Enzymes

Question 1

What are enzymes ?

Answer 1

Enzymes are biological catalyst that catalyses the metabolic/ chemical reactions in the body.

Question 2

Enzymes catalyze reaction by lowering the __________ ___________ which in turn ___________ the rate of reaction.

Answer 2

Activation energy

Increases

Question 3

What kind of proteins are enzymes ?

Answer 3

Globular proteins

Question 4

What are enzymes typically named after ?

Answer 4

The substrate it acts on or class of enzyme

Question 5

How many classification of enzymes by function are they?

Answer 5

Six

Question 6

What is metabolism?

Answer 6

Refers the all the chemical reaction in the body that’s produces energy of vital body functions.

Question 7

Enzymes control the metabolic pathways

True or False?

Answer 7

True

Question 8

____________ pathways require energy and is used to make larger molecules from smaller molecules.

___________ pathways release energy and is used to make smaller molecules from larger molecules.

Answer 8

Anabolic

Catabolic

Question 9

Example of catabolic and anabolic reaction

Answer 9

Synergies of glycogen from glucose

Break down of food in small intestine

Question 10

What is a substrate?

Answer 10

Any molecules that have a reaction catalyzed by an enzyme.

Question 11

The active site’s shape must be complimentary to that of the substrate

True or False

Answer 11

True

Question 12

What are the two theories that seek to explain how the enzyme and substrate complex is formed?

Answer 12

Lock and key hypothesis

Induced fit theory

Question 13

Explain the lock and key theory

Answer 13

Enzymes have high specificity only one enzyme to one molecule as the active site are rigid and exactly complementary to the shape of the substrate.

Question 14

Explain the induced fit theory

Answer 14

Enzyme are specific but not as specific to work on one molecule but similar classes of molecules. The active site is flexible therefore it may be adjusted the Maximize the fit one the substrate composition is specifically correct.

Question 15

Arrange the steps of the catalytic cycle

1. Lower the require energy so reaction may happen more readily
2. Release the products
3. Bring molecules close together in the correct orientation
4. Weaken and break appropriate bonds to make reaction proceed

Answer 15

3, 4, 1, 2

Question 16

What does it mean when it said enzyme are “recyclable”?

Answer 16

Enzymes remain chemically unchanged after they catalyze a reaction therefore they can be resused over and over again.

Question 17

Define co - factor and co enzyme

Answer 17

Co - factor are helper molecules for enzymes

Co enzymes - non protein components required for enzyme efficient activity.

Question 18

What are the types of co factors ?

Answer 18

Inorganic ion (Zn2+, Fe2+) that have a charge mound enzyme active site or substrate to be more compatible

Prosthetic group non protein organic group that bound permanent to the enzyme active site

Question 19

Why are the usage of inorganic ions important ?

Answer 19

The charge between substrate and exams are not always a perfect match therefore to hold them together tight enough ions with a charge are introduced and this electrostatic attraction ensures that the substrates and enzyme hold on close together.

Question 20

Inhibitors are molecules that can increase the rate of enzyme controlled reactions.

True or false ?

Answer 20

False they reduce not increase the rate

Question 21

What’s the difference between a competitive and noncompetitive inhibitor ?

Answer 21

A competitive inhibitor has a similar shape to that of the substrate that the enzyme works therefore it prevents the real substrate from binding with the active site while non competitive inhibitors binds to a parts of the enzyme other than the active site causing the active site to change shape which causes the substrate from binding with the active site.

Question 22

What are allosteric regulators ?

Answer 22

A allosteric enzymes have allosteric site different from that of that of the active site when binded they regulate the activity of the enzyme by changing its active site reversibly.

Question 23

Allosteric regulators may ___________ or _________ the rate of reaction.

Answer 23

Increase or decrease

Question 24

Match the word to its meaning
( allosteric inhibitor, allosteric activator)

Molecules that bind with the enzyme causing the substrate to fit better. __________

Molecules that change the shape of the active site causing the substrate to not be able to fit. ________

Answer 24

allosteric activator, allosteric inhibitor

Question 25

“ Enzymes catalyze specific reactions given exam catalyze only reactions of one type”

This statement speaks to what feature of enzymes.


Answer 25

Their specificity

Question 26

What are some factors that affect enzyme activity

Answer 26

Temperature

Ph

Enzyme concentration

Substrate concentration