Repsiratory System Flashcards
What is the diaphragm?
A sheet of muscle that separates the chest cavity from the rest of the body
Where are the intercoastal muscles found? What do they do?
Between the ribs and they control rib movement
What happens to the diaphragm during inspiration?
It contracts and moves downwards
What happens to the intercoastal muscles during inspiration?
They contract and move the ribs upwards and outwards
Why do the diaphragm and intercoastal muscles do what they do during inspiration?
To increase the size of the chest and decrease the air pressure inside it which sucks air into the lungs
What can the pectoral muscles and the sternoid mastoid do to help inspiration?
Lift the ribs up and out even further than the diaphragm and intercoastal muscles to
What happens to the diaphragm during expiration?
It relaxes and moves back to its domed shape
What happens to the intercoastal muscles during expiration?
The intercoastal muscles relax
Why do the intercoastal muscles and diaphragm do what they do during expiration?
The decrease the size of the chest and increase the air pressure in the chest so air is forced out the lungs
What do the abdominal muscles do during expiration?
They perform a passive process of relaxation which pulls the ribs downwards and inwards even further
What happens during Gaseous exchange?
The alveoli are surrounded by capillaries, oxygen and carbon dioxide diffuse between the air and the alveoli and the blood in the capillaries
What is diffusion?
Movement of gas from an area of high concentration to an area of low concentration
How is diffusion related to gaseous exchange?
There is a high concentration of oxygen in the alveoli and a low concentration of oxygen in the blood so oxygen diffuses from the alveoli into the blood.
There is also a high concentration in carbon dioxide in the blood and a low concentration in the alveoli so carbon dioxide diffuses from the blood into the alveoli
What is haemoglobin and what does it do?
And iron rich protein in the blood and it carries oxygen to be exchanged at the working muscle and carbon dioxide to be exchanged at the lung
How are the capillaries and alveoli adapted for gaseous exchange ?
Capillary surround the alveoli in the lungs both the capillaries and alveoli are very thin just one cell thick. They are made of semi permeable membrane which allow oxygen and carbon dioxide to pass through them.
