Metabolism III - Week 1

Question 1

Increased fat intake without expenditure leads to…

Answer 1

Increase in number of adipocytes & adipose within adipocytes (Obesity)

Question 2

Control of energy balance depends on…

Answer 2

Genetics, food abundance, choices or limitations

Question 3

Which fatty acids cannot be made within the body?

Answer 3

Polyunsaturated fatty acids

Question 4

Deficiencies of polyunsaturated fatty acids can lead to…

Answer 4

Membrane disorders, increased skin permeability and mitochondrial disorders

Question 5

Which vitamins are dependent on the uptake of fat?

Answer 5

Vitamins A, D, E and K

Question 6

What is meant by simple lipids?

Answer 6

Fatty acids, triglycerides, waxes

Question 7

What is meant by compound lipids?

Answer 7

Have other associated groups: Phospho-, glyco- lipids, lipoprotein

Question 8

Name 2 steroids.

Answer 8

Steroid hormones, cholesterol

Question 9

Are lipids soluble or insoluble in water?

Answer 9

Insoluble

Question 10

What is the main energy storage form in adipose tissue?

Answer 10

Triglycerides

Question 11

Fatty acids can be….

Answer 11

Saturated. unsaturated or polyunsaturated

Question 12

Polyunsaturated fatty acids tend to be in which configuration?

Answer 12

Cis

Question 13

What is the most common fatty acids in the body?

Answer 13

Palmitic acid, stearic acid and oleic acid

Question 14

Give an example of an essential fatty acid.

Answer 14

Linoleic acid

Question 15

Plant fats tend to be … at room temp

Answer 15

Liquid

Question 16

Animal fats tend to be … at room temp

Answer 16

Solid

Question 17

What are the main products of fat digestion?

Answer 17

Glycerol, fatty acids & monoglycerides

Question 18

Short and medium length fatty acids enter…

Answer 18

portal circulation

Question 19

What happens to longer fatty acids during digestion?

Answer 19

Re-synthesised as triglycerides and re-packaged as chlyomicrons & sent to lymph system then blood stream

Question 20

What is the fate of free fatty acids?

Answer 20

Resynthesised to triglycerides or oxidised to provide energy

Question 21

The breakdown of lipids is called…

Answer 21

Lipolysis

Question 22

How are fatty acids oxidised?

Answer 22

Linking to CoA in the cytoplasm (uses 2ATP)

Question 23

Fatty acid + CoA –>

Answer 23

Acyl-CoA

Question 24

What is the difference between Acyl-CoA and Acetyl-CoA?

Answer 24

Acetyl-CoA contains 2 carbons but Acyl-CoA could contain any amount

Question 25

Which mechanism occurs between the mitochondrial matrix and inter-membrane space?

Answer 25

Carnitine shuttle

Question 26

What is meant by beta-oxidation?

Answer 26

Cycle of reactions which takes acyl-CoA and in 4 steps, shortens it by 2 carbons, producing 1 Acetyl-CoA and new Acyl-CoA

Question 27

How many times is the beta-oxidation cycle repeated?

Answer 27

8 times

Question 28

Oxidation of some fatty acids requires different enzymes. Name these.

Answer 28

Unsaturates, odd-chain, branched chain

Question 29

What happens to glycerol in the breakdown of fats?

Answer 29

Converted to glcyerol-3-phosphate & inserted into metabolism

Question 30

What are ketone bodies?

Answer 30

Bodies of ketones produced from Acteyl-CoA from beta oxidation in the liver

Question 31

Give an example of a ketone body.

Answer 31

Acetone

Question 32

What happens during starvation/gluconeogenesis?

Answer 32

Oxaloacetate consumed for gluconeogenesis. Fatty acids oxidised to provide energy. Large amounts of Acteyl-CoA used so converted to ketone bodies resulting in ketosis or ketoacidosis.

Question 33

In ketoacidosis, which organ primarily stops working?

Answer 33

CNS