Respiration: Mechanics Flashcards
What are the values for Partial pressure of oxygen & CO2 at rest?
PO2 = 100 mmHg PCO2 = 40 mmHg
a higher PCO2 means more acidic blood
What is the function of upper airways?
Humidify, warm and filter the air
Why is humidifying the air important?
Breathing dry air will result in the tracheas epithelial layer to wear away over time
Why is filtering the air important and how does the body do it?
Traps and prevents foreign particles & microbes from entering the respiratory system
Resp tract lined by pseudo-stratified ciliated columnar epithelium. The cilia trap particles/microbes, and stuck to mucus which travels towards mouth and expelled
What is quiet breathing?
relaxed breathing, often at rest
Inspiration is an ACTIVE process contracting the diaphragm
Expiration is PASSIVE and elastic recoil of the muscle is used to return to norm.
What is strenuous breathing?
Greater contraction of diaphragm (inspiration ACTIVE).
Expiration is ALSO ACTIVE as air needs to be forced out allowing more air to enter to supply the oxygen demand
What are some muscles of INSPIRATION?
- Sternocleidomastoid
- External intercostals
- Diaphragm (MAJOR ONE)
others are more involved strenuous breathing
What are some muscles of EXPIRATION?
- Internal intercostals
- Abdominal muscles (rectus, transverse abdominis & internal/external obliques)
What is efficiency for low and high intensity breathing?
Low level = very efficient, small muscle effort
High intensity = less efficient, turbulent gas flow & more muscles used (fatiguing)
What is functional residual capacity (FRC)?
The VOLUME OF AIR in the LUNG at the END OF EXPIRATION - during quiet breathing
What is tidal volume?
Volume of breath coming into lungs EACH BREATH
Why are lung/respiratory diseases bad?
Negatively affect mechanical properties of the lung reducing efficiency of gas exchange
