Brainscape's Knowledge GenomeTM

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


See full index

MEH A > Session 1 Lecture 2 > Flashcards

Session 1 Lecture 2 Flashcards

1
Q

What is the general formula of a carbohydrate?

A

(CH2O)n

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

What chemical groups do carbohydrates contain?

A

aldehyde, ketons and hydroxyl

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

What is a monosaccharide?

A

Single sugar units 3-9 carbons

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

What is a disaccharide?

A

2 sugar units together

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

What is an oligosaccharide?

A

3-12 sugar units

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

What is a polysaccharide?

A

10-1000s sugar units

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

Give an example of a monosaccharide?

A

Glucose

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

Give an example of a disaccharide

A

Sucrose

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

Give an example of a polysaccharide

A

Starch

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

What is sucrose made of?

A

Glucose and fructose

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

What is lactose made of?

A

Glucose and galactose

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

What is maltose made of?

A

Glucose and glucose

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

What is step 1 of catabolism?

A

Breakdown to building block molecules

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

Why can cellulose not be broken down by humans?

A

We don’t have an enzyme that will break down the beta 1-4 linkages present in cellulose

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

What are the different types of lactose deficiency?

A

Primary lactase deficiency, secondary lactase deficiency and congenital lactase deficiency

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

What is primary lactase deficiency?

A

Incense of lactase persistence allele

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is secondary lactase deficiency?

A

Caused by injury to small intestine e.g. coeliac disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is congenital lactase deficiency?

A

Autosomal recessive defect in lactase gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How are monosaccharides absorbed?

A

Active transport by sodium dependent glucose transported (SGLT1) into intestinal epithelial cells and then via facilitated diffusion using transport protein GLUT2 into blood supply

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the different transport proteins that can transport monosaccharides?

A

GLUT 1 - GLUT 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where are GLUT 2 transporter present?

A

Kidney, liver, pancreatic beta cells, small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where are GLUT 4 transporters present?

A

Adipose tissue, striated muscle

23
Q

What is special about GLUT 4 transporters?

A

They are insulin regulated

24
Q

All tissues can metabolise glucose, but which cells have an absolute requirement?

A

RBC, neutrophil, innermost cells of kidney medulla and lens of eye

25
Q

What is stage 2 of catabolism?

A
  • Breakdown to metabolic intermediates

- Release of ‘reducing power’ and energy

26
Q

What is another name for stage 2 of catabolism?

A

Glycolysis

27
Q

What are the two phases of glycolysis?

A

Investment and payback

28
Q

What additional enzyme do you need for glycolysis to operate anaerobically?

A

PDH

29
Q

What is produced after glycolysis?

A

2 NADH, 2 ATP and 2 pyruvate

30
Q

What is the key control enzyme in glycolysis?

A

Phosphofructokinase-1

31
Q

In glycolysis, why do you need to first phosphorylate the glucose?

A

Make glucose negatively charged and prevents passage back across plasma membrane. Also inc reactivity

32
Q

What is the committing step of glycolysis?

A

Step 3 - fructose 6P to fructose 1,6 bisP

33
Q

What is the clinical application of glycolysis?

A

Rate of glycolysis up to 200x greater in cancer

34
Q

How is phosphofructokinase regulated in muscle?

A

Allosteric regulation - inhibited by high ATP and stimulated by high AMP

35
Q

How is phosphofructokinase regulated in the liver?

A

Hormonal regulation - stimulated by insulin and inhibited by glucagon

36
Q

Why inhibits production of hexokinase?

A

G6-P

37
Q

What happens if there is high [NADH] or low [NAD+]

A

High energy level signal and causes product inhibition of step 6 and inhibits glycolysis

38
Q

What causes pyruvate kinase to increase?

A

high insulin: glucagon ration (i.e. high insulin and low glucagon)

39
Q

Name two important intermediates in glycolysis?

A

Bisphosphoglycerate mutase and glycerol 3-phosphate dehydrogenase

40
Q

What does Bisphosphoglycerate mutate do?

A

Catalyses synthesis of 2,3-bisphosphoglycerate

41
Q

What does glycerol 3-phosphate dehydrogenase do?

A

Catalyses synthesis of glycerol phosphate

42
Q

Why is glycerol phosphate important?

A

Important to triglyceride and phospholipid biosynthesis

43
Q

What would happen to glycolysis when all the NAD+ is converted to NADH?

A

Glycolysis would stop

44
Q

Normally, how is NAD+ regenerated?

A

During stage 4 of metabolism

45
Q

Why is NAD+ regenerated in a different way in RBC?

A

RBC hae no stage 3 or 4 of metabolism because they have no mitochondria

46
Q

How is NAD+ regretted in a RBC?

A

Lactate Dehydrogenase (LDH) Converts pyruvate to lactate

47
Q

What is plasma lactate concentration determined by?

A

Relative rate of proaction, utilisation and disposal

48
Q

Deficiency in which 3 enzymes can cause galactosaemia?

A

Galactokinase, uridyl transferase and UDP-galactose epimerase

49
Q

What is the pentose phosphate pathway?

A

No production of energy, main product is NADPH and ribose sugars

50
Q

What is the start material for the pentose phosphate pathway?

A

Starts from glucose 6 phosphate

51
Q

What is the rate limiting step of the pentose phosphate pathway?

A

Glucose 6 phosphate dehydrogenase

52
Q

What is NADPH required for?

A

Reducing power for biosynthesis, maintenance of GSH levels and detoxification reactions

53
Q

What is C5-sugar ribose required for?

A

Nucleotides, DNA and RNA

MEH A (19 decks)

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