Nutrition And Glycolysis

Question 1

Living things require energy for…

Answer 1

Biosynthetic work, transport work, mechanical work, electrical work, osmotic work

Question 2

ATP consists of…

Answer 2

Adenine ring, ribose sugar, and three phosphates

Question 3

What is the definition of 1 Kcal? What is 1 Kcal in joules?

Answer 3

The amount of energy required to raise temperature one kilogram of water by one degree celcius.
4.2 Kilojoules

Question 4

How many units do oligosaccharides consist of?

Answer 4

3-12

Question 5

Units in: starch, sucrose, lactose, fructose, maltose, glycogen

Answer 5

Storage molecule in plants, glucose
Glucose - fructose
Glucose - galactose
Monosaccharide
Glucose - glucose
Storage molecule in animals, glucose

Question 6

What are the 9 essential amino acids?

Answer 6

Isoleucine, lysine, threonine, histidine, leucine, methionine, phenylalanine, tryptophan, valine

Question 7

Fat soluble vitamins and their deficiencies

Answer 7

A - Xerophthalmia
D - Rickets
E - Neurological abnormalities
K - Defective blood clotting

Question 8

Water soluble vitamins and their deficiencies (10)

Answer 8

B1 (Thiamin) - Beriberi
B12 - Anaemia
B6 - Dermatitis, Anaemia
Biotin - Alopecia, scaly skin, CNS defects
C - Scurvy
Choline - Liver damage
Folate - Neural tube defects, Anaemia
Niacin - Pellagra
Riboflavin - Ariboflavinosis

Question 9

What is low and high fibre intake associated with?

Answer 9

Low - bowel cancer and constipation

High - reduce cholesterol and risk of diabetes

Question 10

What do RNI, EAR and LRNI stand for?

Answer 10

Reference Nutritional Intake
Estimated Average Requirement
Lower Reference Nutrient Intake

Question 11

What can low protein intake lead to?

Answer 11

Can result in insufficient blood protein synthesis leading to a decreases in plasma oncotic pressure and oedema (as seen in the disease Kwashiorkor)

Question 12

Glycolysis enzymes and what they catalyse

Answer 12

Hexokinase (glucokinase in liver) - phosphorylates 6 carbon sugars

Phosphofructokinase-1 - conversion of fructose-6-phosphate to fructose-1,6-bisphosphate and ATP to ADP

Pyruvate kinase - phosphoenulpyruvate to pyruvate and ATP

Question 13

Why does glucose get phosphorylated?

Answer 13

Make glucose negatively charged
Prevents passage back across plasma membrane
Increases reactivity of glucose for subsequent steps

Question 14

Committing step

Answer 14

Step 3 in phase 1 of glycolysis, fructose-6-phosphate to fructose-1,6-bisphosphate

Question 15

Allosteric and hormonal regulation of phosphofructokinase(PFK)

Answer 15

Allosteric - muscle, inhibited by high ATP, stimulated by high AMP
Hormonal - liver, inhibited by glucagon, stimulated by insulin

Question 16

Hexokinase inhibited by…

Answer 16

Glucose-6-phosphate

Question 17

Pyruvate kinase stimulated and inhibited by…

Answer 17

High insulin:glucagon ratio

Question 18

Important intermediates in glycolysis

Answer 18

1,3-bisphosphoglycerate(haematology), dihydroxyacetone-P(production of fat)

Question 19

Which reaction does lactate dehydrogenase catalyse? And where does the lactate go?

Answer 19

NADH + H+ + pyruvate -> NAD+ + lactate
Used in red blood cells, skeletal muscles in anaerobic respiration.
Heart or liver(gluconeogenesis)

Question 20

Hyperlactaemia and Lactic Acidosis lactate concentration thresholds

Answer 20

Normal - <1mM
Hyperlactaemia - 2-5mM
Lactic Acidosis - above 5mM

Question 21

Essential fructosuria

Answer 21

Fructokinase missing, fructose in urine no clinical signs

Question 22

Fructose intolerance

Answer 22

Aldolase missing, fructose-1-P accumulates in liver, leads to liver damage, treatment - remove fructose from diet

Question 23

Metabolic pathways that glucose can enter

Answer 23

Glycolysis, pentose phosphate, glycogen synthesis