Respiration Physiology Part 2

Question 1

What drives the ventilation cycle?

Answer 1

Movement of the thoracic wall by skeletal muscles.

Question 2

What is pulmonary ventilation?

Answer 2

the
exchange of air
between the
atmosphere and the
lungs.

Question 4

What are the main phases of pulmonary ventilation?

Answer 4

Inspiration and Expiration.

Question 5

What is primary force?

Answer 5

Respiratory movement

Question 6

What muscles are inspiratory muscles?

Answer 6

diaphragm

external intercostal muscle

Question 7

What muscles are Expiratory muscles?

Answer 7

internal intercostal muscle
abdominal muscle

Question 8

What muscles are Auxiliary inspiratory muscles?

Answer 8

• scalenes, sternocleidomastoid

Question 9

What is Inspiration subdivided into?

Answer 9

Normal quiet breathing

Thoracic breathing:

Question 10

What is the difference between normal quiet breathing and thoracic breathing ?

Answer 10

Normal quiet breathing (abdominal breathing ): movement of diaphragm
• Thoracic breathing: movement of external intercostal muscles

Question 11

Describe the process of Inspiration

Answer 11

Contraction of the diaphragm lengthens the chest cavity, pulls down the lungs
• Causes the lung volume to increase
• Causes the decrease of intrapulmonary pressure
Flow of air into the lungs
Always an active process

Question 12

Describe the process of expiration

Answer 12

Expiration is mainly caused by
• elastic recoil of the diaphragm
• relaxation of the external intercostal muscles
• relax diaphragm up and move ribs together
• Typically a passive process

Question 13

What is forced breathing also known as?

Answer 13

Deep breathing

Question 14

What inspiratory muscles can also help to expand the thoracic cavity?

Answer 14

sternocleidomastoid muscles
• pectoralis minor muscles

Question 15

• what Other expiratory muscles can help with forced expiration?

Answer 15

Abdominal recti
> Internal intercostals

Question 16

What is intrapulmonary pressure?

Answer 16

The pressure of air inside the lung alveoli

Question 17

Air travels from?

Answer 17

regions of high air pressure to regions of low air pressure

Question 18

When does air enter the lungs in terms of pressure?

Answer 18

When alveolar pressure (Pₐₗᵥ) is less than atmospheric pressure (Pₐₜₘ).

Question 19

When does air exit the lungs in terms of pressure?

Answer 19

When alveolar pressure (Pₐₗᵥ) is greater than atmospheric pressure (Pₐₜₘ).

Question 20

What is the formula for airflow (F)?

Answer 20

F = (Pₐₗᵥ - Pₐₜₘ) / R (resistance).

Question 21

What causes airflow in the lungs?

Answer 21

The difference between intrapulmonary pressure and atmospheric pressure.

Question 22

What is the difference between intrapulmonary pressure and atmospheric pressure called?

Answer 22

Direct Force

Question 23

What causes changes in alveolar pressure?

Answer 23

Changes in the dimensions of the chest wall and lungs.

Question 24

What is intrapleural pressure?

Answer 24

A: The pressure within the pleural cavity, which is always slightly negative than atmospheric pressure (around -5 mmHg or -5 to -7.5 cmH₂O). It is always negative.

Question 25

Define transpulmonary pressure (Ptp).

Answer 25

Ptp=alveolar pressure (P alv)- intrapleural pressure (Pip)

Question 26

What is the function of the ranspulmonary pressure (Ptp)?

Answer 26

holds the lungs open.

Question 27

What happens during inspiration?

Answer 27

Diaphragm and intercostal muscles contract • Thoracic cavity volume increases • Intrapleural pressure becomes more negative • Lungs expand • Intrapulmonary pressure becomes negative • Air flows into the lungs

Question 29

What happens during expiration?

Answer 29

A: • Muscles relax • Thoracic volume decreases • Intrapleural pressure becomes less negative • Lungs recoil • Intrapulmonary pressure rises above atmospheric pressure • Air flows out of the lungs

Question 31

What is the pressure difference across the chest wall?

Answer 31

P(atm) - P(ip) = 5 mmHg; this balances the chest wall’s tendency to move outward.

Question 32

What is pleural pressure equal to?

Answer 32

Interpleural pressure, which is alveolar pressure minus elastic recoil pressure.

Question 33

What is the diagnosis of a 14-year-old boy, tall and thin, chest tightness after 1000 meters?

Answer 33

Pneumothorax

Question 34

What is pneumothorax?

Answer 34

Air escapes from the lungs or leaks through the chest wall into the pleural cavity, causing lung collapse.

Question 35

What is the role of pleural pressure?

Answer 35

• Keeps the lungs inflated • Promotes the return of venous blood and lymph

Question 36

What are the key forces in pulmonary ventilation?

Answer 36

• Primary force: Respiratory muscle movement • Direct force: Pressure differences