Respiratory Anatomy And Physiology

Question 1

What are the key differences between an infant and adult diaphragm?

Answer 1

The amount of type 1 fibers. The adult diaphragm has 50% type 1 fibres and a term infant has half, a pre term infant has half again. The less you have the more you fatigue.

Question 2

What are the 3 different types of pressure gradients?

Answer 2

Atmospheric-pressure exerted by the gases surrounding the body
Intrapulmonary-amount I’d pressure within the alveoli
Intrapleural-amount of pressure in the pleural space

Question 3

What happens with pressure gradients during breathing?

Answer 3

Before inspiration: intrapulmonary pressure is equal
During inspiration: as the lungs increase in volume when inspiratory muscles contract, intra alveolar pressure decreases, establishing a pressure gradient that favors flow INTO the lungs
During expiration: as the lungs recoil passively on relaxation of inspiratory muscles, intra alveolar pressure increases, establishing a pressure gradient that favors flow out of the lungs

Question 4

What is Boyle’s law?

Answer 4

A relationship between the pressure and volume of gases. With a fixed quantity of gas, an increase in volume will result in a decrease in pressure, while a decrease in volume will result in increased pressure.

Question 5

How does elastic recoil help the lungs?

Answer 5

It helps with with expiration by reducing the intrapulmonary volume and therefore increase intrapulmonary pressure relative to atmospheric pressure.

Question 6

What are the 2 clusters of neurons in the medulla that contribute to respiration?

Answer 6

Dorsal respiratory group: mostly inspiratory muscles
-when they fire=inspiration
-when they cease=expiration
Ventral respiratory group: inspiratory and expiratory
-inactive during normal breathing
-enables more forceful inspiration And expiration when demands are high

Question 7

Where are the chemoreceptors located?

Answer 7

Central- the medulla, near respiratory center

Peripheral- in the carotid arteries and aortic arch

Question 8

What stimulates the central chemoreceptors?

Answer 8

Carbon dioxide, it diffuses easily across the BBB.

Question 9

What stimulates the peripheral chemoreceptors?

Answer 9

A decrease in PH acting as a mechanism for compensation.