tissues of the gaseous exchange system

Question 1

what are bronchioles comprised of

Answer 1

-larger bronchioles may have cartilage
-walls comprised mostly of smooth muscle and elastic fibres
-contain columnar epithelial cells

Question 2

what are trachea and bronchi comprised of

Answer 2

-ciliated cell and goblet cell
-both have similar structure but bronchi is narrower
-airways supported by rings of cartilage
-smooth muscle

Question 3

what does cartilage do

Answer 3

-prevent collapse during inspiration due to low pressure
-C shaped ring not complete to allow flexibility and space for food

Question 4

what is the alveoli comprised of

Answer 4

-squamous epithelium
-surrounded by blood capillaries
-contain elastic fibres
-thin walls

Question 5

what does the elastic fibre in the alveoli do

Answer 5

stretch during inspiration and recoil during expiration

Question 6

what is the role of the smooth muscle

Answer 6

-smooth muscle contracts narrowing lumen and constricting airway
-recoil during relaxation, returning to original shape and size after contraction deforms elastic fibres

Question 7

what happens to smooth muscle during relaxation

Answer 7

during relaxation smooth muscle is elongated by elastic fibres

Question 8

what happens when smooth muscle relaxes

Answer 8

the airway is dilated again

Question 9

what’s the role of elastic fibres

Answer 9

-recoil after contraction
-elongate smooth muscle during relaxation

Question 10

what do the airways need to be effective

Answer 10

-large enough to allow sufficient air flow without obstruction
-supported to prevent collapse when low air pressure inside created by inspiration
-flexible for movement

Question 11

where is elastic tissue found

Answer 11

-in the lung tissue
-in the bronchiole
-in the alveoli

Question 12

where are goblet cells and ciliated cells found

Answer 12

-in trachea and bronchi

Question 13

where is smooth muscle found

Answer 13

-in the bronchiole
-in the bronchi
-in the trachea

Question 14

where is cartilage found

Answer 14

-in the trachea
-in larger bronchi

Question 15

when is it useful for smooth muscle to contract and constrict the airway, narrowing the lumen

Answer 15

-in the presence of harmful substances
-cannot be voluntarily controlled
-can be caused by an allergic reaction

Question 16

how do goblet cells and ciliated epithelium work together

Answer 16

-airways lined by ciliated epithelium
-goblet cells in epithelium release mucus to trap pathogens
-cilia move mucus to top of airway to be swallowed so stomach acid can kill