Transport Of Gases Flashcards
Esophagus
- muscular layer for food
- it squeezes food and pushes it
Purpose of respiratory system
To provide an efficient means of supplying body with oxygen and remove CO2
Trachea
Open tube made up of rings of cartilage (same as nose and ear)
- acts as a tube, air moving up and down because of changing pressure
- produces mucus that traps bacteria and dust inhaled
Nasal Cavity
Filters, moistens and warms the air which enters the pharynx
What does trachea and bronchi have in them
They have ciliated cells (small hairs) that sweep and trap bacteria and dust back up to the pharynx where it is swallowed
Alveoli
Provide a large SA for gas exchange to occur
1cell thick
Diaphragm
Essential in providing a negative pressure in the lung, so air can enter
Order of transports systems in body
Mouth, trachea, bronchi, bronchioles, alveoli, diaphragm
Lung ventilation requires
A suction pump system
How does lung ventilation work
Changes the pressure of air and volume of lungs
Inhalation
The diaphragm expands the lungs when breathing in
- thus increasing its volume
- lower density
- lower air pressure
Exhalation
- diaphragm rekaxes and decreases lung volume
- ## high density
Features of gas exchange surfaces
- large SA:V
- moist (gases dissolve in water and diffuse across membranes
- thin and permeable
- high concentration gradient on one side of the membrane
Alveoli function and structure
- Large SA:V
- diffusion barrier to gas exchange is very thin
- rich supply of blood vessels
- contains lots of gas for transfers
What prevents the alveoli from collapsing
1 air remains in the aveoli even after breathing out
2 a surfactant is present in the thin layer of fluid over the alveolar surface
