cardio-respiratory and vasuclar systems: respiratory system

Question 1

label the respiratory stystem

Answer 1

Question 2

define inspiration

Answer 2

breathing in

Question 3

define expiration

Answer 3

breathing out

Question 4

define alveoli

Answer 4

tiny air sacs in the lungs that allow gaseous exchange

Question 5

define gas exchange

Answer 5

the process of diffusion of gas from an area of high concentration to an area of low concentration

Question 6

define haemoglobin

Answer 6

red pigment that is attracted to oxygen in a red blood cell

Question 7

describe how gas exchange takes place

Answer 7

• 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.

Question 8

explain how the alveoli are adaped for gas exchange

Answer 8

• 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