B2.3 - Enzymes Flashcards
What is a protein?
A long chain of amino acids.
What do proteins do?
They act as:
- structural components of tissues
- hormones
- antibodies
- catalysts
What are enzymes?
Large protein molecules that act as a biological catalyst.
How do enzymes work?
- The substrate fits into the active site of the enzyme.
- The enzyme and substrate bind together.
- The reaction takes place rapidly and the products are released from the surface of the enzyme.
- The enzyme is then ready to use again.
What do enzymes do?
- Building large molecules from smaller ones.
- Changing one molecule into another.
- Breaking down large molecules into smaller ones.
http://adf.ly/1a6xOc
Why does milk go off?
Enzymes in bacteria break down the protein structure.
What are the two main factors that affect enzymes?
- Temperature
- pH level
What is the temperature at which most enzymes denature?
40C
What is the relationship between temperature and the rate of reactions controlled by enzymes?
As the temperature increases, the rate of reaction increases up to a point.
http://adf.ly/1a6xOc
What is denaturing?
When the temperature is too high, the amino acids unravel therefore changing the shape of the active site rendering the enzyme useless.
What is the optimum temperature for human enzymes?
36.5C
Where is pepsin found?
The stomach
Where is amylase found?
The pancreas
http://adf.ly/1a6xOc
Why does the pH level denature enzymes?
Forces hold the folded chains of amino acids together and a change in pH affects the forces changing the shape of the active site.
Why can’t enzymes be killed?
They are non-living.
What do digestive enzymes do?
They break down large insoluble molecules.
What does the stomach do?
It squeezes and breaks up food into smaller pieces with a large surface area. It mixes food with the digestive juices to enable contact with enzymes.
Where are enzymes made?
Specialist glands:
- salivary glands
- Pancreas
- Lining of the gut
http://adf.ly/1a6xOc