Lipid Metabolism (Refer Book Too)

Question 1

Which organs are the most active for producing triacylglycerol

Answer 1

Liver and intestine

Question 2

What are the two main biosynthetic pathway for lipid synthesis and where are they occur

Answer 2

SN glycerol 3 phosphate pathway - Liver and Adipose tissue
Monoacylglycerol pathway - Intestine

Question 3

What are the hormones that influence conversion of free fatty acids and glycerol

Answer 3

Epinephrine, norepinephrine and glucagon

Question 4

What is the enzyme that break triacylglycerol molecule

Answer 4

TAG lipase

Question 5

Where does biosynthesis of fatty acid occur

Answer 5

Cytosol in animal and yeast
Chloroplast stroma in plants

Question 6

Inhibitor of acetyl CoA carboxylase

Answer 6

Palmitoleoyl CoA, epinephrine, cAMP mediated phosphorylation and glucagon

Question 7

Promoter of acetyl CoA carboxylase

Answer 7

Insulin and citrate

Question 8

FAS1 and FAS2

Answer 8

FAS 1 is of vertebrates and fungi. They have one large polypeptide. Animal has two homodimer, fungi has heterodimer, a (3 subunit) and b (4 subunit)
FAS 2 is of plants and bacteria. They have seven different domain.

Question 9

What is elongation of fatty acid

Answer 9

Adding two carbons on 16 C fatty acid. For eg stearic acid (18 C)
Adds malonyl CoA in ER and acetyl CoA in mitochondria

Question 10

Types of fatty acids oxidation and where does it occur

Answer 10

a oxidation - peroxisome
B oxidation - peroxisome and mitochondria
w oxidation - ER

Question 11

What enzyme activates fatty acid before undergoing mitochondrial oxidation

Answer 11

Acyl CoA ligase

Question 12

Name of the carrier that transport fatty acyl CoA in the mitochondria

Answer 12

Carnitine

Question 13

Upto what chain length can fatty acid cross the mitochondrial membrane

Answer 13

12 C chain length

Question 14

What is the chemical name of carnitine

Answer 14

B hydroxy g trimethyl ammonium butyrate

Question 15

Name the processes of B oxidation of saturated fatty acids even number

Answer 15

Oxidation or dehydrogenation
Hydrolysis
Oxidation or dehydrogenation
Thiolysis

Question 16

How many cycles will a 16 carbon molecule undergoes in b oxidation and how many acetyl CoA will be formed

Answer 16

8 acetyl CoA will be formed and it will undergo 7 cycle

Question 17

How many ATP is produced in 16 carbon b oxidation

Answer 17

106 ATP

Question 18

In case of b oxidation of odd number carbon what is produced

Answer 18

Propionyl CoA is yielded

Question 19

What are the enzyme used in be oxidation of odd number carbon

Answer 19

Propionyl CoA carboxylase
Methylmalonyl epimerase
Methylmalonyl mutase

Question 20

What is produced in case of monounsaturated carbon

Answer 20

Palmitoleoyl CoA

Question 21

What is formed second time in poly unsaturated fatty acids

Answer 21

2,4 dienoyl CoA

Question 22

Enzymes used in poly unsaturated fatty acids

Answer 22

2,4 dienoyl CoA reductase
3,2 Enoyl CoA isomerase

Question 23

What happens in peroxysomal b oxidation

Answer 23

It does not degrade fatty acids it shorten the chain

Question 24

Why does no ATP is formed in peroxisome

Answer 24

Because the fadh2 formed goes to oxygen to form hydrogen peroxide

Question 25

Where does b oxidation of fatty acids take place in plants

Answer 25

Glyoxysome via glyoxylate pathway

Question 26

What does a oxidation does

Answer 26

It is a minor pathway. IT degrades branched fatty acids

Question 27

What does phytanic acid become after oxidation

Answer 27

Pristanic acid

Question 28

Where does phytanic acid come from

Answer 28

It is an oxidation product of phytol of chlorophyll

Question 29

What causes Refsum's disease

Answer 29

If a oxidation is defective and phytanic acid is not degraded

Question 30

What happens in w oxidation

Answer 30

It is a minor pathway. Oxidation of terminal carbon of a normal fatty acid occurs and leads to the synthesis of small amount of dicoboxylic acid.

Question 31

What catalyzes the w oxidation

Answer 31

Cytochrome P 450

Question 32

Whats leads to the formation of ketone bodies

Answer 32

In mitochondria of liver when the acetyl CoA accumulates beyond its capacity to be oxidized it leads to the formation of ketone bodies

Question 33

What are the products of ketogenesis

Answer 33

Acetoacetate, b hydroxybutyrate and acetone

Question 34

What happens in the high concentration of ketone bodies

Answer 34

Ketonemia ketonurea both are called ketosis. Diabetes mellitus hence ketoacidosis