CB1E/F/G Enzymes Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is an enzyme

A

A biological catalyst that controls reactions in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How can you make a reaction happen more quickly

A

By raising the temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do enzymes do in the body

A

They enable cellular reactions to take place at lower temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the substrate

A

The molecule changed in the reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the active site of an enzyme

A

The region of an enzyme which a substrate molecule binds onto and catalyses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why are enzymes described as having ‘high specificity’ for their substrate

A

Because only enzymes with a specific complementary shape can fit into an enzymes active site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the ‘lock and key’ model

A

Substrate collides with enzymes active sight
Enzyme binds
Substrate converted to products
Products released from the active sight are now free to bind to another substrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What three factors affect the rate of an enzyme reaction

A

Temperature
pH
Substrate concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does increasing temperature affect the rate of an enzyme reaction

A

Temp increases so molecules have more KE
Movement of molecules increase
Collision increases
Enzyme substrate complexes form
Rate of reaction increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain how increasing the temperature above the optimum affects the rate of an enzyme controlled reaction

A

Temperature increases above the optimum
Increased vibrations break bonds in enzyme’s structure
Active sight changes shape, enzyme is denatured
No more enzyme-substrate complexes can form
Rate of reaction decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Graph to show effect of increasing temperature on the rate of an enzyme-catalysed reaction

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Explain how pH affects the rate of an enzyme

A

Enzymes have an optimum pH
pH shifts from the optimum
Bonds in the enzyme’s structure are altered
Active sight changes shape, enzyme is denatured
Rate of reaction decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Draw a graph to show the effect of increasing pH on rate of enzyme catalysed reaction

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Explain how the substrate-concentration affects the rate of an enzyme reaction

A

Substrate concentration increases
Number of substrate molecules in the same volume increases
Probability of a successful collision increases
More enzyme-substrate complexes form
Rate of reaction increases
Once all active sites become full, the rate of reaction plateaus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Draw a graph to show the effect of increasing substrate concentration on the rate of an enzyme-catalysed reaction

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why must large organic molecules be broken down into smaller, simpler molecules in the body

A

Large molecules are broken down into smaller molecules for absorption into the bloodstream

17
Q

Give an example of the breakdown of large molecules in plants

A

Starch is broken down by enzymes into simple sugars which are respired to release energy

18
Q

What types of molecules are proteins and carbohydrates

A

Polymers

19
Q

What are the monomers of carbohydrates

A

Simple sugars

20
Q

Which group of enzymes catalyses the breakdown of carbohydrates

A

Carbohydrases

21
Q

Which type of carbohydrate catalyses the breakdown of starch

A

Amylase

22
Q

What are the monomers of proteins

A

Amino Acids

23
Q

Which type of enzyme catalyses the breakdown of proteins

A

Proteases

24
Q

What is the function of lipases

A

Enzymes which catalyse the breakdown of lipids into fatty acids and glycerol

25
Q

Why are small molecules synthesised into larger organic molecules in the body

A

Large molecules are used for storage or are used to build structures

26
Q

Which enzyme catalyses the formation of glycogen from glucose

A

Glycogen synthase