β-oxidation of fatty acids

Question 1

True or False, The only dietary nutrient in excess that can be converted to fatty acids are Carbohydrates.

Answer 1

False

Question 2

Where does fatty acid synthesis take place

Answer 2

Liver, lactating mammary glands, and to a lesser extent adipose tissue

Question 3

How is the mitochondrial Acetyl CoA produced, in the de novo fatty acid synthesis, produced

Answer 3

oxidation of pyruvate

catabolism of fatty acids, ketone bodies, certain amino acids

Question 4

What is the first step in the de novo fatty acid synthesis

Answer 4

transfer of acetate units from mitochondrial acetyl CoA to the cytosol

Question 5

How does acetyl get into the mitochondrial cytosol

Answer 5

Translocation of citrate produced by the condensation of oxaloacetate (OAA) and acetyl CoA, where acetyl is attached to the citrate

Question 6

Where is the energy for the carbon-to-carbon condensations in fatty acid synthesis supplied from

Answer 6

Carboxylation and then decarboxylation of acetyl groups in the cytosol

Question 7

In the presence of which hormones are Acetyl CoA Carboxylase inactivated through its phosphorylation

Answer 7

glucagon, epinephrine

Question 8

In the presence of which hormones are Acetyl CoA activated by dephosphorylation

Answer 8

insulin

Question 9

What is the major pathway for the catabolism of fatty acids

Answer 9

mitochondrial pathway called β-oxidation

Question 10

What are the main products of β-oxidation

Answer 10

Acetyl CoA, NADH, FADH2

Question 11

What is the name of the enzyme that converts long fatty acid chains into its CoA derivative (Fatty Acyl CoA)

Answer 11

long-chain fatty acyl CoA synthetase (thiokinase)

Question 12

What is the name of the specialized carrier that transports the long-chain acyl group from the cytosol into the mitochondrial matrix

Answer 12

Carnitine

Question 13

What is the name of the rate-limiting transport pro- cess

Answer 13

carnitine shuttle

Question 14

Where is the long-chain fatty acyl CoA synthetase located

Answer 14

outer mitochondrial membrane

Question 15

The conversion of Fatty acid chains and CoA to Fatty Acyl CoA due to energy given off from the conversion ATP to AMP is considered what type of reaction?

Answer 15

Coupled Reaction

Question 16

What enzyme is used in the transfer of the Acyl group from Fatty Acyl CoA to Carnitine

Answer 16

Carnitine Palmitoyltransferase 1

Carnitine Acyl Transferase 1

Question 17

What products are produced in the transfer of the Acyl group from Fatty Acyl CoA to Carnitine using Carnitine Acyl Transferase 1

Answer 17

CoA + Fatty Acyl Carnitine

Question 18

What is transported into the mito- chondrial matrix in exchange for free carnitine by carnitine–acylcarnitine translocase.

Answer 18

Acylcarnitine

Question 19

What enzyme is used in the inner mitochondrial membrane that catalyzes the transfer of the acyl group from Fatty Acyl carnitine to CoA in the mitochondrial matrix, thus regenerating the free carnitine

Answer 19

Carnitine palmitoyltrans- ferase II (CPT-II, or CAT-II)

Carnitine Acyl Transferase 2

Question 20

Carnitine is found mainly in what type of products

Answer 20

Meat

Question 21

What type of muscle contains majority of the body’s carnitine

Answer 21

Skeletal

Question 22

Carnitine can be synthesised from the amino acids lysine and methionine by the enzymatic pathway found in which two organs

Answer 22

Kidney and Liver

Question 23

Two ways in which Carnitine is formed in the body

Answer 23

Uptake of carnitine provided by endogenous synthesis or the diet

Question 24

What are the two stages in β-oxidation of fatty acids.

Answer 24

1st: Removal of successive 2 Carbon units
2nd: Acetyl CoA oxidised to CO2 + H20

Question 25

What type of reaction first starts the β- oxidation process in the matrix of the mitochondria

Answer 25

Dehydrogenation

Question 26

What compound first starts the β- oxidation process in the matrix of the mitochondria

Answer 26

β-Carbon (3), α-Carbon (2)- Fatty Acyl CoA

Question 27

Which enzyme facilitates the production of Enoyl CoA (2 trans), from Fatty Acyl CoA

Answer 27

Acyl CoA Dehydrogenases

Question 28

What oxidising agent facilitates the production of Enoyl CoA (2 trans), from Fatty Acyl CoA

Answer 28

Fad+ to FADH2

Question 29

What reaction is involved in the second step of the β- oxidation process

Answer 29

Hydration

Question 30

What compound starts the 2nd step in the β- oxidation process

Answer 30

Enoyl CoA (2 trans)

Question 31

What is the end product when H20 is added to Enoyl CoA (2 trans)

Answer 31

3-Hydroxyacyl CoA

Question 32

What enzyme facilitates the hydration reaction in the second step

Answer 32

Enoyl CoA hydratase

Question 33

What enzyme facilitates the production of 3-Ketoacyl CoA from 3-hydroxyacyl CoA

Answer 33

3-Hydroxyacyl CoA dehydrogenase

Question 34

What oxidising agent facilitates the production of 3-Ketoacyl CoA from 3-hydroxyacyl CoA

Answer 34

Nad+

Question 35

What type of reaction is the 3rd step in β- oxidation process

Answer 35

Dehydrogenation

Question 36

What compound starts the 4th step in the β- oxidation process

Answer 36

3-Ketoacyl CoA

Question 37

What enzyme is used in the 4th step in the β- oxidation process

Answer 37

β-Ketoacyl-CoA thiolase

Question 38

What compound is involved in the synthesis of fatty acyl CoA and Acetyl CoA in the final step of the β-oxidation of fatty acyl CoA

Answer 38

CoA

Question 39

What drug interrupt the active transport metabolic pathway

Answer 39

Amytal

Question 40

At what level is CO2 released

Answer 40

Citric Acid Cycle

Question 41

At what level is H2O released

Answer 41

Electron transfer chain

Question 42

Differences between fatty acid synthesis and β-oxidation

Answer 42

Fatty acid synthesis occurs in the cytosol while β-oxidation occurs in mitochondria Fatty acid synthase is the only enzyme involved in fatty acid synthesis while in β-oxidation many enzymes are involved NAD is the oxidising agent in β-oxidation while NADP is the oxidising agent in fatty acid synthesis

Question 43

The synthesis of what compound has similar pathways as β-oxidation of fatty acyl CoA

Answer 43

Cholesterol synthesis

Question 44

What is one of the main compound involved in the electron transport chain

Answer 44

Ubiquitine