Lipids 2

Question 1

What process does the body use to breakdown FA’s to produce energy?

Answer 1

B-Oxidation

Question 2

Where does b-oxidation occur?

Answer 2

Mitochondrial matrix

Question 3

What does b-oxidation produce?

Answer 3

• Acetyl CoA
• FADH2
• NADH

Question 4

What are the 3 stages of b-oxidation called?

Answer 4

• Activation
• Transport
• Degradation

Question 5

Where are the FA’s activated?

Answer 5

Cytosol

Question 6

Where are the FA’s transported to?

Answer 6

Inner mitochondrial membrane

Question 7

What happens to the FA during activation?

Answer 7

Has a CoA group attached to it

Question 8

What does the attachment of the CoA group produce?

Answer 8

Acyl CoA

Question 9

What replaces the CoA of Acyl CoA to allow it to move into the mitochondrial matrix?

Answer 9

Carnitine

Question 10

How does Acyl CoA enter the outer membrane of the mitochondria?

Answer 10

Can pass freely into it

Question 11

Once inside the outer mitochondrial membrane, what enzyme replaces the CoA with carnitine?

Answer 11

Carnitine Palmytol Transferase 1

Question 12

What transporter does acyl carnitine use to enter the mitochondrial matrix?

Answer 12

• Transferase

Question 13

What happens to the acyl carnitine when it arrives in the matrix?

Answer 13

• Carnitine is removed by carnitine palmytol transferase 2 and CoA is added

Question 14

What happens to the carnitine removed by carnitine palmytol transferase?

Answer 14

It is moved back through another transferase enzyme into the outer membrane

Question 15

What is carnitine palmytol inhibited by to stop synthesis and degradation at the same time?

Answer 15

Malonyl CoA

Question 16

What happens if there is a deficiency of CAT-1?

Answer 16

No b-ox

- Hypoglycaemia

Question 17

How do you treat hypoglycaemia?

Answer 17

• IV glucose

- Consume short chain FA’s

Question 18

Why does consumption of shorter chained FA’s help treat hypoglycaemia?

Answer 18

They can diffuse into the matrix

Question 19

What are the 4 main steps of degredation? And what does each stage produce?

Answer 19

• Dehydrogenation (FADH2)
• Hydration
• Dehydrogenation (NADH)
• Thiolysis (acetyl CoA)

Question 20

What does each cycle of B ox produce?

Answer 20

• 1 acetyl CoA

- FA 2 carbons shorter than the original

Question 21

How much acetyl CoA, NADH and FADH2 does complete b - ox of palmitate produce?

Answer 21

• 7 acetyl CoA
• 8 FADH2
• 8 NADH

Question 22

What is the ATP yield per FADH2?

Answer 22

2

Question 23

What is the ATP yield per NADH?

Answer 23

3

Question 24

What is the ATP yield per acetyl CoA?

Answer 24

12

Question 25

What happens to FA's longer than 22 carbons before B oxidation can occur?

Answer 25

Pre beta oxidation in the peroxisome

Question 26

Why can FA's not be used to produce glucose?

Answer 26

Acetyl CoA back to pyruvate is very unfavourable

Question 27

If there is an excess of acetyl CoA what is it converted to?

Answer 27

Ketone bodies

Question 28

How many acetyl CoA's are used to produce a ketone body?

Answer 28

2

Question 29

Why is the conversion of acetyl CoA to ketone bodies useful?

Answer 29

Some tissues can't use FA's for energy production but can use ketone bodies?

Question 30

What is an important organ that can't utilise FA's for energy?

Answer 30

The brain

Question 31

What happens during uncontrolled diabetes?

Answer 31

- Body starts producing ketones - Ketonemia and academia result - Blood pH drops - COMA AND DEATH