chapter 4- enzymes

Question 1

what are enzymes made up of

Answer 1

amino acids=proteins (globular proteins)

Question 2

are enzymes made up of high molecular weight

Answer 2

yes

Question 3

what do globular proteins have

Answer 3

a spherical shape, alpha helix molecules, 1y, 2y and 3y structure- hydrogen, ionic and disulphide bonds

Question 4

what do intracellular enzymes do

Answer 4

the synthesis of polymers into monomers in cells?????

Question 5

what does anabolic mean

Answer 5

building up molecules it is required for growth

Question 6

what does catabolic mean

Answer 6

breaking down molecules into sub units

Question 7

eg of work down by a catabolic enzyme

Answer 7

digestion- amalase breaks carbohydrates into starch then glucose

Question 8

eg of work down by anabolic enzymes

Answer 8

nail growth

Question 9

what are enzymes

Answer 9

biological catalysts that speed up the ror without getting used up in the reaction and changing the produced substances.

An enzyme is a protein that acts as a catalyst, increasing the rate of a biochemical reaction.
It does this by lowering the activation energy.

Question 10

what is enzymes specificity

Answer 10

the ability of an enzyme to select a specific substrate from a range of chemically similar compounds

Question 11

what is a cofactor

Answer 11

a non protein chemical compound or metallic ion that is required for the enzymes activity as a catalyst. they can be considered as helper molecules that assist in biochemical reactions

Question 11

what is a holoenzyme

Answer 11

refers to the active enzyme with its nonprotein component.

Question 11

what is an apoenzyme

Answer 11

is an inactive enzyme without its nonprotein part

Question 12

what is an enzyme

Answer 12

a protein that acts as a catalyst increasing the rate of a biochemical reaction by lowering the activation energy

Question 13

Why is the tertiary structure of enzymes important?

Answer 13

the active site has a specific tertiary structuee which is complementary to a specific substrate enabling an enzyme-substrate complex

Question 14

what is an active site

Answer 14

the group of amino acids that make up the region where a substrate fits to catalyse a reaction

An active site is the region on an enzyme where a substrate fits to catalyse a reaction
The shape of the active site is determined by the enzyme’s tertiary structure

Question 15

what does the lock and key hyphothesis state

Answer 15

that the binding of the substrate with the enzyme occurs because the active site has a shape which is complementary to the shape of the substrate meaning the substrate fits the active site like a key fits a lock

The lock and key hypothesis says that the active site and substrate have fixed shapes that are complementary

Question 16

what does the induced fit hyphothesis state

Answer 16

that the interaction between the substrate and the tertiary structure of the enzyme causes the shape of the active site to change slightly allowing the substrate to “fit”

The induced-fit hypothesis says that when the substrate starts to bind to the active site, the shape of the active site changes. This puts stress on the bonds in the substrate and makes them easier to break. This lowers the activation energy.

Question 17

what is a substrate in the context of enzymes

Answer 17

a substance that is acted on or used by another substance or process

Question 18

define activation energy

Answer 18

the energy required to bring about a reaction

Activation energy is the minimum amount of energy required to bring about a reaction.

Question 19

what is a competitive inhibitor

Answer 19

an inhibitor that binds to the active site of an enzyme

Question 20

what is a non-competitive inhibitor

Answer 20

an inhibitor that binds to an enzyme but not at the active site at an allosteric site

Question 21

what are coenzymes

Answer 21

organic molecules such as vitamins loosely bound to enzymes allowing them to by catalytic

Question 22

what are cofactors

Answer 22

inorganic ions which combine with apoenzyme to activate it forming holoenzyme

Question 23

example of a cofactor

Answer 23

chloride ion for amylase

Question 24

what is a prosthetic group

Answer 24

inorganic ion or organic molecules that are tightly bound to the enzymes

Question 25

xample of a prosthetic group for an enzyme

Answer 25

zinc ion for carbonic anhydrase

Question 26

is amylase intra or extracellular

Answer 26

extra

Question 27

is catalase intra or extracellular

Answer 27

intra

Question 28

are vitamins a source of coenzymes

Answer 28

yes

Question 29

is Cl- a cofactor for carbonic anhydrase

Answer 29

no it is for amylase

Question 30

do Both inorganic ions and coenzymes bind temporarily to enzymes.

Answer 30

yes