cardio-respiratory and vasuclar systems: respiratory system Flashcards
1
Q
label the respiratory stystem
A
2
Q
define inspiration
A
breathing in
3
Q
define expiration
A
breathing out
4
Q
define alveoli
A
tiny air sacs in the lungs that allow gaseous exchange
5
Q
define gas exchange
A
the process of diffusion of gas from an area of high concentration to an area of low concentration
6
Q
define haemoglobin
A
red pigment that is attracted to oxygen in a red blood cell
7
Q
describe how gas exchange takes place
A
- the concentration of oxygen ishigher in the alveoli compared to the blood in passing capillaries
- oxygen moves from a high concentration to a low concentration down a conentration gradient
- and enters the bloodstream, attaching to haemoglobin in the red blood cells to form oxyghaemoglobin
- the oxyghaemoglobin travels to the heart and is pumped around the body.
8
Q
explain how the alveoli are adaped for gas exchange
A
- large in number allowing a large surface for diffusion
- the alveoli walls are one cell thick allowing gas exchange to take place
- capillaries provide a constant blood supply for diffusion
- the capillaries touch the alveoli walls, allowing a short diffusion pathway