OCR ALevel Biology - Module 2 - Definitions - Topic 2.4 : Enzymes Flashcards

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

What is activation energy?

A

The amount of energy needed for a reaction to happen.

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

What is an active site?

A

A specific region on an enzyme where the substrate binds and the reaction takes place.

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

What is amylase?

A

An enzyme that catalyses the extracellular breakdown of starch.

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

What is catalase?

A

An enzyme that catalyses the intracellular breakdown of hydrogen peroxide into oxygen and water.

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

What is a coenzyme?

A

A type of cofactor that is bound loosely to an enzyme with weak interactions.

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

What are cofactors?

A

A non-protein molecule that is needed for the effective functioning of an enzyme.

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

What is a competitive inhibitor?

A

A molecule which binds to the active site of an enzyme and prevents the substrate from binding.

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

What is cyanide (CN-)?

A

A metabolic poison which acts as an irreversible inhibitor of cytochrome oxidase and hence preventing respiration.

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

What is end-product inhibition?

A

A method of enzyme inhibition where the product of an enzyme controlled reaction can bind to the enzyme and prevent it from working.

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

What is an enzyme?

A

A biological catalyst used to speed up the rate of biochemical reactions without being used up or permanently altered.

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

What is an enzyme-product complex?

A

The temporary complex formed after the enzyme has catalysed the reaction but before the products have left the active site of the enzyme.

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

What is an enzyme-substrate complex?

A

The temporary complex formed when the substrate binds to the active site of the enzyme.

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

What is an extracellular reaction?

A

A reaction that occurs outside of cells.

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

What is an inactive precursor?

A

An inactive form of an enzyme that cannot carry out its function until it is activated.

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

What is the induced fit hypothesis?

A

A model of enzyme action that describes how once a specific substrate binds to the active site, the enzyme undergoes subtle conformational changes to fit the substrate better.

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

What is an intracellular reaction?

A

A reaction that occurs within cells.

17
Q

What is the lock and key hypothesis?

A

A model of enzyme action that describes how the enzyme will only fit a substrate that has the correct complementary shape to the active site.

18
Q

What is metabolism?

A

The sum of all the chemical reactions taking place in a cell.

19
Q

What is a non-competitive inhibitor?

A

An inhibitor which binds to a different part of an enzyme known as the allosteric site and prevents the enzyme from functioning.

20
Q

What is a prosthetic group?

A

A type of cofactor that is bound tightly to an enzyme with strong interactions.

21
Q

What is substrate specificity?

A

The ability of an enzyme to catalyse only a specific reaction or set of reactions which have substrates complementary to the active site of the enzyme.

22
Q

What is the temperature coefficient (Q10)?

A

A method of calculating an increase in reaction rate after a 10°C temperature increase - calculated using the following equation: Q10 = R2/R1.

23
Q

What is trypsin?

A

An enzyme that catalyses the extracellular breakdown of proteins.