1. Enzyme Function
D. Crowley, 2007

2. Enzyme Function To know what can affect how well an enzyme works
Tuesday, July 03, 2018
Enzyme Function
To know what can affect how well an enzyme works

3. Absorption
Digested food molecules are absorbed through the small intestine (into our blood)
Once in the blood, the digested food molecules are carried around the body, to where they are needed
Only small, soluble molecules can pass through the wall of the small intestine

4. Villi
The inside wall of the small intestine needs to be thin, with a really big surface area
This allows absorption to happen quickly and efficiently (so we absorb as much food as possible)
To get a big surface area, the inside wall of the small intestine is lined with tiny villi (one of them is called a villus)
These stick out and give a big surface area. They also contain blood capillaries to carry away the absorbed food molecules.

5. Enzyme Function
Enzymes only break down one type of food – e.g. lipase only breaks down fat (lipids); amylase only breaks down carboydrates; protease only breaks down protein
The rate at which enzymes break food down can be affected by two main factors: - pH
Temperature
What do you think the optimum temperature if for enzymes in the body?
What about pH?

6. Experiment Trypsin is an enzyme which breaks down protein
If Trypsin is added to milk it will break down the milk, turning it from cloudy to translucent
You need to carry out an experiment to find out how the temperature of the Tryspin affects how quickly the milk is broken down
You will have 3 boiling tubes of milk
To each you will add some Tryspin which is at different temperatures
You need to time how long the solution went from being cloudy to translucent

7. Procedure
Take 3 boiling tubes, and fill them each with 10ml of milk – place them in a rack
Add 10ml of cold Trypsin to one boiling tube with milk in, and begin the timer – time how long it takes for the solution to become transparent
Repeat this with the second boiling tube, but this time add 10ml warm Trypsin
Repeat this with the third boiling tube, but this time add 10ml boiling Trypsin
Record all your results

8. Explanation
Explain why when the Trypsin was cold the solution turned clear slowly
Explain why when the Trypsin was warm the solution turned clear quickly
Explain why boiling the Trypsin caused the solution to remain cloudy

9. Temperature
This experiment shows that enzymes work best at a given different
If it is too cold the enzyme takes a long time to break the food molecules down
But if it is too hot the enzyme may not function at all – it has been denatured
Enzymes in the human body usually denature above 45oC