Energy systems in muscle cells

Question 1

During exercise

Answer 1

Breathing rate and volume of each breath increases to bring more o2 and remove co2

heart rate increases, so blood supplies muscles with more o2 quicker and remove co2 quicker

Question 2

If insufficient o2 (rigorous exercise)

Answer 2

heart and lungs unable to supply muscles with sufficient o2.

As a result, muscle cells cannot support ETC, so respire anaerobically. Instead of co2 , water and ATP being produced, pyruvate converts to lactate. - continue to contract but less efficiently

Question 3

Anaerobic conditions in glycolysis

Answer 3

Hydrogen ions transferred from NADH to pyruvate to form lactate

A lot less ATP produced

Question 4

Oxygen debt: long periods of vigorous activity

Answer 4

lactate levels accumulate - oxygen debt

glycogen reserves in muscles become low as more glucose is used for respiration, and additional glucose transported from liver

as body stores of glycogen become low, person suffers from muscle fatigue

Question 5

lactate is taken where after exercise

Answer 5

liver by blood

Question 6

Lactate when taken to liver

Answer 6

oxidised to carbon dioxide and water

converted to pyruvate and glucose, then glycogen - glycogen levels in liver and muscles can be restored

REQUIRES OXYGEN

Question 7

Taking in amount of oxygen required to remove lactate and replace body’s reserves of oxygen is called?

Answer 7

repaying oxygen debt

Question 8

different types of muscle fibres

Answer 8

cardiac muscle

involuntary muscles - internal organs

voluntary muscles

Question 9

skeletal muscle fibres

Answer 9

fast-twitch fibres
slow-twitch fibres

Question 10

Fast-twitch fibres:
speed of contraction
length of contraction
activity
generate atp
mitochondria
blood supply
myoglobin concentration
storage fuel

Answer 10

contract quickly

short periods of time

sprinting

generate ATP by glycolysis only

few mitochondria

low blood supply

myoglobin supply low

storage fuel - glycogen

Question 11

Slow-twitch fibres:
speed of contraction
length of contraction
activity
generate atp
mitochondria
blood supply
myoglobin concentration
storage fuel

Answer 11

slowly
long period
long distance running
aerobic respiration
many mitochondria
large blood supply
high myoglobin concentration
fats is fuel