21-2: Respiratory Organs (pt 2)

Question 1

What is the function of the alveoli?

Answer 1

sites of gas exchange between inhaled air and blood of pulmonary capillaries

Question 2

respiratory membrane

Answer 2

thin membrane which gasses must cross to get from the air sacs into the blood

Question 3

The walls of the alveoli are made of ___. Each alveolus is surrounded by a ___, made of ___.

Answer 3

simple squamos epithelium (type I cells); extensive capillary bed; simple squamos epithelium

Question 4

Gas exchange occurs quickly by ____.

Answer 4

diffusion (O2 moves alveolus > blood; CO2 moves blood > alveolus)

Question 5

What cells secrete surfactant?

Answer 5

type II cells

Question 6

surfactant

Answer 6

phospholipid secreted by type II cells in alveolar walls; form a coat on gas-esposed alveolar surfaces preventing them from collapsing and sticking together when exhaling

Question 7

alveolar macrophages

Answer 7

highly phagocytic cells that crawl along internal alveolar surfaces removing dust, debris, and microbes, keeping alveoli sterile

Question 8

lungs

Answer 8

pair of cone shaped organs occuping all of the thoracic cavity except the mediastinum

Question 9

apex

Answer 9

superior tip of lung just deep to clavicle

Question 10

base

Answer 10

inferor surface of lung resting on diaphragm

Question 11

hilum

Answer 11

indentation on the medial surface of each lung, where bronchus and pulmonary blood vessels enter

Question 12

Which lung is smaller?

Answer 12

left lung is smaller than right because of the heart’s orientation

Question 13

What are the lobes of the left lung?

Answer 13

superior and inferior

Question 14

What are the lobes of the right lung?

Answer 14

superior, middle, and inferior

Question 15

The lungs are made primarily of ___.

Answer 15

elastic connective tissue, making them soft, spongy and elastic organs

Question 16

pleura

Answer 16

thin double layered membrane that encloses and protects each lung

Question 17

parietal pleura

Answer 17

outer layer lining the thoracic wall (touching the rib cage)

Question 18

visceral pleura

Answer 18

inner layer covering external lung surfaces

Question 19

pleural cavity

Answer 19

tiny space between the 2 layers filled with a lubricating fluid that prevents friction between the membranes during breating

Question 20

pleurisy

Answer 20

inflammation of the pleural membrane that causes painful friction and stabbing pain with each breath

Question 21

pneumothorax

Answer 21

presence of air in the pleural cavity, as from a gunshot wound or stabbing

Question 22

atelectasis

Answer 22

collapsed lung