Bile and Plasma Lipids

Question 1

What is a phospholipid?

Answer 1

A lipid based molecule which has a polar head and hydrophobic trail regions

Question 2

What is glycolysis?

Answer 2

The breakdown of glucose into pyruvate

Question 3

What is gluconeogenesis?

Answer 3

Glucose generation from non-carbohydrate carbon substrates such as pyruvate

Question 4

What is glycogenolysis?

Answer 4

The breakdown of glycogen into glucose

Question 5

What is lipolysis?

Answer 5

The breakdown of lipids, from triglycerides to free fatty acids and glycerol

Question 6

What are ketone bodies?

Answer 6

Type of lipid based energy molecule produced when the body lacks glucose for energy

Question 7

Given the hydrophobicity of fats, how are they transported around the body?

Answer 7

As lipoproteins

Question 8

Lipoproteins are transported via two pathways.. What are they?

Answer 8

Exogenous and Endogenous Pathway

Question 9

The exogenous pathway transports what… from where to where…?

Answer 9

Dietary lipids from the intestine to tissues

Question 10

The endogenous pathway transports what… from where to where…?

Answer 10

Endogenous TGs and cholesterol from the liver to tissues

Question 11

What are names of the four types of Lipoprotein

Answer 11

Chylomicrons
VLDLs
LDLs
HDLs

Question 12

Of the four lipoproteins, which has the largest size?

Answer 12

Chylomicrons

Question 13

Of the four lipoproteins, which has the largest density?

Answer 13

HDLs

Question 14

Of the four lipoproteins, which has the the smallest size?

Answer 14

HDLs

Question 15

Of the VLDLs and HDLs, which has the the smallest density?

Answer 15

VLDLs

Question 16

Of the lipoprotein categories, which has the highest lipid %?

Answer 16

Chylomicrons

Question 17

Of the lipoprotein cateogies, which has the highest protein %?

Answer 17

HDLs

Question 18

What are the four types of Apoproteins?

Answer 18

A, B, C, E

Question 19

What is the function of Apoproteins A, B, C, E?

Answer 19

A: Reverse Cholesterol Transport
B: LDL Binding and clearance
C: Regulation of LPL
E: Remnant receptor binding and clearance

Question 20

LPL is activated by which Apoprotein?

Answer 20

Apoprotein C-II

Question 21

Give 5 examples of things which can alter your LDL:HDL ratios

Answer 21

1. Genetics
2. Poor diet
3. Poor glucose (T2 Diabetes)
4. Lack of exercise
5. Central obesity

Question 22

LPL converts a Chylomicron into…? What is removed?

Answer 22

Chylomicron remnant. Fatty acids and Apo C is removed

Question 23

A chylomicron remnant has which Apoproteins?

Answer 23

E and B

Question 24

A chylomicron remnant is picked up the liver through which Apoproteins and which process?

Answer 24

Apo E and B, receptor mediated uptake

Question 25

The liver packages Chylomicron remnants into...?

Answer 25

VLDLs

Question 26

LPLs act on which two classes of lipoproprotein?

Answer 26

VLDL and Chylomicrons

Question 27

VLDL binds to LPL and becomes...?

Answer 27

IDL

Question 28

IDL binds to... to form an LDL?

Answer 28

Hepatic Lipase

Question 29

LDL binds to the peripheral tissues by which Apoprotein?

Answer 29

Apo B

Question 30

What happens when LDL enters the peripheral tissue?

Answer 30

It is picked up by an endosome and broken by lysosome to release free amino acids and cholesterol. The cholesterol is transformed by cholesteryl ester via LCAT. Remaining produces are packaged into HDL

Question 31

An HDL molecule is picked up by the liver via which apoprotein?

Answer 31

Apoprotein A

Question 32

What are Xanthoma?

Answer 32

Cholesterol deposits

Question 33

What are the normal levels of cholesterol?

Answer 33

< 5.0 mmol/L

Question 34

What is the mechanism of Statins?

Answer 34

Inhibition of HMG-CoA Reductase

Question 35

What are the two classes of adipose tissue?

Answer 35

White adipose tissue and Brown adipose tissue

Question 36

What two ways are White Adipose Tissue synthesised?

Answer 36

1. Endogenously by glucose and driven by insulin | 2. Via breakdown of VLDLs or Chylomicrons via LDLs which release TGs

Question 37

During a starvation event, the glucose levels dissipate in the brain. What happens?

Answer 37

Fats are converted into ketone bodies in the liver (via b-oxidation and ketogenesis)

Question 38

What is the difference about the cells in WAT and BAT?

Answer 38

White adipose tissue: One significant droplet Brown adipose tissue: More droplets and significantly smaller. Has mitochondria and thermogenin channels to generate heat

Question 39

Outline the process of RBC breakdown

Answer 39

1. Haemoglobin is broken down into Heme and Globin 2. Heme is then converted to Biliverdin 3. Biliverdin is converted to Bilirubin 4. Bilirubin binds to Albumin and circulates in the plasma and is picked up by the liver 5. The bilirubin undergoes conjugation with glucaronic acid to make it more soluble 6. It is then excreted as bile into the bile duct and then intestine 7. Once in intestine, can go two ways 7a. Bacteria act on the bile to form urobillinogen to be sent to kidneys for excretion 7b. Or, it can be sent back to the portal circulation