Lipids + Beta Oxidation

Question 1

what are the functions of lipids?

Answer 1

1. energy “store–> can be oxidized to acetyl CoA, NADH and FADH2
2. bile acids (hydrophobic and hydrophilic portions)
3. formation of steroid hormones
4. form prostaglandins
5. cell membranes

Question 2

how are lipids released and carried in times of fasting?

Answer 2

fatty acids stored in adipose are cleaved by lipases, carried on albumin to needy cells

Question 3

what are the 2 destinations of the formed Acetyl CoA from beta oxidation?

Answer 3

fed into the Kreb’s cycle or converted to ketone bodies in the liver

Question 4

what is necessary to “activate” fatty acids delivered to a cell before they can be oxidized to acetyl CoA? does this require energy?

Answer 4

activation to acyl CoA by acyl CoA synthetase (thiokinase)

**requires ATP input!

Question 5

basics of beta oxidation

Answer 5

1. acyl CoA cleaved into two carbon units (Acetyl CoA)

2. process repeated until all carbons have been cleaved

Question 6

if a fatty acid is not EVEN chained, how does beta oxidation work?

Answer 6

works normally until you reach last 5 carbon chain… enzyme THIOLASE cleaves to 2 carbon acetyl CoA + 3 carbon propionyl CoA–> succinylcholine CoA (intermediate in Kreb’s cycle)