Ventilation of the Lungs Flashcards
1
Q
Describe the process of inspiration.
A
- External intercostal muscles contract
- Thoracic cage moves up and out and diaphragm flattens
- Plural pressure becomes more negative
- Lungs inflate
- Alveolar pressure becomes lower than atmospheric pressure and hence air moves into the lungs
2
Q
Is inhalation an active or passive process?
A
Active
3
Q
Is quiet expiration an active or passive process?
A
Passive
4
Q
TRUE OR FALSE:
Intrapleural pressure, at all phases of inspiration and expiration, is less than atmospheric pressure.
A
True
5
Q
What muscles are involved in forced expiration?
A
- Abdominal muscles (External oblique, internal oblique, rectus abdominus)
- Internal intercostal muscles
6
Q
What muscles are involved in forced inspiration?
A
- Diaphragm
- External intercostal muscles
- Sternocleidomastoid
- Scalene
- Serratus anterior
- Pec major
7
Q
Give examples of when forced expiration occurs.
A
- Exercise
- Resp obstruction i.e. coughing
- Diseased states such as emphysema
8
Q
Give examples of situations when quiet breathing becomes effort do to the diaphragm not easily being able to move into the abdomen.
A
- Pregnancy
- Obesity
- Corsets
