Metabolism - Lecture Thirty-Five

Question 1

Why do we need food stores?

Answer 1

The body cannot store ATP, therefore fuel to make ATP must be stored instead

Question 2

Fat storage

Answer 2

Triacylglycerols that are stored as fat droplets in adipose tissue. Excess fat and carbohydrate from diet can be converted to stored fat as we have unlimited fat stores

Question 3

Tri-acyl-glycerol

Answer 3

Three-fatty acids-glycerol

Question 4

Double bond in a triacylglycerol

Answer 4

You get a kink in the fatty lipid chain. The kinking affects the fluidity of the phospholipid membranes

Question 5

Synthesis of triacylglycerols

Answer 5

Stimulated by insulin

Question 6

Synthesis of triacylglycerols - Fatty acids from

Answer 6

Chylomicrons

Question 7

Synthesis of triacylglycerols - Glycerol backbone from

Answer 7

Glucose

Question 8

Synthesis of triacylglycerols - Activation of fatty acids to

Answer 8

acyl-CoA

Question 9

Where does the glycerol phosphate come from?

Answer 9

From glycolytic pathway

Question 10

Mobilisation of triacylglycerols

Answer 10

Hydrolysis of TAGs catalysed by hormone-sensitive lipase

Question 11

What is the mobilisation of triacylglycerols stimulated by?

Answer 11

Hormones: adrenaline and glucagon

Question 12

What does mobilisation of triacylglycerols release?

Answer 12

Free fatty acids and glycerol

Question 13

Glycogen

Answer 13

Branched polysaccharide, α, 1-4 and α, 1-6 glycosidic bonds

Question 14

Where is glycogen stored?

Answer 14

Liver and muscle

Question 15

Where are glycogen granules?

Answer 15

Cytoplasm

Question 16

Glycogen synthesis

Answer 16

Occurs mainly in liver and muscle immediately after a meal and requires energy inputs (ATP and UTP)

Question 17

What stimulates glycogen synthesis?

Answer 17

Insulin

Question 18

Mobilisation of glycogen

Answer 18

Degraded by glycogenolysis

Question 19

Liver glycogen

Answer 19

Released as glucose into blood

Question 20

Muscle glycogen

Answer 20

Releases fuel for glycolysis within muscle cells

Question 21

Excess glucose carbon is converted to fatty acids

Answer 21

This occurs in the liver and is a complex and energy-requiring process.
Fatty acids are exported as TAGs in VLDL and stored as TAGs in adipose tissue

Question 22

What stimulates excess glucose carbon converting to fatty acids

Answer 22

Insulin

Question 23

Fuel for brain

Answer 23

Glucose (cannot use fatty acids)

Question 24

Fuel for red blood cells

Answer 24

Glucose

Question 25

Fuel for liver

Answer 25

Mostly fatty acids

Question 26

Fuel for heart

Answer 26

Mostly fatty acids

Question 27

Fuel for resting muscle

Answer 27

Mostly fatty acids

Question 28

Fuel for muscles during a marathon

Answer 28

Mix of fatty acids and glucose