the respiratory system

Question 1

What is in the air that a person breathes in?

Answer 1

It is high in oxygen and nitrogen, but low in carbon dioxide

Question 2

What happens to the shape and size of the chest cavity as a person breathes out?

Answer 2

• the diaphragm becomes a dome shape again as it relaxes and moves upwards
• the intercostal muscles contract which brings down the ribs and sternum, making the chest cavity smaller
• this increases the pressure inside the chest cavity and causes air to be forced out of the lungs

Question 3

What is in the air that a person breathes out? Why is it so?

Answer 3

It is high in nitrogen and carbon dioxide as the full process of gaseous exchange has taken place

Question 4

By how much does a person’s breathing increase when they are exercising?

Answer 4

It increase greatly, and it can increase by up to three times the rate as when a person is at rest

Question 5

What is aerobic respiration?

Answer 5

Respiration that occurs in the presence of oxygen

Question 6

What is the equation for aerobic respiration?

Answer 6

glucose + oxygen —> carbon dioxide + water (+ energy)

Question 7

When is aerobic respiration used by the body?

Answer 7

When the body continues an activity for a long period of time

Question 8

What is needed in order for the aerobic system to work efficiently?

Answer 8

There has to be a constant supply of oxygen for the body

Question 9

What are some examples of when aerobic respiration is used by an athlete?

Answer 9

• marathon
• cross-country run
• kickboxing
• 100 meter swimming race

Question 10

What is anaerobic respiration?

Answer 10

Respiration that occurs in the absence of oxygen

Question 11

What is the equation for anaerobic respiration?

Answer 11

glucose —> energy (+ lactic acid)

Question 12

When is anaerobic respiration used by the body?

Answer 12

When the body works without sufficient oxygen being supplied to the muscles

Question 13

Why can anaerobic respiration only be used in short bursts?

Answer 13

Because oxygen is not being used to generate the energy

Question 14

What is oxygen debt?

Answer 14

The result of the muscles respiring anaerobically during vigorous exercise

Question 15

Why is there such a thing as oxygen debt?

Answer 15

Because as a person’s body runs out of a sufficient supply of oxygen, they call on the glycogen stores in the body as an alternative energy supply

Question 16

How long can people respire anaerobically for?

Answer 16

The maximum is approximately 60 seconds

Question 17

What happens during anaerobic respiration?

Answer 17

Effectively the body is ‘borrowing’ oxygen, which is then ‘owed’ to the body (oxygen debt)

Question 18

What does anaerobic respiration cause to happen in the body?

Answer 18

There will be a build up of lactic acid in the muscles, which will make the muscles hurt

Question 19

What is one of the main reasons for completing a cool down after exercise?

Answer 19

To enable the lactic acid to disperse and avoid any discomfort

Question 20

What are some examples of when anaerobic respiration is used by an athlete?

Answer 20

• 100 meter sprint
• weight lifting
• basketball
• HIIT

Question 21

What happens in the recovery period?

Answer 21

Straight after any vigorous exercise a person has to take in extra oxygen, which helps to convert the possibly painful presence of lactic acid in simple waste products that have to be removed from the body

Question 22

What are the three types of simple waste products that have to be removed from the body during the recovery period?

Answer 22

• expiration of breath
• perspiration
• excretion through urine and faeces

Question 23

What does the expiration of breath do?

Answer 23

Removes the carbon dioxide and other waste products from the lungs

Question 24

What is perspiration?

Answer 24

A form of temperature control

Question 25

What does perspiration do for the body?

Answer 25

It removes excess water, such as sweat, at the same time that it is letting heat escape through evaporation from the skin

Question 26

What must heat be released from the body?

Answer 26

To prevent the body from overheating

Question 27

What does excretion through urine and faeces do for the body?

Answer 27

Removed excess water and the other waste products from the lactic acid

Question 28

What is the role of the blood?

Answer 28

• controls body temperature

* transports oxygen, glucose and waste products around the body

Question 29

What happens to the shape and size of the chest cavity as a person breathes in?

Answer 29

• the diaphragm changes from a dome shape as it flattens and moves downwards
• the intercostal muscles raise the ribs up and push out the sternum, making the chest cavity larger
• this reduces the pressure inside the chest cavity and causes air to be sucked into the lungs