Breathing Process

Question 1

What is the major function of the respiratory system?

Answer 1

To supply the body with oxygen and to dispose of carbon dioxide.

Question 2

What do you understand by pulmonary ventilation?

Answer 2

It is the act of breathing, which can be described as the movement of air into and out of the lungs.

Question 3

What are the major mechanisms that drive pulmonary ventilation?

Answer 3

Atmospheric pressure(Patm)

Alveolar pressure(Palv)

Intrapleural pressure(Pip)

Question 4

What is alveolar pressure?

Answer 4

Air pressure within the alveoli.

Question 5

What is intrapleural pressure?

Answer 5

The pressure of air within the pleural cavity, between the visceral and parietal pleurae.

Question 6

The ability to breath is __________ on the air pressure of the ___________ and the air pressure within the _______.

Answer 6

dependent; atmosphere; lungs

Question 7

What are the 3 types of pressure that pulmonary ventilation is dependent on?

Answer 7

• Atmospheric pressure
• Intra-alveolar pressure
• Interpleural pressure

Question 8

What is atmospheric pressure?

Answer 8

It is the amount of force that is exerted by gases in the air surrounding any given surface such as the body.

Note:- Atmospheric pressure can be expressed in terms of the unit atmosphere abbreviated atm or in millimetres of mercury(mm Hg).
-One atm= 760 mm Hg(atmospheric pressure at sea level).

Question 9

What is intra-alveolar pressure?

Answer 9

It is the pressure of air within the alveoli which changes during the different phases of breathing.

Question 10

What causes the parietal pleura and visceral pleura to adhere to one another?

Answer 10

A thin layer of serous fluid.

Question 11

Intrapleural pressure is always lower than or negative to the ____________ pressure.

Answer 11

intra-alveolar

Question 12

Which cells closely monitor the intrapleural pressure?

Answer 12

Mesothelial cells

Question 13

What is transpulmonary pressure?

Answer 13

It is the difference between the intrapleural and intra-alveolar pressures and it determines the size of the lungs.

Note: A higher transpulmonary pressure corresponds to a larger lung.

Question 14

What are the physical factors affecting pulmonary ventilation?

Answer 14

Surface tension of the Alveolar fluid.

Compliance of the lungs.

Airway resistance

Question 15

What do you understand by thoracic wall compliance?

Answer 15

It is the ability of the thoracic wall to stretch under pressure.

Question 16

What is pulmonary ventilation?

Answer 16

It is a mechanical process that depends on volume changes in the thoracic cavity.

Question 17

Pulmonary ventilation comprises of two major steps: __________ and __________.

Answer 17

inspiration ; expiration

Question 18

Explain the inspiration process?

Answer 18

It is a process that causes air to enter the lungs.

Question 19

Explain the expiration process?

Answer 19

It is a process that causes air to leave the lungs.

Question 20

What can be considered as a respiratory cycle?

Answer 20

One sequence of inspiration and expiration.

Question 21

What are the two muscle groups that are used during normal respiration?

Answer 21

Diaphragm and external intercostal muscles.

Question 22

What happens when the diaphragm contracts?

Answer 22

It moves inferiorly toward the abdominal cavity, creating a larger thoracic cavity and more space for the lungs.

Question 23

What happens when the external intercostal muscles contracts?

Answer 23

The ribs are going to move upward and outward, causing the rib cage to expand which increases the volume of the thoracic cavity.

Question 24

Why is it said that the process of normal respiration is passive?

Answer 24

It means that energy is not required to push air out of the lungs.

Question 25

Give the different types of breathing?

Answer 25

• Quiet breathing(Eupnoea)
• A deep breath(Diaphragmatic breathing)
• A shallow breath(Costal breathing)
• Forced breathing(hyperpnea)

Question 26

Describe eupnoea(quiet breathing)?

Answer 26

It is a mode of breathing that occurs at rest and does not require the cognitive thought of the individual.

Question 27

Describe hyperpnea(forced breathing)?

Answer 27

It is a mode of breathing that can occur during exercise or actions that require the active manipulation of breathing. (e.g Singing)