Brainscape's Knowledge GenomeTM

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


See full index

1. Theme 3 > T3 L5: Introduction to lipids > Flashcards

T3 L5: Introduction to lipids Flashcards

1
Q

What are 3 examples of labile energy stores?

A

ATP (in the phosphate groups), Redox agents (NADH, FADH2) and ionic transmembrane gradients

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

What is creatine phophate?

A

An energy store in muscles

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

Give 2 examples of large and stable energy stores

A

Carbohydraes and fats

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

What is the importance of acetyl-CoA in energy production?

A

Its an energy mediator used to begin the Krebs cycle by oxidising citric acid

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

What molecule is cholesterol produced from?

A

Acetyl-CoA

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

What organ absorbs glycogen?

A

The liver

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

What are ketone bodies and what is their function?

A

They are produced by the liver from fatty acids during a low-carbohydrate diet, fasting or too much alcohol. They are alternatives to ATP

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

During ketosis, where will high levels of ketones be present?

A

In the urine and blood but not enough to cause acidosis

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

Why does the brain need a constant supply of ketone bodies and glucose from plasma?

A

There is no glycogen in the brain

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

What does fatty acid synthesis lead to?

A

A fatty acid with an even number of carbons. The process requires ATP

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

What is the structure of a fatty acid?

A

A straight carbon chain with a COOH group

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

What are essential fatty acids?

A

Those that must be in the diet because they can’t be produced

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

What is an ester bond?

A

A glycocidic bond but in fatty acid

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

What 4 types of molecules is cholesterol a precursor for?

A

Bile acids, steroids, hormones and vitamin D

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

What are the sources of cholesterol?

A

From the diet or can be made by the liver

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

When is cholesterol amphipathic?

A

When it’s free

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

When is cholesterol hydrophobic?

A

When its esterified (because there is nothing to interact with water as the OH is gone)

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

When are ketone bodies produced by the body?

A

During fasting (after all fat and glucagon is used up)

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

What are ketone bodies produced from?

A

Acetyl-coA

20
Q

Give 3 examples of ketone bodies

A

Acetoacetate, beta-hydroxybutyrate and acetone (the waste product)

21
Q

Why do unsaturated fatty acids have a lower melting point?

A

They have an irregular structure compared to saturated fatty acids so their intermolecular forces are weaker

22
Q

What type of optical isomerism do most unsaturated fatty acids have? Cis or Trans?

A

Cis

23
Q

Why are trans unsaturated fats bad?

A

They increase levels of LDL

24
Q

What are the 4 pathways of lipid transport?

A
  1. Exogenous pathways - Gut to liver and periphery (muscle and adipose tissue)
  2. Endogenous pathway - Liver to periphery
  3. Recycled pathway - Periphery to liver
  4. In the form of bile acid - Liver to digestive tract
25
Q

Describe the exogenous pathway (from gut to liver and periphery) of lipid transport

A

Lipids from diet are packaged by the small intestine into chylomicrons which are taken up by the liver and periphery

26
Q

What is meant by exogenous?

A

From the outside

27
Q

Describe the endogenous pathway (from liver to periphery) of lipid transport

A

Lipids from the liver are packaged into VLDL and then stored in the periphery

28
Q

What is meant by endogenous?

A

Made by the body

29
Q

Describe the recycling pathways (from periphery to liver) of lipid transport

A

It occurs when the lipid supplies in the liver are being exhausted during starvation or exercise. HDL transports the lipids back to the liver so they can be converted back into energy

30
Q

What are chylomicrins?

A

Molecules that transport triglycerides

31
Q

Describe the bile production pathway of lipid transport

A

Cholesterol is converted into bile acids and released into the cystic duct. Most of the bile acids are reabsorbed by the gut and returned to liver and recycled

32
Q

What is the function of lipoprotein lipase?

A

It metabolises triglycerides into fatty acids and glycerol to remove the triglycerides from VLDL and then moves them across the capillary membrane. This happens because triglycerides cannot go through cell membranes

33
Q

What are apolipoproteins?

A

Proteins in lipoprotein molecules that can hold lipids . They’re amphipathic so it can bind to the protein and to the lipid at the same time

34
Q

How dense is cholesterol compared to tryglycerides and proteins?

A

Between triglycerides and proteins

35
Q

Why are bigger lipoproteins lower in density?

A

Because they are carrying more proteins

36
Q

Why are LDL dangerous?

A

Because they are incorperated into atheromas. In the blood, it’s storage for cholesterol that can’t be stored anywhere else. It’s what is left over once the periphery has absorbed endogenous triglycerides from VLDL from the liver

37
Q

Why is HDL better than LDL?

A

Because HDL lowers cardiovascular risk. It carries lipids from fat cells to the liver when cholesterol is being used up

38
Q

Which type of lipid signifies a risk of atheroma?

A

VLDL

39
Q

What is VLDL used for?

A

Used to transport endogenous cholesterol and triglycerides from the liver to the periphery

40
Q

What is IDL?

A

Intermediate density lipoprotein. It’s the intermediate molecule before VLDL becomes LDL

41
Q

What do the beta cells of the pancreas produce?

A

Insulin

42
Q

What do the alpha cells of the pancreas produce?

A

Glucagon

43
Q

What does hypercholesterolaemia increase the risk of?

A

Arteriosclerosis

44
Q

What is the function of statins?

A

They block endogenous cholesterol synthesis by blocking HMG-CoA Reductase

45
Q

What is simvastatin prescribed for?

A

For cardiovascular disease prophylaxis especially for men over 50

46
Q

What is metabolic syndrome?

A

Its a group of risk factors that increase the risk of cardiovascular disease, stroke and type 2 diabetes

1. Theme 3 (19 decks)

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