Mitochondria Biochemistry

Question 1

Which energies are involved in the body?

Answer 1

Movement = mechanical
Metabolism = chemical
Heat generation = chemical
Nerve transmission = chemical

Question 2

What does all energy production depend on in the body?

Answer 2

ATP

Question 3

What are the components of ATP?

Answer 3

Adenine
Ribose
3x Pi

Question 4

What are the bonds between ribose and phosphate group?

Answer 4

Phosphate ester bond

Question 5

What bond is between the phosphate groups?

Answer 5

Phospho-anhydride bond

Question 6

What happens in hydrolysis of ATP?

Answer 6

ATP —-> ADP + energy

Question 7

Do hydrolysis of ATP require or release energy?

Answer 7

Release

Question 8

Why are anhydride molecules high energy?

Answer 8

Very susceptible to hydrolysis thus cleavage

Release lots of energy

Question 9

What is Gibbs free energy equation at RTP?

Answer 9

ΔG = ΔH - TΔS

Question 10

What do acetic anhydrides react with OH to form?

Answer 10

Esters

Question 11

What is acetic anhydrides bond type?

Answer 11

Stable BUT unstable

Question 12

Why is acetic anhydride that bond type?

Answer 12

Breakdown rapidly BUT release good supply of energy

Negative value = breakdown spontaneous

Question 13

What is ATP hydrolysis directly linked to?

Answer 13

Endergonic reactions

Question 14

How does linking happen?

Answer 14

Through shared intermediate

One product used as reactant in 2nd reaction

Question 15

How is ATP involved in NaK?

Answer 15

ATP transfers 1xPi to pump
Phosphorylated pump unstable = changes shape
= releases Na+
K+ bind to pump = Pi removed 
= protein unable to change shape
= releases K+

Question 16

What is the site if ATP production?

Answer 16

Mitochondria

Question 17

Describe e- transport chain

Answer 17

Located in mitochondria

Complexes I, II, III, IV + V

Question 18

What are the e- carriers?

Answer 18

NADH

NAD

Question 19

What happens in e- chain?

Answer 19

NAD+ + H+ + 2e- ⇌ NADH
FAD + 2H+ +2e- ⇌ FADH
GENERATES e-

Question 20

What is the energy from e- transport chain used to do?

Answer 20

Pump H+ into intermembrane space

Question 21

Describe what happens at proton pump

Answer 21

Electrical + chemical gradient of H+ between intermembrane space + matrix
Through ATP synthase
ADP —-> ATP

Question 22

What happens in glycolysis?

Answer 22

Glucose phosphorylated

Question 23

What is glucose phosphorylated to?

Answer 23

Glucose-6-phosphate
Phospho-glucose-isomerase rearranges glucose into fructore-6-phosphate
Pi added from ATP
Fructose splits = dihydroxyacetone phosphate + glyceraldehyde-3-phosphate
DHAP —-> glyceraldehyde-3-phosphate
2 reactions occur simultaneously
GA3P oxidised
NAD+ reduced to NADH + H+
1,3 biphosphoglycerate donates 1 Pi to ADP = 3-phosphoglycerate + ATP
Phosphoglycerate loses H2O = phosphoenolpyruvate
PEP donates Pi to ADP = ATP
PEP converted to pyruvate

Question 24

How many ATP is needed to phosphorylate glucose?

Answer 24

1

Question 25

What happens after glycolysis if O2 present?

Answer 25

Pyruvate oxidised = CO2 + ATP
NADH pass e- onto ETC
= regenerates NAD+ for glycolysis

Question 26

What happens after glycolysis if no O2 present?

Answer 26

NADH donates e- to acceptor molecule

DOESN’T make ATP BUT regenerate NAD+

Question 27

When is lactic acid produced?

Answer 27

Anaerobic respiration

Question 28

How is lactic acid produced?

Answer 28

NADH accumulates due to O2 shortage
Needs to be removed
= pyruvate takes up 2xH from NADH
= lactate + NAD+