intro to the respiratory system

Question 1

what are the components of the respiratory tree?

Answer 1

Upper Respiratory Tract: oro-pharynx and larynx

Lower respiratory tract - conducting airways and respiratory zone (alveoli and terminal bronchioles)

Question 2

how many times is the airway divided?

Answer 2

23 times

Question 3

how many divisions make up the conducting airways?

Answer 3

first 16 divisions

Question 4

how many divisions make up the respiratory zone?

Answer 4

last 7 divisions

Question 5

what type of epithelium is found in the trachea, bronchi and bronchioles?

Answer 5

ciliated pseudo-stratified columnar

Question 6

what controls the diameter of the trachea?

Answer 6

smooth muscle

Question 7

what do the glands of the trachea do?

Answer 7

secrete mucus

Question 8

what is dead space gas?

Answer 8

volume of gas breathed out of the conducting airways before alveolar gas is exhaled

Question 9

what is the epithelium in the upper airways?

Answer 9

thicker pseudostratified columnar epithelium

Question 10

what is the epithelium in the lower airways?

Answer 10

simple epithelium

Question 11

why is all the epithelium of the airways covered in mucus?

Answer 11

to trap dust/microbes

Question 12

what is the mucociliary elevator?

Answer 12

Cilia move mucus upwards towards the throat where it’s swallowed

Question 13

what is the function of the C shaped cartilage?

Answer 13

stiffen the airways and prevent them collapsing

Question 14

how does the cartilage change as the bronchi get bigger?

Answer 14

cartilage rings get thicker

Question 15

what are type 1 alveolar cells and how much of the wall do they make up?

Answer 15

squamous

90%

Question 16

what are type 2 alveolar cells and how much of the wall do they make up?

Answer 16

cuboidal

10%

Question 17

what do type 2 alveolar cells produce and what does it do?

Answer 17

surfactant: reduces the surface tension and stops alveoli from collapsing.

Made up of phospholipoprotein

Question 18

what are pores of Kohn and what is their function?

Answer 18

pores between adjacent alveoli – collateral ventilation between alveoli

Question 19

how do you calculate partial pressure?

Answer 19

total pressure in gas mixture x fractional concentration of gas

Question 20

what social factors affect respiratory disease?

Answer 20

• Poor housing, nutrition and income (eg TB)
• Smoking (COPD and CA-lung)
• Travel (TB, etc.)

Question 21

what environmental factors affect respiratory disease?

Answer 21

• Air pollution, especially particulates and SO2 (COPD/asthma)
• House dust mites (asthma)

Question 22

what occupational factors affect respiratory disease?

Answer 22

• Dust and chemical exposure, and allergies (asbestosis, mesothelioma, silicosis, pneumonconiosis, pulmonary fibrosis, fibrosing alveolitis, etc.)