Chapter 7: Respiration in humans ( parts of the respiratory system)

Question 1

What are the parts in the humans respiratory system?

Answer 1

1. nasal passages
2. pharynx
3. larynx
4. trachea
   parts in lungs:
5. bronchi
6. bronchioles
7. alveoli

Question 2

Why does the wall of the nostrils bear a fringe of hair and is lined with a moist mucous membrane?

Answer 2

To trap dust and foreign particles.

Question 3

What are the parts of the c-shaped rings of cartilage at the trachea and bronchus?

Answer 3

1. connective tissue surrounding
2. c-shaped ring connected by
3. ligament
4. thin epithelium as the inner wall of the trachea and bronchus

Question 4

What are the cells in the epithelium, the inner wall of the trachea and bronchus?

Answer 4

Gland cells and ciliated cells

Question 5

What do gland cells do?

Answer 5

They secrete mucus to trap dust particles and microorganisms in the air that we inhale

Question 6

What do ciliated cells do?

Answer 6

They have cilia on their surfaces, which beat rhythmically and sweep mucus and dirt up to be coughed up or swallowed

Question 7

What is the function of the alveoli?

Answer 7

It is the site of gas exchange

Question 8

What are the parts in alveoli?

Answer 8

Pulmonary artery ( o2 blood from heart to alveoli), pulmonary vein ( co2 blood from alveoli to heart)

Question 9

What are some factors that affect the rate of diffusion?

Answer 9

• surface area
• diffusion distance
• concentration gradient

Question 10

What is the rate of diffusion in relation to surface area in the lungs?

Answer 10

There is a large surface area with millions of alveoli in each lung.

Question 11

What is the rate of diffusion in relation to the diffusion distance in the alveolar wall?

Answer 11

Short diffusion distance due to a one cell thick alveolar wall, which allows a higher rate of diffusion of gases between the alveolus and blood capillary

Question 12

What is the rate of diffusion in relation to the concentration gradient of the alveoli?

Answer 12

There are numerous blood capillaries surrounding the alveoli, which allows continuous flow of blood to maintain the concentration gradient for diffusion of gases.

Question 13

Why is there a thin film of moisture on the inner layer of the alveolus?

Answer 13

To allow oxygen to dissolve and diffuse across the alveolar wall easily

Question 14

What happens when oxygen is exchanged from the alveolus into the bloodstream?

Answer 14

Oxygen dissolves into the thin film of moisture which then diffuses into the capillaries.

Question 15

What happens when carbon dioxide is exchanged from the bloodstream into the alveolus?

Answer 15

Carbon dioxide diffuses into the alveolus from the blood capillary by diffusion.