BIO1101 - Module 3 (Enzymes)

Question 1

Module 3 (Enzymes Quiz) - Since most reactions could not occur at an appreciable rate without catalysis by enzymes, cells can control metabolism by:

Answer 1

Activation or inhibition of enzymes

Question 2

Module 3 (Enzymes Quiz) - What can feedback inhibition prevent?

Answer 2

A cell wasting chemical resources

Question 3

Module 3 (Enzymes Quiz) - The 3D structure of an enzyme is related to physical factors such as temperature and pH, since these factors may change the chemical bonds that _______ the shape of the enzyme

Answer 3

Stabilise

Question 4

Module 3 (Enzymes Quiz) - What is allosteric regulation?

Answer 4

Where molecules alter an enzymes functional site by binding onto it at another site

Question 5

Module 3 (Enzymes Quiz) - What is the optimal pH for an enzyme inside the human stomach?

Answer 5

2

Question 6

Module 3 (Enzymes Quiz) - What is it called when a subtrate binds to an enzyme?

Answer 6

Enzyme-substrate complex

Question 7

Module 3 (Enzymes Quiz) - The active site of an enzyme has a precise 3D shape, in which certain chemical groupings are arranged in such a way as to encourage a substrate molecule to change to the ____________ state

Answer 7

Transition

Question 8

Module 3 (Enzymes Quiz) - What shape is the active site of the enzyme?

Answer 8

3D shape

Question 9

Module 3 (Enzymes Quiz) - Enzyme catalysed reactions are grouped into:

Answer 9

Metabolic pathways

Question 10

Module 3 (Enzymes Quiz) - What is the ‘cofactor’ that many enzymes require to aid their function?

Answer 10

Metals or vitamins

Question 11

Module 3 (Enzymes Quiz) - Enzymes ma act to lower the activation energy of a reaction by way of:

a. providing an amino acid which briefly participates in the reaction
b. providing a template on which the substrates can more efficiently come together
c. providing a microclimate which is more conducive for the reaction to occur
d. all of the above

Answer 11

d. All of the above

Question 12

Module 3 (Enzymes Quiz) - Metabolic control in a cell can be achieved :

a. by separating groups of enzymes into compartments
b. through structural mechanisms such as grouping enzymes into multi-enzyme assemblies
c. at the level of individual enzymes
d. all of the above

Answer 12

d. All of the above

Question 13

Module 3 (Enzymes Quiz) - Which if the following IS NOT a factor on which the rate of an enzyme-catalysed reaction may depend:

a. amount of substrate
b. amount of inhibitor compounds if they are present
c. the time of day
d. amount of enzyme

Answer 13

c. The time of day

Question 14

Module 3 (Enzymes Quiz) - Feedback inhibition may occur when the end product of a metabolic pathway binds to an enzyme which reacts ________ that pathway

Answer 14

Early in

Question 15

Module 3 (Enzymes Quiz) - The rate of the enzyme catalysed reaction is related to the amount of enzyme and also to

Answer 15

The amount of substrate

Question 16

Module 3 (Enzymes) - What do enzymes do?

Answer 16

They are biological catalysts (mostly proteins) and speed up metabolic reactions by lowering energy barriers.

They are not consumed in a reaction but can speed up a reaction.

Question 17

Module 3 (Enzymes) - All chemical reactions have to have an ______ that can speed up that reaction (ie catalase for Hydrogen Peroxide).

Answer 17

Enzyme

Question 18

Module 3 (Enzymes) - What are the two types of inhibition?

Answer 18

i) Competitive - Blocking the active site of the enzyme

ii) Allosteric - changing the shape