Gaseous exchange in animals

Question 1

What do alveoli do?

Answer 1

They provide a large surface area for gaseous exchange in the lungs

Question 2

Where are they found and why there?

Answer 2

Deep inside the body to retain necessary moisture for exchange

Question 3

What do alveoli secrete and why?

Answer 3

Surfacant to break surface tension

Question 4

Describe the two vital cells for exchange

Answer 4

Simple squamous epithelium in the alveoli

Simple squamous endothelium in the capillaries

Question 5

Describe the respiratory tree?

Answer 5

Trachea 
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Bronchiole ---------Bronchus---------Bronchiole 
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Alveolar ducts 
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Alveoli

Question 6

How does inspiration work?

Answer 6

• Breathing in
• External intercostal muscles contract
• internal intercostal muscles relax
• Ribs pulled upwards and outwards
• Diaphragm flattens (contracts)

Question 7

How does expiration work?

Answer 7

• Breathing out
• external intercostal muscles relax
• internal intercostal muscles contract
• ribs pulled inwards and downwards
• Diaphragm curves (relaxes)