Unit 6: Investigative project
Learning aim D: Review the investigative project using correct scientific principles.
Learning aim C: Safely undertake the project, collecting, analysing and presenting the results.
Investigation of the effect of temperature on enzyme activity (Biology)
Consent and confidentiality: none needed
Abstract: To see how temperature effected enzyme activity. Starch was the product to be
broken down by amylase which was the enzyme while using iodine as an indicator of whether
the trial was successful or not. The prediction was that the time taken to break the starch (in
other words see a colour change of iodine) would decrease as the temperature increased from
0°C towards 100°C. It was also stated that the optimum would be around 40°C.
Rational:
The aim was to investigate the effect of temperature on enzymes. The reason this topic was
chosen was because enzymes are involved in almost everything but is mainly thought of
enzymes relating to the digestive system hence, why enzymes were decided. The intention was
to find out the optimum temperature on an enzyme and why the optimum was that specific
temperature. A theory that was to be investigated was that the optimum temperature was 37°C
for the specific enzymes chosen (amylase and starch). The objective was to obtain results that
closely mirror similar human environments the enzymes operate in.
Investigation: The effect of temperature on enzyme activity
Aim: To see the effect of temperature on amylase against starch.
Independent variable (the variable that was changed): Temperature
Dependant variable (the variable that was being measured): Time it takes for iodine to change
colour
Control variable (the variable that was kept the same throughout the experiment): Enzyme
solutions
Extraneous variable: Inconsistent temperatures of the solutions
Hypothesis: As the temperature changes, the enzyme activity changes but in accordance with
what the best temperature e.g., 40°C amylase worked at to break down starch at the pH of 7.
,Prediction: The best temperature for the experiment was to undergo at around 40°C because
it's close to 37°C which is the normal body temperature. The reason for 37°C is because it's the
natural body temperature due to homeostasis and evolution, the enzymes in human bodies
adapted to thrive in that environment.
Null hypothesis: The temperature does not catalase the amylase.
Potential limitations of the experiment: After 40°C the results may seem the same and/or
denature after the same time which wouldn’t prove as useful results. Furthermore, it may be
difficult to keep a controlled environment for the 0°C, 80°C and 100°C.
Time constraints: water baths were being used for other research and experiments which
meant for a longer wait until they were done and until the bath reached the desired
temperature.
Equipment:
- 12 boiling tubes
- Amylase solution (20ml)
- Starch solution (100ml)
- 2 Test tube stand
- Measuring cylinder (10cm3)
- 6 beakers (250 ml)
- Thermometer
- Water bath
- Kettle
- Timer
- Iodine solution (10ml)
- Spot plate
- Pipette
, Risk assessment:
Hazards: How to mitigate: What to do if this occurs:
Broken glass- This can be To mitigate this, place any Clean cut to make sure it's
dangerous when broken and glassware away from table not infected and put a
can cause severe harm to edges. bandage or plaster on it to
someone. stop further bleeding.
Hot water- This experiment To mitigate this, have paper Put skin under cold water to
requires high temperature of towels nearby to dry off any cool the burns / sting.
water and can burn and hurt wet areas.
skin if hot water is spilled. To
mitigate this, have paper
towels nearby to dry off any
wet areas.
Amylase solution- Can cause Stay in a well-ventilated area Step outside of room to get
eye irritation or problems with safety goggles on. fresh air and wash out eyes
regarding inhalation. with clean and cold water if it
irritates your eyes.
Starch solution- Can cause stay in a well-ventilated area Step outside of room to get
eye irritation or problems with safety goggles on. fresh air and wash out eyes
regarding inhalation with clean and cold water if it
irritates your eyes.
Safety gear: Reason:
Safety goggles This will protect eyes from any solution or
steam from the high temperature water
baths and beakers.
Gloves Hands and skin will be protected from the
solutions or any hot temperature water from
burning skin.
Preparation of amylase: 1% of amylase had to be made so 1g of amylase powder was mixed
with 100ml of distilled water.
