Metabolism

Question 1

What are the 2 types of reactions in metabolic pathways

Answer 1

Anabolic

Catabolic

Question 2

Catabolic reactions

Answer 2

Breakdown of large complex organic mol. –> smaller ones.

Release of chem. energy stored in covalent bonds.

Question 3

Anabolic reactions

Answer 3

Synthesis of larger organic mol. from smaller ones.

Question 4

Are catabolic reaction exergonic or endergonic?

Answer 4

EXERGONIC

Question 5

Are anabolic reaction exergonic or endergonic?

Answer 5

ENDERGONIC

Question 6

ATP

Answer 6

Facilitates energy transfer between catabolic + anabolic reactions by storing chemical energy in its P bonds.

Question 7

Structure of ATP

Answer 7

Pentose sugar ribose

Nitrogenous base - Adenine

3 Phosphate groups

Question 8

Apoenzymes

Answer 8

Enzymes that are catalytically inactive.

Once activated, i.e by coenzymes or cofactors, known as – holoenzymes.

Question 9

Does substrate level phosphorylation require O2?

Answer 9

NO

Question 10

Where does oxidative phosphorylation occur

Answer 10

ETC

Question 11

Does oxidative phosphorylation require O2?

Answer 11

YES

Question 12

Where does the energy req. for oxidative phosphorylation come from?

Answer 12

Generated by transfer of e- from NAD+ + FAD.

Question 13

What do coenzymes FAD + NAD+ do?

Answer 13

Act as couriers by transferring e- between mol. during oxidation + reduction reactions.

Question 14

What are REDOX reactions

Answer 14

Chemical reactions involving the transfer of e- between mol.

Question 15

OXIDATION

Answer 15

Chemical reaction involving LOSS of e- through the loss of Hydrogen or the gain of O2.

Question 16

REDUCTION

Answer 16

Chemical reaction involving GAIN of e- through gain of hydrogen or loss of O2.

Question 17

What happens to the potential energy of the mol. when oxidation occurs

Answer 17

Decreases

Hence why they’re called exergonic reactions.

Question 18

What happens to the potential energy of the mol. when REDUCTION occurs

Answer 18

Increases

Hence why they’re called endergonic reactions.

Question 19

NAD+

Answer 19

Accepts + donates 2 H atoms:

1 H+ – containing 1 proton + 1 e-

1 Hydride ion – containing 1 proton + 2e-

Question 20

FAD

Answer 20

Accepts 2 H+ – each containing 1 p + 1 e-.

Question 21

In which pathways does substrate level phosphorylation occur

Answer 21

Glycolysis (cytoplasm)

Krebs cycle (mit. matrix)

== Yielding 4 mol. of ATP per mol. of glucose.

Question 22

What are the ways in which glucose can be transported across plasma membranes of a cell?

Answer 22

Secondary AT

FD

Question 23

Glucose catabolism

Answer 23

Glucose –> Pyruvic acid = Glycolysis

Question 24

What are the 2 fates of Glucose 6-phosphate

Answer 24

Skeletal muscle

Liver

Question 25

Control of glycogenolysis

Answer 25

Stimulated by hormone glucagon – secreted from pancreas

+ epinephrine, – secreted from suprarenal medulla.

Question 26

Define enzyme

Answer 26

A specific protein catalyst that accelerates the forward + reverse rates of chemical reactions w/out being consumed or changed in the reaction.