Lecture 18

Question 1

breakdown/oxidation of CHO for energy

Answer 1

glycolysis

Question 2

glycolysis

Answer 2

breaks down 2 molecules of pyruvate

- occurs in the cytoplasm

Question 3

stage 1 - glycolysis

Answer 3

• begin with a glucose molecule, an ATP molecule is sacraficed and its phosphate tail (Pi) is donated to glucose
• this process changes glucose into glucose 6-phosphate

Question 4

stage 3 - glycolysis

Answer 4

• Another ATP is sacraficed and the phosphate tail is donated to fructose 6-phosphate = fructose 1,6 diphosphate

Question 5

phosphofructoskinase

Answer 5

• step 3 of glycolysis
• rate limiting enzyme
• assists in controlling the speed of glycolysis
• if energy is needed quickly then PFK will increase or decrease the rate of glycolysis

Question 6

stage 2 - glycolysis

Answer 6

Glucose 6-phosphate converts to fructose 1,6 diphosphate

Question 7

Stage 5 - glycolysis

Answer 7

fructose 1,6-diphosphate splits into TWO molecules of
2,3-phosphoglyceralderhyde

Question 8

stage 6 - glycolysis

Answer 8

At step 6, pairs of H atoms are stripped from each molecule and carried away in a ‘taxi’ (co-enzyme called NAD+)
(limited number of NAD)

Question 9

Steps 7 & 10

Answer 9

a total of 4 ATP molecules are created

at stage 10: two molecules of phosphoenolpyruvate are changed to two molecules of pyruvate

Question 10

how does exercise intensity affect

Answer 10

Slow to mod exercise - pyruvate continues to Stage 2 of CHO breakdown
if exercise intesnity is high - pyruvate is converted to lactic acid and DOES NOT
continue to Stage 2

Question 11

when exercise intensity is high what happens to glycolysis

Answer 11

• PFk increases the rate of glycolysis
• not enough NAD to pick up all H atoms at step 6
• the standed H travel down to step 10 and join with pyruvate = lactic acid is formed

Question 12

lactic acid dissaociates to

Answer 12

lactic acid will split to form H + lactate

• H causes pH to fall (acidic conditions)
• this will cause fatigue and limit peformance

Question 13

is lactic a waste product

Answer 13

• lactic acid can be used as a fuel for energy
• when intensity slows down H is removed from lactic acid
• H atoms are then picked up by NAD and then taken to another pathway where they will assist in making ATP

Question 14

gluconeogenesis

Answer 14

• lacate can be transported to the liver and converted to glucose

Question 15

anaerobic glycolysis and performance

Answer 15

• due to genetics ad to training some individuals have anaerobic glycolsysi energy systems that work faster and more effciently than others
• this makes individuals better atheltes in events (100m swim, 200 & 400m sprint)