Learning aim D: Review the investigative project using correct scientific principles.
Learning aim C: Safely undertake the project, collecting, analysing and presenting the results.
Investigation of the effect of temperature on enzyme activity (Biology)
Consent and confidentiality: none needed
Abstract: To see how temperature effected enzyme activity. Starch was the product to be
broken down by amylase which was the enzyme while using iodine as an indicator of whether
the trial was successful or not. The prediction was that the time taken to break the starch (in
other words see a colour change of iodine) would decrease as the temperature increased from
0°C towards 100°C. It was also stated that the optimum would be around 40°C.
Rational:
The aim was to investigate the effect of temperature on enzymes. The reason this topic was
chosen was because enzymes are involved in almost everything but is mainly thought of
enzymes relating to the digestive system hence, why enzymes were decided. The intention was
to find out the optimum temperature on an enzyme and why the optimum was that specific
temperature. A theory that was to be investigated was that the optimum temperature was 37°C
for the specific enzymes chosen (amylase and starch). The objective was to obtain results that
closely mirror similar human environments the enzymes operate in.
Investigation: The effect of temperature on enzyme activity
Aim: To see the effect of temperature on amylase against starch.
Independent variable (the variable that was changed): Temperature
Dependant variable (the variable that was being measured): Time it takes for iodine to change
colour
Control variable (the variable that was kept the same throughout the experiment): Enzyme
solutions
Extraneous variable: Inconsistent temperatures of the solutions
Hypothesis: As the temperature changes, the enzyme activity changes but in accordance with
what the best temperature e.g., 40°C amylase worked at to break down starch at the pH of 7.
,Prediction: The best temperature for the experiment was to undergo at around 40°C because
it's close to 37°C which is the normal body temperature. The reason for 37°C is because it's the
natural body temperature due to homeostasis and evolution, the enzymes in human bodies
adapted to thrive in that environment.
Null hypothesis: The temperature does not catalase the amylase.
Potential limitations of the experiment: After 40°C the results may seem the same and/or
denature after the same time which wouldn’t prove as useful results. Furthermore, it may be
difficult to keep a controlled environment for the 0°C, 80°C and 100°C.
Time constraints: water baths were being used for other research and experiments which
meant for a longer wait until they were done and until the bath reached the desired
temperature.
Equipment:
- 12 boiling tubes
- Amylase solution (20ml)
- Starch solution (100ml)
- 2 Test tube stand
- Measuring cylinder (10cm3)
- 6 beakers (250 ml)
- Thermometer
- Water bath
- Kettle
- Timer
- Iodine solution (10ml)
- Spot plate
- Pipette
, Risk assessment:
Hazards: How to mitigate: What to do if this occurs:
Broken glass- This can be To mitigate this, place any Clean cut to make sure it's
dangerous when broken and glassware away from table not infected and put a
can cause severe harm to edges. bandage or plaster on it to
someone. stop further bleeding.
Hot water- This experiment To mitigate this, have paper Put skin under cold water to
requires high temperature of towels nearby to dry off any cool the burns / sting.
water and can burn and hurt wet areas.
skin if hot water is spilled. To
mitigate this, have paper
towels nearby to dry off any
wet areas.
Amylase solution- Can cause Stay in a well-ventilated area Step outside of room to get
eye irritation or problems with safety goggles on. fresh air and wash out eyes
regarding inhalation. with clean and cold water if it
irritates your eyes.
Starch solution- Can cause stay in a well-ventilated area Step outside of room to get
eye irritation or problems with safety goggles on. fresh air and wash out eyes
regarding inhalation with clean and cold water if it
irritates your eyes.
Safety gear: Reason:
Safety goggles This will protect eyes from any solution or
steam from the high temperature water
baths and beakers.
Gloves Hands and skin will be protected from the
solutions or any hot temperature water from
burning skin.
Preparation of amylase: 1% of amylase had to be made so 1g of amylase powder was mixed
with 100ml of distilled water.
