2.4 the lungs and adaptions of the small intestine

Question 1

what are the goblet cells in the lungs?

Answer 1

• release/secrete mucus
• cilia cells use their appendages to trap debris/bacteria back up to mouth and nose to be removed

Question 2

why does the trachea have rings of muscle?

Answer 2

• prevent tube from collapsing
• keep airways open
  -maintain flexibility

Question 3

what are adaptions of the alveoli and why?

Answer 3

• one-cell thick increase rate of diffusion
• large surface area increase rate of diffusion
• good blood supply obtain as much oxygen from bloodstream as possible

Question 4

what are adaptions of the small intestine?
- vili?
- blood supply?
- one-cell thick?
- long?

Answer 4

• vili increase surface area, vili are covered in microvilli increasing surface area even further
• large blood supply rapidly removes products of digestion, increasing concentration gradient
• one cell thick - short diffusion pathway
• long - large surface area