MEH ENERGY STORAGE

Question 1

where does fatty acid synthesis occur?

requires?

Answer 1

the cytoplasm

NADPH

Question 2

effect of glucagon on fa synthesis?

Answer 2

inhibits

Question 3

Which effect would the hormone insulin have on the enzyme hormone sensitive lipase?

Answer 3

Decrease in activity

Question 4

signs and symptoms would you expect to see in a baby with Von Gierke’s Disease?

Answer 4

protuberant abdomen (hepatomegaly)
> glycogen is deposited but can't be fully broken down so remains in liver.

Sweating and pallor relieved by feeding
> due to hypoglycaemia, as glycogen cannot be broken down into glucose to raise blood glucose levels.

High blood fatty acid levels
>body performs gluconeogenesis to compensate for the low blood glucose.

Question 5

when are fatty acids synthesised?

Answer 5

when there is a high blood glucose level and high insulin levels.

Question 6

Why are fatty acids synthesised in body cells when blood glucose levels are high?

Answer 6

The glucose has undergone glycolysis to form acetyl CoA, but the body cell doesn’t need this so it’s converted to fatty acids as a means of storage

insulin has acted on all cells to inc their glucose uptake but not all cells need this energy so XS glucose stored as fatty acids instead

Question 7

what is malonyl co A used for?

Answer 7

fa synthesis

Question 8

list the products that can be synthesised from acetyl-coA

Answer 8

fatty acids
sugars
alcohol
aa
- immediate in lipid biosynthesis

Question 9

what is the pathway of TAG to glycerol?

activated/stimulated by?

Answer 9

TAG –> fatty acids + glycerol

\+
adrenaline
glucagon
growth hormone
cortisol
thyroxine

-
insulin

Question 10

what are the major energy stores in a 70kg man? used when?

Answer 10

Glycogen
>during the overnight fast,
>response to stress and exercise.

Triacylglycerols
> starvation, 
> response to stress, 
> third trimester of pregnancy, 
> lactation 
> prolonged aerobic exercise (marathon running).

muscle Protein
> only in emergency starvation.

Question 11

compare and contrast TAGs and glycogen as energy stores

Answer 11

TAG

• major store
• stored in adipose tissue
• efficient energy storage > hydrophobic and stored anhydrously
• more reduced so contains more energy per carbon atom

Glycogen

• stored in liver/muscle
• polar and stored with water