Respiratory System

Question 1

What are the functions of the respiratory system during exercise?

Answer 1

Breathe air into lungs
Transfer O2, through process of diffusion, from lungs to blood
Transfer CO2 & other gases from blood, via diffusion, into lungs to be breathed out

Question 2

Describe how air goes through body

Answer 2

1. Nose, nasal cavity & mouth warm, filter & moisten incoming air
2. Travels through throat to trachea. This branches into 2 bronchi
3. Air travels to bronchioles, lined with cilia
4. Air travels to alveolar sacs, containing alveoli
5. Diffusion occurs, O2 & CO2 move between alveoli & RBCs

Question 3

What happens to the respiratory system during inspiration?

Answer 3

External intercostal muscles contract gently, pulling ribs up & out
Diaphragm contracts, pulling itself down
Volume of chest cavity goes up
Air pressure drops - gas moves from high to low

Question 4

What happens to the respiratory system during expiration?

Answer 4

External intercostal muscles & diaphragm relax
Ribs go back down & diaphragm moves up
Pushes CO2 out of lungs into air

Question 5

What happens to the respiratory system during exercise?

Answer 5

External intercostal muscles contract gently, pulling ribs up & out
Diaphragm contracts, pulling itself down
Volume of chest cavity goes down
Air pressure drops - gases move from high to low

Question 6

Explain the process of diffusion in alveoli

Answer 6

Gasses diffuse down a concentration gradient from an area of high concentration to low
Oxygen diffuses from alveoli into capillaries to even out concentration
After breathing in, alveoli have high concentration of O2, blood capillaries have low concentration

Question 7

What is vital capacity?

Answer 7

The max amount of air you can breathe out after max inspiration

Question 8

What is tidal volume?

Answer 8

Volume of air breathed in & out for normal breath

Question 9

What is minute ventilation? How do we calculate it?

Answer 9

Amount of air breathed in & out in 1 minute

MV = Tidal volume x frequency of breaths/min (ME= TV x freq)

Question 10

What are the short term responses to exercise?

Answer 10

1. Respiratory system detects increased levels of CO2
2. Nervous impulses received by internal, external intercostal muscles & diaphragm
3. Increased rate of breathing & increased volume of thoracic cavity
4. You breathe faster & deeper

Question 11

What are the long term benefits of exercise on the respiratory system?

Answer 11

Respiratory muscles become stronger 
Surface area for gaseous exchange increase
VC & ME improve, so more O2 
Increase capillary network 
More O2 in RBCs & more O2 expired