respiration

Question 1

LUNGS:

List the adaptations of the alveoli that make it ideal for gas exchange

Answer 1

Single layer of epithelium cells
Stretch as breathe in
Spring back as breathe out
Huge SA
Moist
Rich blood supply

Question 2

LUNGS:

What prevents the trachea from collapsing?

Answer 2

Rings of cartilage

Question 3

LUNGS:

What happens to the intercostals as we breathe in

Answer 3

External contract

Internal relax

Question 4

LUNGS:

What happens to the rib cage and the diaphragm before we inhale

Answer 4

Ribs - move up and out

Diaphragm - contracts and moves down

Question 5

LUNGS:

What happens to the volume and pressure of the thorax before we inhale air

Answer 5

Volume increases

Pressure decreases

Question 6

LUNGS:

What is the ‘tidal volume’?

Answer 6

The volume of air we breath in and out at rest (typically about 0.5dm3)

Question 7

LUNGS:
List the events of

a) Intercostal Muscles
b) ribs
c) Diaphragm
When we exhale

Answer 7

a) Internal contract, external relax
b) Ribs move down and in

c) Diaphragm relaxes, domes up

Question 8

Describe how we breathe IN

Answer 8

Diaphragm contracts
External intercostal muscles contract

Volume increases and pressure decreases in thorax
Air moves into lungs

Question 9

Describe how we breathe OUT

Answer 9

Diaphragm relaxes
Internal intercostal muscles contract

Volume decreases and pressure increases in thorax
Air moves out of the lungs

Question 10

describe the pathway of an oxygen molecule from alveolus to blood

Answer 10

crosses the single cell alveolar epithelium and then epithelium of the capillary

Question 11

describe ONE feature of the alveolus that allows efficient gas exchange

Answer 11

ONE CELL thick therefore creating a SHORTER diffusion pathway