3.1.3 The Mammalian Gas Exchange System

Question 1

CArtilage

Answer 1

• C shaped Rings in trachea
• Strong and flexible
• Keep trachea open
• Flexible so we can move and flex as we breathe
• In bronchi, but not C shape
• Bronchioles do not contain cartilage
• Bronchioles do not contain goblet cells, but contain ciliated epithelium
• Bronchioles contain elastic fibres and smooth muscle that adjust the size of the airway to increase or decrease airflow

Question 2

Smooth muscle

Answer 2

• Involuntary
• Helps regulate flow of air into lungs
• Walls of bronchi and bronchioles
• Dilates and constricts regulating flow of air

Question 3

Elastic fibres

Answer 3

• Let alveoli stretch with air
• Recoil so expiration requires no energy or contractions

Question 4

Goblet cells

Answer 4

• In trachea in epithelial cells
• Produce mucus
• Traps dust, bacteria and microbes, prevents them from reaching lungs
• Mucus swept along by cilia up to mouth where it is swallowed

Question 5

Bronchi

Answer 5

Cartilage does no form a C shape but can form full rings

Question 6

Bronchioles

Answer 6

no cartilage, cilkiated epithelium but nio goblet cells

larger ones have elastic fibres and smooth muscle that regulate volume of air uptaken