78 - Nutritional Value of Carbohydrates

Question 1

Product of glucose that is converted to fat

Answer 1

Pyruvate

Question 2

Anomer of glucose that is in starch and glycogen

Answer 2

Alpha-D-glucopyranose

Question 3

Antique name for glucose

Answer 3

Dextrose

Question 4

GLUT in liver

Answer 4

GLUT2

Question 5

GLUT that is insulin-sensitive

Answer 5

GLUT4 in skeletal muscle

Question 6

Only organs with the ability to release free glucose from glycogen

Answer 6

Liver and kidney (have glucose-6-phosphatase)

Question 7

Pathways stimulated by insulin in a cell

Answer 7

Growth pathway (cell proliferation, counters apoptosis)
Metabolic pathway (glycogen synthesis, protein synthesis, NOS formation, antilipolysis)

Question 8

Size of glycogen molecules

Answer 8

Can have up to 55,000 glucose units in a glycogen molecule

Question 9

Osmotic action of glycogen

Answer 9

A single glycogen molecule is osmotically equivalent to a single glucose (so doesn’t make the liver swell).

Question 10

Pompe’s disease

Answer 10

Lysosomes engorge with glycogen due to a lack of a-1,4-glucosidase.

Respiratory failure causes death, usually before age 2.

Question 11

Example of a glycogen storage disease

Answer 11

Pompe’s disease

Question 12

Stimuli that lead to breakdown of glycogen

Answer 12

Stress (EG adrenaline) or fasting (EG glucagon)

Question 13

Universal cellular stress signal

Answer 13

cAMP

Question 14

How is cellulose digested?

Answer 14

By bacteria in gut. Humans don’t make enzymes to break down cellulose.

Question 15

Part of cereals that provide most energy

Answer 15

Endosperm contains starch and proteins

Question 16

When does a person exhale large amounts of hydrogen gas?

Answer 16

When gut bacteria metabolise dietary sugars due to pancreatic insufficiency, lactose intolerance or coeliac disease

Question 17

How does sugar result in tooth cavities?

Answer 17

Sugar is metabolised to acetic, propionic and butyric acids by bacteria in dental plaques. Teeth (calcium phosphate) dissolve at pH of ~5.5.

Question 18

Two diseases of low dietary fibre

Answer 18

Haemorrhoids

Diverticulosis

Question 19

Effect of fibre on gut microflora

Answer 19

Promotes growth of protective microbes

Question 20

Glycaemic index

Answer 20

% response of blood glucose elevation relative to 50grams of glucose (EG: 100% means that food elevates blood glucose as much as pure glucose)