Lipid metabolism

Question 1

Another name for lipid/fat

Answer 1

Triglycerides

Question 2

Triglyceride is a

Answer 2

3 carbon molecule calleda glycerol attached to three fatty acid tails

Question 3

Where are ketone bodies produced in the body ?

Answer 3

In the liver by ketogenesis from excess acetyl CoA

Question 4

What is Ketosis

Answer 4

metabolic state in which some of the body’s energy supply comes from ketone bodies in the blood

Ketosis will take place when the body needs energy and there is not sufficient glucose available for the body.

Question 5

What product is released from B-Oxidation of fatty acids

Answer 5

Acetyl CoA

Question 6

What is the role of carnitine fatty acid oxidation

Answer 6

Transport the activated FA acyl co A into matrix

Question 7

Fatty acid oxidation can be divided into 3 parts. what are they?

Answer 7

Activation of fatty acids
Transport of FA into mitochondrial matrix
B oxidation of FA

Question 8

Acyl CoA is the important product of and where does it enter

Answer 8

FA activation

Enters B-oxidation

Question 9

Why must Acyl Co A pass through the inner mitochondrial membrane

Answer 9

must reach the matrix where B-oxidation enzymes are located

Question 10

B- oxidation pathway occurs where

Answer 10

Mitochondrial matrix

Question 11

ATP production from FA oxidation gives a Net of

Answer 11

120 ATP

Question 12

Ketogenesis produces

a) Acetoacetate
b) Β-hydroxybutyrate
c) Both of the above examples of ketone bodies, made by ketogenesis

Answer 12

c) Both of the above examples of ketone bodies, made by ketogenesis

Question 13

Ketone bodies can be smelt..

Answer 13

on a person who is fasting (low carb diet)

Question 14

1. Ketosis occurs in the blood In diabetes because

Answer 14

too many ketone bodies are made than can be used by the brain and heart

Question 15

1. Ketosis and ketoacidosis can cause

Answer 15

breathing difficulties and coma

Question 16

The two major products of triacylglycerol digestion in the small intestine are fatty acids and

Answer 16

monoacylglycerols

Question 17

The major function for bile released during the digestion of triacylglycerols is to

Answer 17

act as emulsifier

Question 18

Lipoproteins that transport triacylglycerols from intestinal cells to the bloodstream are called

Answer 18

Chylomicrons

Question 19

. Before a fatty acid can undergo Beta-oxidation, it must be activated and then shuttled across the inner mitochondrial membrane. The activating agent and shuttle molecule are

Answer 19

CoA and carnitine

Question 20

B-oxidation allows for ketogenesis which produces ketone bodies - The starting material for the process of ketogenesis is

Answer 20

acetyl CoA

Question 21

What are micelles and chylomicrons

Answer 21

Free FA and MAGs combine to form small spherical droplets called micelles (smaller than TAGS )

These are then readily absorbed into the intestinal cells - once absorbed they are repackaged into TAGS and packed into chylomicrons which deliver TAGS to the bloodstream

Question 22

1. How are stored fats mobilized for oxidation?

Answer 22

Hormone sensitive lipase hydrolyses the fat releasing free fatty acid and glycerol

Question 23

Where and how are fatty acids activated prior to ß oxidation? How many ATP equivalents are used?

Answer 23

Fatty acids are activated in the cytosol, requires coenzyme A and worth of 2 ATP

Question 24

How are fatty acyl-CoAs transported to the site of ß oxidation? Where is the site of oxidation? What is produced during one cycle of ß oxidation?

Answer 24

Fatty acyl CoA are transported from the intermembrane space into the mitochondrial matrix using Carnitine, releases the fatty acid and goes back into the intermembrane. Oxidation of fatty acid occurs in the matrix