Biochemistry Flashcards
For metabolism of triglycerides: Where does fatty acid synthesis and activation occur?
In the cytoplasm
How is a dietary fatty acid activated
Addition of a acyl- CoA to form fatty acyl CoA
What must be added to a fatty acyl-CoA for it to enter the mitochondira?
acyl- carnitine group
Where does beta oxidation occur?
In the mitochondia
WHat is the only percursor for fatty acid synthesis?
Malonyl CoA which is formed from acetyl CoA which is formed from citrate in the TCA cycle
What is the main storage form of lipids in the human body?
Triglycerides
Can lipids contain other organic molecules?
Yes, carbohydrates- glycolipid
Prtein- apoprotein
Phosphate- phospholipid
Can fatty acids be used for gluconeogeenisis?
No
What is the first step of fat metabolism?
Lipolysis
Where does beta oxidation occur?
The mitochondrial matrix
How many steps in the beta oxidation cycle?
4 steps in each cycle
What are the products of each beta oxidation cycle?
1 acetyl-CoA
1 FADH2
1NADH + H+
1 fatty acyl-CoA shortened by 2 carbon atoms
How often does beta oxidation happen for the breakdown of a C16 fatty acid?
(16/2) - 1 = 7 times
Where are ketone bodies formed?
Liver mitochondria under fasting conditions
How are ketone bodies formed?
Fatty acids are oxidised by beta oxidation to form acetyl-Co A which is used to form ketone bodies
Where are ketone bodies found after they have been produced?
Diffuse into the blood stream and peripheral tissue. Important for energy metabolism in the brain, heart muscle and renal cortex during starvation.
What happens to ketone bodies in peripheral tissue during starvation?
Converted back into acetyl-CoA which enters the TCA cycle to produce energy
Why are ketone bodies important for maintaining neurological signals?
The can be used to produce glutamine- a neurotransmitter- form alpha ketogluterate
What are the 3 ketone bodies
Acetoacetate
Acetone
Alpha-3-hydroxy-butyrate
What are the 2 functions of ketones?
Energy production and neurotransmitter synthesis
Are ketone bodies water soluble?
Yes
What can accumulate as a byproduct of beta oxidation under conditions of extreme starvation?
Ketone bodies
What is fatty acid synthesis?
The process which drives lipogenesis
Where does fatty acid synthesis occur?
Mainly in the liver