Respiration and Gas Exchange Flashcards
What happens to the diaphragm when inspiring (inhaling)?
It contracts, moves down and flattens
What happens to the intercostal muscles when inspiring?
They contract.
What happens to the ribs when inspiring?
They move up and out
What happens to the volume and pressure of the thorax when inspiring?
Volume increases, pressure decreases
What happens to the diaphragm when expiring (exhaling)
It relaxes and goes back to its dome position.
What happens to the intercostal muscles when expiring
They relax.
What happens to the ribs when expiring?
They move down and inward
What happens to the volume and pressure of the thorax when expiring
Volume decreases, pressure increases
What is the tube that is that connects the throat to the bronchi called?
The trachea.
What are the 2 tubes connecting the windpipe to the lungs called?
Bronchus (single), Bronchi (plural)
What are the airways that branch from the bronchi called and what is their function?
Bronchioles. Their function is to carry oxygen rich air into the lungs, and carbon dioxide rich air out.
What are the tiny air sacs on the bronchioles called and what are they used for?
Alveolus (s), Alveoli (p). They are where gas exchange happens.
How does gas exchange happen?
The alveoli are surrounded by capillaries, where carbon dioxide rich blood is transported to the alveoli, which take out the carbon dioxide and replace it with oxygen, and the blood leaving is oxygenated. The now carbon dioxide reach air is exhaled.
What are 3 ways the alveoli have adapted for gas exchange?
- Their walls are very thin, allowing the gases to aid diffusion (gas from higher concentrated area moving to lower concentrated area)
- They are moist, again aiding diffusion.
- they have a large surface area.
