exercise

Question 1

why do you respire more when you exercise?

Answer 1

Muscles need energy from respiration to contract. When you exercise, some muscles contract more frequently than normal. so you need more energy which comes from increased respiration.

Question 2

what does an increase in respiration mean?

Answer 2

your cells need to get more oxygen in them

Question 3

what happens to your breathing rate, heart rate and breath volume?

Answer 3

all increase

Question 4

why does you body respire anaerobically?

Answer 4

when you do vigorous exercise and your body can’t supply oxygen to your muscles quickly enough

Question 5

what are the effects of long periods of exercise?

Answer 5

it causes muscle fatigue so your muscles stop contracting efficiently

Question 6

what does anaerobic respiration lead to?

Answer 6

an oxygen debt when you stop exercising

Question 7

oxygen debt

Answer 7

the amount of extra oxygen your body needs to react with the build up of lactic acid to remove it from the cells and convert it to glucose

Question 8

what are the products when oxygen reacts with lactic acid?

Answer 8

carbon dioxide and water

Question 9

why do you have to keep breathing hard for a while after you stop exercising?

Answer 9

to get more oxygen into your blood, this is then is transported to the muscle cells that didn’t get the oxygen in time when you were exercising

Question 10

what happens to your pulse and breathing rate after exercise?

Answer 10

it will stay high while there are high levels of lactic acid and carbon dioxide

Question 11

where is lactic acid transported after exercise?

Answer 11

to the liver via the blood

Question 12

what is lactic acid converted to in the liver?

Answer 12

glucose, then to glycogen so glycogen levels in the liver and muscles can be restored

Question 13

how can you investigate the effect of exercise on the body?

Answer 13

1. measure your breathing rate and heart rate for 1 minute after sitting down for 5 minutes
2. repeat after 5 minutes of walking, then 5 minutes of jogging, and then 5 minutes of running
3. compare your results on a bar chart

Question 14

what happens to your pulse rate depending on the type of exercise?

Answer 14

the more intense the exercise is, the higher your pulse rate will increase as your body needs to get more oxygen to the muscles, and take more carbon dioxide away from the muscles

Question 15

why can anaerobic respiration lead to muscle fatigue?

Answer 15

lactic acid builds up in muscles, preventing efficient contraction

Question 16

how do muscles store glucose?

Answer 16

as glycogen

Question 17

what changes take place when muscular activity increases in the body and why?

Answer 17

-heart rate increases and arteries dilate: increases flow of oxygenated blood to muscles
-breathing rate and depth increase: increases rate of gaseous exchange, get more oxygen in the blood
-stored glycogen is converted back to glucose

Question 18

how is lactic acid transported away from the muscles?

Answer 18

blood flow through the muscles transports lactic acid to the liver where it is oxidised back to glucose