Which molecule coats alveolar surfaces and is critical to lung function? renin k

Question

Which molecule coats alveolar surfaces and is critical to lung function?

renin

kinin

surfactant

lecithin

2)

Which of the following is not a function of the respiratory conducting passageways?

humidify air

exchange gases

warm incoming air

allow air to reach the lungs

all of the above are a function of the respiratory conducting pathways

3)

What happens to your diaphragm muscle when you exhale?

it contracts

it relaxes

it does not change

it shortens in length

4)

How does the wall of a vein differ from an artery?

The exterior layer is comprised largely of collagen fibers

It contains smooth muscle

It is lined by a thin layer of endothelium

the middle layer is relatively thin

renin

kinin

surfactant

lecithin

Explanation / Answer

1.

Surfactant is the molecules the coats the surface of alveoli in lungs that reduces surface tension and prevents alveoli collapse. Option 3 is correct.

2.

The respiratory conducting passageways perform functions like purify the air, humidify the air, warm the incoming air and allow the air to reach lungs. Exchange gases is not a function of respiratory conducting passageways. Option 2 is correct.

3.

Diaphragm muscle relaxes during exhalation along with the relaxation of intercoastal muscles. Hence, option 2 is correct.

4.

Veins have three layers: a thin outer layer, a middle layer and a smooth inner layer. The middle layer is relatively thin. Option 4 is correct.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.