Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MERP BIOCHEM > Glycolysis, TCA, ETC > Flashcards

Glycolysis, TCA, ETC Flashcards

1
Q

What are the two outcomes of glycolysis depending on oxygen availability?

A

Pyruvate and lactate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Mnemonic for Glycolysis enzymes?

A 
High
Profile (isomerase)
People (Phosphorylate)
Act
Too
Glamorous (Phos. And oxidation)
Picture (ATP)
Posing
Every 
Place (ATP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the four isozymes of hexokinase?

A

Hexokinase I,II,III = low Km
Glucokinase IV = high Km (lower on graph) = only in liver, activity high after a meal, glucose is trapped as G6P in liver with high blood glucose levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s the rate determining step of glycolysis?

A

Reaction 3; F6P –> FBP (fructose-6-phosphate and fructose-1,6-bisphosphate) not readily reversible, only reversible via Fructose bisphosphatase 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which steps of glycolysis are not reversible?

A

3 and 10 (1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many ATPs are used during the energy investment phase?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How many ATP are made during the energy generating phase?

A

4 total, 2 net made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

1,3BPG has high ____

A

Energy potential for next step (step 7)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is unique about GAP? What can inhibit this?

A

Covalently bound to cysteine of enzyme GAPDH, where heavy metals (Hg2+) can irreversibly bind.

If NADH is not oxidized, rxn stops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the high energy potential steps?

A

PEP for the next reaction (rxn 9)

And

GAP for rxn 7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What hexoses other than glucose are metabolized?

A

Galactose –> G6P
Fructose –> DHAP
Mannose –> M6P –> F6P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Other fates of Pyruvate

A
  1. Aerobic = TCA cycle
  2. Anaerobic = CO2 and ethanol , nonhumans
  3. Anaerobic = lactate (fermentation= 2ATP, 100x slower than oxidative resp)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the cori cycle

A

When lactate is taken to liver and converted back to glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Control points of glycolysis (3)

A
  1. Hexokinase
  2. Phosphofructokinase 1
  3. Pyruvate kinase

All have negative delta Gs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does G6P regulate?

A

Inhibits Hexokinase I,II,III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Function of glucagon

A

Signals liver to release glycogen stores and inhibits glucokinase. Glucokinase only active when glucose levels rise

17
Q

What inhibits and regulates Phosphofructokinase?

A

ATP and citrate inhibit.
ADP and AMP relieve inhibition and activate PFK1
Regulated by glucagon

18
Q

What activates Phosphofructokinase (PFK1)

A

F2,6BP

19
Q

What inhibits hexokinase?

A

G6P

20
Q

Function of glucagon?

A

Signals liver to release glycogen stores and inhibit glucokinase

21
Q

What happens during a Fed state?

A

Insulin is released
PFK2 is dephosphorylated
High F2,6BP levels which stimulate kinase activity

22
Q

What occurs during fasting state?

A

Glucagon is released
Protein kinase A activated
Phosphorylation of PFK2
Decreased F2,6BP

23
Q

What inhibits Pyruvate kinase?

A

ATP and acetyl CoA (a sign of abundant energy in cell)

Can be inactivated by phosphorylation

Stimulated by F1,6BP

24
Q

What are the alternative pathways of glycolysis?

A

2,3 BPG Shunt

Pentose phosphate shunt

25
Q

What is the net payout for Glycolysis?

A

2 ATP, 2 NADH, 2 Pyruvate

26
Q

Two shuttles that transport cytosolic NADH into mito

A
  1. Malate aspartate shuttle

2. Glycerol phosphate shuttle

27
Q

Inhibitors of ETC (RMACCO)

A 
Rotate - Rotenone
Mouth - Malonate
And - Antimycin A
Cum - Carbon monoxide, cyanide
Orally - oligomycin
28
Q

Overall yield of TCA

A

2 CO2
3 NADH
1 FADH2
1 ATP

29
Q

Five coenzymes needed for PDH

A 
TPP (B1)
Pantothenic acid b5
Lipoamide
FAD (B2)
NAD (B3)
30
Q

How many cycles does TCA do?

A

2 because you have 2 Pyruvate from glycolysis

31
Q

Cataplerotic pathways

A

Use TCA intermediates by avoiding built up

32
Q

What are Anaplerotic pathways?

A

Make TCA intermediates

33
Q

What are the environmental inhibitors of TCA

A

Arsenate, binds sulfhydryl compounds = lipoamide

Fluoroacetate (FAC) , binds aconitase as competitive inhibitor

34
Q

Diseases associated with TCA disorders?

A

Alpha-ketoglutarate dehydrogenase
Fumarase
Succinate dehydrogenase

= cause neurological impairments, encephalitis

MERP BIOCHEM (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions