Enzymes

Question 1

all chemical reactions that occurs within an organism

Answer 1

metabolism

Question 2

simpler substance combined to form complex substances

- endergonic reaction

Answer 2

anabolism-

Question 3

• complex substance broken down to form simpler substance

- exergonic reaction

Answer 3

catabolism

Question 4

example of anabolism

Answer 4

synthesis of glycogen

Question 5

example of catabolism

Answer 5

hydrolysis of glycogen

Question 6

function of catalyst

Answer 6

speed up chemical reaction but stay unchanged at the end of the reaction

Question 7

6 characteristics of an enzyme

Answer 7

has catalytic properties, specific active site, reversible reaction, enzyme specificity, very efficient, affected by many factors

Question 8

types of enzyme specificity

Answer 8

absolute specificity, group specificity, linkage specificity

Question 9

absolute specificity

Answer 9

catalyze only one reaction

Question 10

act only on specific functional group.

eg; amino, methyl, phosphate

Answer 10

group specificity

Question 11

act on particular type of chemical bond

Answer 11

linkage specificity

Question 12

how does an enzyme speed up chemical reactions?

Answer 12

by lowering the activation energy

Question 13

• unstable condition
• substrate activated; breaking and making bonds can occur
• increases the chances of successful collision

Answer 13

what happens at transition state

Question 14

energy is released
ΔG < 0
reactants > products

Answer 14

exergonic reaction

Question 15

energy is absorbed
ΔG > 0
reactants < products

Answer 15

endergonic reaction

Question 16

energy generated by catabolic process used by cells to perform anabolic process

Answer 16

energy coupling

Question 17

how to lower the activation energy

Answer 17

• orienting substrates correctly
• straining substrate bonds
• provide favorable microenvironment

Question 18

the active site in the enzyme has a fixed, rigid and geometrical conformation

Answer 18

lock & key model

Question 19

active site changes shape so that substrate can fit into it

Answer 19

induced fit

Question 20

only substrate with complementary shape can accommodate the site

Answer 20

lock & key model

Question 21

substrate with non-complementary shape can accommodate the site

Answer 21

induced fit

Question 22

active site will return to its original shape when the product is released

Answer 22

induced fit

Question 23

6 factors influencing enzyme activity

Answer 23

pH value, temperature, substrate concentration, enzyme concentration, cofactor, inhibitor

Question 24

below optimum temperature

Answer 24

reaction will increase as the temperature increases until it reaches the optimum temperature

Question 25

above optimum temperature

Answer 25

enzyme will be denatured and lose its catalytic properties

Question 26

atom in enzyme will vibrate violently, breaking the bonds which held the enzyme in shape.

Answer 26

above optimum temperature

Question 27

enzyme concentration

Answer 27

reaction will increase as the enzyme concentration increases

Question 28

rate of reaction increases with increasing substrate concentration up to the

Answer 28

point of saturation.

Question 29

2 types of inhibition

Answer 29

reversible & irreversible inhibition

Question 30

molecules will bind permanently with the enzyme by covalent bond

Answer 30

irreversible inhibition

Question 31

cyanide, insecticide is the example of molecules for

Answer 31

irreversible inhibition

Question 32

2 types of reversible inhibition

Answer 32

competitive & non-competitive(allosteric site) inhibitor

Question 33

has a similar shape to natural substrate and fits temporarily on active site

Answer 33

competitive inhibition

Question 34

no structural similarities to natural substrate and attached to allosteric site

Answer 34

non-competitive inhibition

Question 35

effect can be reduced if substrate concentration increases

Answer 35

competitive inhibition

Question 36

effect cant be reduced if substrate concentration increases

Answer 36

non-competitive inhibition

Question 37

malonic acid molecule is the inhibitor for

Answer 37

competitive inhibition

Question 38

amino acid isoleucine is the inhibitor for

Answer 38

non-competitive inhibition

Question 39

example of enzyme cofactor

Answer 39

inorganic ion, prosthetic group, coenzymes

Question 40

non protein components that are bound tightly or loosely required for certain enzymes for their efficient activity

Answer 40

enzyme cofactors

Question 41

attaches temporarily | eg; zink, chlorine

Answer 41

inorganic ions

Question 42

binds tightly and permanently | eg; FAD

Answer 42

prosthetic group

Question 43

- binds loosely and temporarily - obtained from vitamins - eg; NAD+

Answer 43

coenzymes

Question 44

enzyme-protein portion

Answer 44

apoenzyme

Question 45

a non protein component

Answer 45

cofactor

Question 46

apoenzyme + cofactor =

Answer 46

haloenzyme

Question 47

a molecule that binds to an enzyme at a site other than the active site and change the enzyme activity

Answer 47

allosteric regulation

Question 48

6 classes of enzymes

Answer 48

hydrolase, oxidoreductase, transferase, lyase, isomerase, ligase

Question 49

- formation of 2 products from a substrate by hydrolysis | - lipase, amylase

Answer 49

hydrolase

Question 50

- non-hydrolytic addition or removal of groups from substrates - aldolase

Answer 50

lyases

Question 51

- rearrangement of atoms within a molecule | - glucose-phosphate isomerase

Answer 51

isomerase

Question 52

- join together 2 molecules by the break down of ATP | - phosphokinase

Answer 52

ligases

Question 53

- transfer of a functional group from one substance to another - transaminase kinase

Answer 53

transferase

Question 54

- involved in oxidation and reduction | - cytochrome oxidose

Answer 54

oxidoreductase