|
untuk bahagian benda-benda yang dipotong
|
roti, tiang
|
|
Ketul
|
untuk benda-benda yang berketul dan padu
|
ais, daging, tulang, sabun, roti
|
|
Kotak
|
untuk benda-benda yang diisikan di dalam kotak
|
mancis, pensel, rokok, sabun, ubat nyamuk
|
|
kuntum
|
untuk bungs
|
mawar, melati, anggerik
|
|
Laras
|
untuk senjata api
|
pistol, senapang, meriam
|
|
lembar
|
benda-benda yang lurus dan panjang
|
kertas, dawai, benang
|
|
longgok
|
untuk benda-benda yang berada dalam longgokan
|
durian, pakaian, tanah, cili
|
|
naskhah
|
untuk bahan bacaan yang berjilid
|
surat khabar, risalah, majalah, makalah, buku
|
|
Orang
|
untuk manusia
|
guru, jururawat, doktor, pekedai, runcit, posmen
|
|
Papan
|
untuk benda-benda yang berbentuk kepingan
|
coklat, petai, mercun
|
|
pasang
|
untuk benda dan manusia yang berpasangan
|
pakaian, kasut, subang, suami isteri, anak
|
|
pangsa
|
untuk bahagian dalam buah
|
durian
|
|
pasukan
|
untuk sekumpulan orang yang berpakaian seragam
|
pemain kompang, polis, tentera pengakap
|
|
patah
|
untuk kata
|
perkataan, kata-kata
|
|
potong
|
untuk benda-benda yang sudah dipotong
|
kuih, daging, roti
|
|
pucuk
|
untuk benda-benda yang halus serta tipis dan
senjata api
|
jarum, surat, pistol, meriam, senapang, rebung
|
|
puntung
|
untuk sebahagian benda yang masih menyala
|
rokok, bara, kayu api
|
|
rangkap
|
untuk puisi
|
pantun, sajak, syair
|
|
rawan
|
untuk benda-benda yang halus, labuh, dan bersirat
|
jala, jaring, pukat
|
|
ruas
|
untuk benda yang beruas-ruas
|
tebu, buluh
|
|
rumpun
|
untuk tumbuhan yang tumbuh rapat-rapat
|
buluh, tebu, serai, pandan, padi
|
|
sikat/sisir
|
untuk buah pisang
|
pisang
|
|
tandan
|
untuk buah-buahan yang bertandan
|
pisang, kelapa, pinang, kelapa sawit
|
|
tangkai
|
untuk buah-buahan, bunga-bungaan, dan daun yang
bertangkai
|
rambutan, duku, kenanga, padi, daun
|
|
titik
|
untuk cecair yang menitis
|
air, darah, dakwat, embun
|
|
tongkol
|
untuk buah yang bertongkol
|
jagung
|
|
ulas
|
untuk isi buah-buahan yang berpangsa
|
durian, limau, nangka, cempedak
|
|
urat
|
untuk benda-benda yang halus dan panjang
|
rambut, benang, dawai,
|
|
utas
|
untuk benda-benda yang panjang
|
tali, dawai, rantai
|
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