Unit 1 - Chapter 2 Role of Enzymes Flashcards Preview

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Flashcards in Unit 1 - Chapter 2 Role of Enzymes Deck (31)
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1
Q

Enzymes are biological

A

catalysts

2
Q

Catalysts speed up chemical reactions without being

A

affected themselves

3
Q

When enzymes build up large molecules it is called a

A

synthesis reaction

4
Q

When enzymes break down large molecules it is called a

A

degradation reaction

5
Q

An active site of an enzyme is specific to only one

A

substrate

6
Q

Enzymes are made of protein so are affected by

A

temperature and pH

7
Q

At a low temperature there are few collisions between

A

substrate and enzymes so the reaction is low

8
Q

As temperature increases so does

A

the rate of reaction

9
Q

The reaction rate reaches its maximum when the temperature reaches

A

optimum

10
Q

At a temperature past optimum the enzyme protein begins to

A

denature

11
Q

Enzymes are active within a narrow ph

A

range

12
Q

Most enzymes have an optimum pH which is

A

neutral or slightly alkaline

13
Q

The exception to the optimum pH is pepsin which has an optimum of

A

pH 2

14
Q

Enzymes control biochemical pathways both

A

inside and outside the cell

15
Q

Essential metabolic pathways can be stopped if a mutation

A

codes for an ‘enzyme’ of the wrong shape

16
Q

PKU is an example of a

A

inherited disorder

17
Q

PKU is when an essential metabolic pathway is

A

prevented by the absence of an enzyme

18
Q

The activity of an enzymes increases as the substrate

A

concentration increases

19
Q

Substrate concentration gives a reaction rate increase until

A

all the active sites are working at their maximum rate

20
Q

The rate of reaction increases as the enzyme concentration increases as

A

there are more active sites for substrate molecules.

21
Q

A competitive enzyme inhibitor has a similar shape to the

A

substrate and so competes for the active site of the enzyme

22
Q

As the proportion of competitive inhibitor to substrate increase the

A

rate of reaction decreases

23
Q

A non competitive enzyme inhibitor binds to the enzyme permanently and changes the shape of the

A

active site which prevents substrate molecules from binding.

24
Q

A non competitive inhibitor produces

A

non functional enzymes

25
Q

Non-competitive inhibitors reduce the rate of reaction whatever the

A

substrate concentration

26
Q

An example of non-competitive inhibition is

A

lead

27
Q

Lead is a non-competitive inhibitor which

A

slows down the reaction rate of the enzyme catalase

28
Q

Many enzymes depend on co-factors such as

A

mineral ions or vitamins

29
Q

Digestive enzymes for example Trypsin are converted from

A

inactive to active state by another enzyme

30
Q

Vitamins are used to make co-enzyme molecules essential for

A

the activity of some enzymes e.g. the hydrogen acceptor NAD

31
Q

A variety of mineral ions are essential cofactors to activate

A

a number of enzymes e.g. iron in catalase