Mechanics Of Breathing-1 Flashcards
What are the secondary functions of respiration ?
Acid-base balance Vocalisation Defence against pathogens Avenue for water and heat loss Enhancing venous return Activating some. Plasma proteins
What is the primary function of respiration ?
Gas exchange
What is internal respiration ?
Oxygen is essential for ATP production by oxidative phosphorylation
What is external respiration ?
Oxygen uptake and carbon dioxide removal - requires circulatory system as well
What makes up the upper airways ?
Air passages in head and neck
- opening of larynx =glottis- covered by epiglottis to prevent food entering
What makes up the respiratory tract ?
Pharynx to lungs, starting with larynx - it’s held open by cartilage
What are the 2 zones of the respiratory tract ?
Conducting zone- conducts air from larynx to lungs
Respiratory zone- contains sites of gas exchange
Describe the conducting zone
Trachea divide into 2 bronchi which divide into smaller bronchi and bronchioles
Volume is about 150ml
Air is warmed, humidified and filtered
- goblet cells secrete mucus to trap any pathogens
Trachea is surrounded by chapped cartilage to keep it open
How much mucus do you swallow each day?
1L
Describe the respiratory zone
Organised to have maximum surface area and mini is wall thickness
- about 300 million alveoli - total sa 100m squared
- alveolar wall is a single squamous epithelium layer with basement membrane membrane fused - 0.2 micrometers thick
What muscles are used in breathing ?
Diaphragm
Internal/external intercostal muscles
What are the lungs surrounded by ?
A pleura sac with a visceral pleura on the outside and a parietal pleura on the inside surface
Between these 2 pleura is intrapleural space contain 15ml intrapleural fluid
During inspiration is atmospheric or alveolar pressure greater ?
Atmospheric air is greate r
During expiration is atmospheric or alveolar air greater ?
Alveolar
What is normal atmospheric air pressure ?
760mmHg
What is intraalveolar pressure ?
0 at rest
Because it is equal to atmospheric at rest