Lesson 6: Digestive enzymes

Question 1

What are enzymes?

Answer 1

Enzymes are large protein molecules with specific active sites that cataylse specific reactions, without being used up.

Question 2

What is the enzyme, substrate and product for starch?

Answer 2

Enzyme: Amylase
Substrate: Starch
Product: Sugars ie glucose

Question 3

What is the enzyme, substrate and product for protein?

Answer 3

Enzyme: Protease
Substrate: Protein
Product: Amino acids

Question 4

What is the enzyme, substrate and prodcut for fats?

Answer 4

Enzyme: lipase
Substrate: lipids/ fats
Product: fatty acids and glycerol

Question 5

What is the active site in an enzyme?

Answer 5

The specific part of the enzyme that a substrate can attach/ fit to.

Question 6

Where is amylase produced?

Answer 6

• Salivary glands
• Small inestine
• Pancreas

Question 7

Where is protease produced?

Answer 7

• Stomach
• Small intestine
• Pancreas

Question 8

Where is lipase found?

Answer 8

• Small intestine
• Pancreas

Question 9

What is the shape of the enzyme and substrate together known as?

Answer 9

• Enzyme - substrate complex.

Question 10

What do most enzymes end in?

Answer 10

• ase

Question 11

Why does temperature increase enzyme action?

Answer 11

• Enzyme and substrate gain kinetic energy.
• Collide more often
• Rate of reaction increases

Question 12

What is the temperature that gives the fastest rate of reaction known as?

Answer 12

• Optimum Temperature

Question 13

What does optimum temperature mean?

Answer 13

• The temperature that gives fastest rate of reaction between substrate and enzyme as there is the maximum frequency of collisions between substrate and enzyme.

Question 14

What happens when the temperature enzymes are in is too high?

Answer 14

• Enzyme denatures
• Active site breaks down
• Chemical bonds broken
• Substrate will no longer fit
• Enzyme can longer catalyse the reaction.

Question 15

What is meant by the term “denature?”

Answer 15

• Denature means to change an enzyme’s active site shape.

Question 16

What happens to the rate of reaction when there is an optimum pH?

Answer 16

• FASTEST rate of reaction.

Question 17

Explain in full detail how PH affects enzymes.

Answer 17

• If the PH is too high or too low it can interfere with bonds holding the enzyme together.
• This causes the active site to change shape, denatures.

Question 18

What is created when an enzyme and substrate combine together?

Answer 18

Enzyme - substrate complex

Question 19

Where are enzymes involved in aerobic respiration found?

Answer 19

• Found in mitochondria

Question 20

Name 3 processes that are catalysed by enzymes

Answer 20

• Respiration
• Digestion
• photosynthesis

Question 21

Is it possible to kill enzymes?

Answer 21

• No, they are not living

YOU CAN DENATURE THEM THOUGH.

Question 22

What codes for proteins in our body?

Answer 22

• DNA codes for proteins.

Question 23

What are proteins used for?

Answer 23

• Used for growth and repair

BECAUSE WE ALL GROW, WE ARE MADE UP OF PROTEINS

Question 24

What is actually breaking in the active site when an enzyme denatures?

Answer 24

The amino- acid bonds are breaking.

Question 25

What is an enzyme's structure? | WHAT IS IT MADE FROM....

Answer 25

Made of long- chains of amino- acids (proteins), folded to form a specific 3D shape.

Question 26

Can one particular enzyme be used to catalyse several different reactions?

Answer 26

No - each enzyme catalyses a specific type of reaction

Question 27

What 3 main roles do enzymes have?

Answer 27

1.) Build large molecules from small ones 2.) Break down large molecules into small ones 3.) Change molecule into another.

Question 28

What 2 things are needed for a chemical reaction to take place? | COLLISION THEORY

Answer 28

- Particles must collide - With sufficient amount of energy

Question 29

Give 4 uses of proteins in our body.

Answer 29

- Muscle (protein fibres) - Hormones - Enzymes - Make up chromosomes

Question 30

What are proteins?

Answer 30

- Long chains of amino acids

Question 31

How do enzymes behave at low temperatures?

Answer 31

- Don’t have enough energy - Slow down rate of reaction - Reaction eventually stops.

Question 32

What is metabolism?

Answer 32

- Metabolism is the sum of all reactions in a cell or in the body.

Question 33

# Q.) Give 3 factors that affect metabolism other than physical acitivity.

Answer 33

1.) Age 2.) Gender 3.) Genetics

Question 34

# Q.) (b) Enzymes speed up chemical reactions. Explain how amylase breaks down starch. (3)

Answer 34

- Amylase has active site SPECIFIC to starch. - Starch binds onto active site. - Starch bonds are broken down by amylase.

Question 35

What is the function of enzymes?

Answer 35

Enzymes convert food into small, soluble molecules that can be absorbed by the bloodstream.

Question 36

What are proteins? What are carbohydrates? What are lipids?

Answer 36

P: long- chain of amino acids. C: long- chain of simple sugars. ie. glucose. L: A molecule of glycerol attached to 3 molecules of fatty acids

Question 37

# Q.) The Pupils left a testube, initially 0 degrees celcius, in a water bath for an extra 24 hours to reach 40 degrees. What pH would you expect contents to be? Why?

Answer 37

- Strong acid - Enzyme isn't denatured, still works at 40 degrees celcius.