Lower resp tract

Question 1

How much gas is exchanged in the lungs each day?

Answer 1

20m2

Question 2

What is minute ventilation (volume of air inhaled/exhaled per min)?

Answer 2

5 litres/ minute

Question 3

What is cardiac output?

Answer 3

5 litres/ minute

Question 4

What is the extent of the conducting zone?

Answer 4

Trachea –> terminal bronchioles

Question 5

What is the extent of the respiratory zone?

Answer 5

Terminal bronchioles –> alveoli

Question 6

How far does the trachea extend?

Answer 6

From larynx to carina (C6 - T5)

Question 7

Where is the greatest resistance to airflow?

Answer 7

Main airways (trachea and main bronchus)

Question 8

Describe the pathway of air flow from nose to alveolus (11)

Answer 8

1. Nasal cavity
2. Pharynx
3. Larynx
4. Trachea
5. Main bronchus
6. Lobar bronchi
7. Segmental bronchi
8. Terminal bronchioles
9. Respiratory bronchioles
10. Alveolar ducts
11. Alveoli

Question 9

What us an acinus?

Answer 9

The lung tissue supplied with air by one terminal bronchiole

Question 10

What are type 1 pneumocytes?

Answer 10

Pavement cells (one cell thick, flat epithelial cells)

Question 11

What are type 2 pneumocytes?

Answer 11

Cells in alveoli that secrete surfactant

Question 12

What cells make up an alveolus? (3)

Answer 12

Type 1 pneumocytes
Type 2 pneumocytes
Alveolar macrophages

Question 13

How many membranes make up the air-blood barrier?

Answer 13

3; alveolar epithelium, basement membrane, and endothelial cells