Brainscape's Knowledge GenomeTM

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


See full index

Principles 2018 > Biochemistry Part 5 > Flashcards

Biochemistry Part 5 Flashcards

1
Q

What is our primary energy source?

A

Oxidised to CO2 and H20

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

Which cell types require glucose?

A 
Erythrocytes
Retina
Renal Medulla
Brain 
All cancer cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name some dissacharides

A

Lactose
Maltose
Sucrose
Cellobiose

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

Name some polysaccharides

A

Cellulose

Glycogen

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

What are the fates of glucose?

A

Storage

  • glycogen, starch, sucrose
  • conversion to lipids

Oxidation through the pentose phosphate pathway

Fermentation by anaerobic glycolysis

Oxidation through aerobic glycolysis

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

What is the outcome of the pentose phosphate pathway?

A

Formation of ribose-5-phosphate

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

What is the outcome of oxidation though anaerobic glycolysis?

A

Formation or Pyruvate

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

What is the outcome of fermentation by anaerobic glycolysis?

A

Formation of lactate

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

What is ribose-5-phostphate?

A

Precursor for nucleotide synthesis and DNA repair

Essential for growth

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

What is Lactate?

A

Rapid, inefficient ATP production

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

What is pyruvate?

A

Efficient ATP production by oxidative metabolism

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

How is glucose transported into cells?

A

Via Na+/glucose symporters

Via passive facilitated diffusion glucose transporters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is GLUT 1 found?

A

Brain

Low Km

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

Where is GLUT 2 found?

A

Liver B cells

High Km, insulin dependant

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

Where is GLUT 3 found?

A

Brain

Low Km

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

Where is GLUT 4 found?

A

Muscle
Adipose tissue
Insulin-dependant

17
Q

Where is GLUT 5 found?

A

Gut

Fructose transport

18
Q

Describe the action of GLUT 1?

A

Binding of glucose to the outside triggers a conformational change

Binding site faces inwards

Glucose can be released in the inside

Conformational change regenerates the binding site on the outside

19
Q

What is the overall reaction for glycolysis?

A

Glucose + 2ADP + 2 Pi + 2NAD+

=

2 pyruvate + 4ATP + 2 H2O + 2NADH + 2H+

20
Q

How many ATP is used in the conversion of Glucose to fructose-1,6-bisphosphate?

A

2

21
Q

How many ATP are generated in the conversion of 2 triode phosphates to 2 pyruvates?

A

4

2 NAD+ are degraded to 2NADH and 2H+

22
Q

Describe glycolysis stage 1?

A

Glucose is trapped and destabilised

23
Q

Describe glycolysis stage 2?

A

Two interconvertible three-carbon molecules are formed

24
Q

Describe glycolysis stage 3?

A

Generation of ATP

25
Q

What are the 3 control points in glycolysis?

A
  1. Hexokinase- substrate entry
  2. Phosphofructokinase- rate of flow
  3. Pyruvate kinase- product exit
26
Q

What are the activators of phosphofructokinase?

A

AMP

Fructose 2,6 bisphosphate

27
Q

What are the inhibitors of PFK?

A

ATP
(will slow glycolysis if energy abundant)

Citrate
(TCA cycle intermediate. Slows downstream energy of pyruvate into TCA cycle if energy abundant)

H+
(slows glycolysis if too much lactic acid is being produced)

28
Q

What is the energy charge?

A

The ATP/AMP ratio

29
Q

When is the cell fully charged and discharged?

A

Fully charged= all adenylate nucleotides are in the shape of ATP

Discharged= if the cell only contains AMP and Pi

30
Q

Why is AMP and not ADP the positive regulator?

A

If ATP is rapidly used up then adenylate kinase can salvage some of the energy in ADP

(2ADP = ATP + AMP)

31
Q

What is the fate of pyruvate?

A

Carbon to fuel TCA cycle in mitochondria

32
Q

What is the fate of electrons?

A

Electron transport chain and ATP synthesis

33
Q

What happens if mitochondrial metabolism is inhibited by lack of O2?

A

NADH is used to ferment pyruvate into lactic acid

NADH is re-generated at beginning of stage 3

34
Q

What is the warburg effect?

A

Cancer cells produce energy by high rate of glucose metabolism to lactate (anaerobic glycolysis)
-cancer cells have low Km Hexokinase

35
Q

What are the advantaged of the warburg effect?

A

> Rapid energy production

>Supports other pathways for 
nucleotide synthesis (needed for growth)

> Supports rapid cell growth (proliferation)

36
Q

What are the disadvantages of the warburg effect?

A

> Produces H+ and lactate as end products

> Very inefficient ATP synthesis

> High glucose consumption demand

> Cancer patients lose weight

37
Q

What could be used to treat cancer by targeting glycolysis?

A

2-deoxyglucose

2-Bromopyruvate

Dichloroacetate

Principles 2018 (34 decks)

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