Download Enzymes (Quick Questions) 1. What are proteins? 2. Describe 4

Enzymes (Quick Questions)
1.
What are proteins?
2.
Describe 4 functions of proteins in the body
3.
What is a catalyst?
4.
What is an enzyme?
5.
Describe the structure of an enzyme.
6.
In the body, what are enzymes involved in?
7.
How do enzymes act to speed up reactions in your body?
8.
Name 2 factors that can effect enzyme action.
9.
What does it mean if an enzyme is denatured?
10. What is meant by the optimum temperature or pH?
11. What temperature do most human enzymes work best at?
12. How does temperature effect enzyme action?
13. How does pH effect enzyme action?
Enzymes (Quick Answers)
1.
Proteins are long chains of amino acids.
2.
a. They act as structural components such as muscles and tendons.
b. They act as hormones such as insulin.
c. They act as antibodies, which destroy pathogens.
d. They act as catalysts in the form of enzymes.
A substance that speeds up a chemical reaction without being changed or
used up itself.
Enzymes of special biological catalysts that speed up reactions.
3.
4.
5. Enzymes are large protein molecules. The long chains of amino acids are
folded to produce a molecule with a specific shape (the active site). The
active site allows other molecules (substrates) to fit into the enzyme.
6. Enzymes are involved in: a. Building large molecules from lots of smaller
ones b. Changing one molecule into another c. Breaking down large molecules
into smaller ones.
7. Substrate molecule(s) arrive at the active site. They fit perfectly
together, like a lock and key. The substrate molecules react and change
shape. The products leave the active site. The enzyme is left unchanged and
ready to catalyse the next reaction.
8. a. Temperature b. pH
9. When an enzyme is denatured the shape of the active site is lost, so it
does not work properly anymore.
10. This is the temperature or pH that the enzyme works best at and where
the rate of reaction is as fast as possible.
11. 370C (the temperature of our bodies).
12. After temperatures of 400C the protein structure of the enzyme is
affected. The long amino acid chains begin to unravel. As a result, the
shape of the active site changes (is denatured). It can no longer act as a
catalyst, so the rate of reaction drops dramatically.
13. The shape of the active site of an enzyme comes from forces between the
different parts of the protein molecules. These forces hold the folded
chains in place. A change in pH affects these forces. That’s why it
changes the shape of the molecule. As a result, the active site is lost, so
the enzyme can longer work as a catalyst.