Body Systems: Digestion (Enzymes)

Question 1

The human body functions at what temperature?

Answer 1

37 degrees Celsius.

Question 2

What do proteins do when they are in contact with too much heat?

Answer 2

Denature (change shape and stop working).

Question 3

What are catalysts?

Answer 3

Enzymes are catalysts that speed up the rate of reaction in your body without increasing the temperature.

Question 4

Can catalysts be used again?

Answer 4

Yes.

Question 5

What are enzymes?

Answer 5

Proteins that are specialized for specific tasks. Ex) sucrase breaks down sucrose, lipases break down lipids.

Question 6

What do all chemical reactions in living organisms need to work?

Answer 6

Enzymes.

Question 7

Enzymes:

Answer 7

Build molecules (synthesis), break down molecules (digestion), speed up reactions (catalysts).

Question 8

What is activation energy?

Answer 8

The energy needed for reactants to form a product. This is so chemical bonds can be changed.

Question 9

What reduces the reactions activation energy?

Answer 9

Enzymes.

Question 10

What is a substrate?

Answer 10

The molecule on which an enzyme works. Each substrate combines to a specific enzyme and are changed during the reaction as a product is formed.

Question 11

What is an active site?

Answer 11

The area that joins the enzyme with the substrate molecule. Each enzyme has a specially shaped active site.

Question 12

What is an enzyme-substrate complex?

Answer 12

When an enzyme joins with the substrate.

Question 13

What happens to enzymes when your body temperature is too high?

Answer 13

Bonds are too weak to maintain enzyme shape.

Question 14

What happens to enzymes when your body temperature is too low?

Answer 14

Bonds are not flexible to allow the substrate to fit properly.

Question 15

What pH do humans function on?

Answer 15

6-8.

Question 16

Is stomach pH high or low?

Answer 16

Very low.

Question 17

What is substrate molecule concentration?

Answer 17

Where the greater number of substrate molecules, the greater number of collisions (the greater the rate of reaction).

Question 18

What are competitive inhibitors?

Answer 18

Molecules that have similar shapes to the substrate and compete with substrates for the active site of enzymes.

Question 19

What is the result of competitive inhibitors?

Answer 19

Enzyme activity inhibited. (No reaction/product).

Question 20

What do non-competitive inhibitors do?

Answer 20

They bind to the enzyme not at its active site, and this changes the shape of the active site of the enzyme so that the substrate cannot bind.

Question 21

What is the result of a non-competitive inhibitor?

Answer 21

Enzyme activity inhibited. (No reaction/product is made).

Question 22

What side does the molecule in non-competitive inhibiting attach to?

Answer 22

The allosteric/regulatory side.

Question 23

What is feedback inhibition?

Answer 23

A series of enzymatic reactions where the product of the first reaction becomes the substrate for the next reaction. The final product can go back and bind to the allosteric side of the first enzyme to prevent the substrate and enzyme from binding.

Question 24

What is the result of feedback inhibition?

Answer 24

This slows down reaction rates, preventing further creation of final products.

Question 25

What changes to form a product in a chemical reaction: the enzyme or the substrate?

Answer 25

The substrate.

Question 26

What is an uncompetitive inhibitor do?

Answer 26

It binds only to the enzyme-substrate complex and does not bind to a free enzyme. It is ineffective at low substrate concentration.