6.6 Structure of the human gas exchange system

Question 1

Order of organs humans use to breathe

Answer 1

Nose, trachea, bronchi, bronchioles, alevoli

Question 2

Why do humans require an efficient gas exchange system?

Answer 2

• large vol. of CO2 and O2 need to be exchanged
• have high metabolic rates
• large organisms = large vol. of living cells
• maintain high body temps. (Linked to high metabolic rate and respiratory rate)

Question 3

What’s the trachea?

Answer 3

Flexible air way with muscle lines with ciliated epithelium and goblet cells
supported by rings of cartilage that stop it from collapsing

Question 4

What’s the bronchus?

Answer 4

Divisions of the trachea leading to the lung
Produce mucus that traps particles
Has cilia to move the mucus

Question 5

What are bronchioles?

Answer 5

Branching of the bronchi
Has muscle in walls with epithelial cells
- allows them to constricts and control air flow in alveoli

Question 6

What are alveoli?

Answer 6

Air sacs that stretch and fill with air
Lined with epithelium
There’s collagen and elastic fibres between alveoli
Elastic fibres allow them to stretch and recoil