B5 - Respiratory systems Flashcards
What is breathing?
Breathing is the exchange of gases.
What is respiration?
Respiration is the release of energy from food.
What is gaseous exchange?
The movement of gases across an exchange membrane e.g lungs.
Why do earthworms dig deeper into the soil in dry weather?
Their skin must be moist for oxygen to dissolve in so they will need moisture from deeper in the soil.
What is the scientific name for a windpipe?
The windpipe is called the trachea.
What two structures protect the lungs?
The ribs protect the lungs and pleural membrane surrounds the lungs.
What is a spirometer?
An instrument for measuring the air capacity of the lungs.
What is the overall amount of air that you can breathe called?
This is called the tidal capacity.
What is the small amount of air that cannot be breathed out called?
This is called the residual capacity.
Why is the residual capacity necessary?
To prevent alveoli from sticking together.
Describe what happens to the diaphragm, intercostal muscles and the ribs as air is breathed in.
The diaphragm contracts and flattens out, the intercostal muscles contract and the ribs move out and up.
Describe what happens to the diaphragm, intercostal muscles and the ribs as air is breathed out.
The diaphragm relaxes and stretches, the intercostal muscles relax and the ribs move down and in.
Why does the diaphragm flatten when it contracts?
So that it creates a vacuum and inflates the lungs with air.
What happens to the volume in the lungs when air is breathed in?
Lung volume increases.
What happens to the pressure in the lungs when air is breathed in?
Lung pressure decreases.
What happens to the volume in the lungs when air is breathed out?
Lung volume decreases.
What happens to the pressure in the lungs when air is breathed out?
Lung pressure increases.
Why does diffusion take place in the lungs?
The air entering the lungs has a higher amount of oxygen than the deoxygenated blood flowing through the lungs so diffusion takes place.
Where does gaseous exchange take place?
In the alveoli.
Why does carbon dioxide diffuse out of the blood?
Because the blood contains a higher concentration of carbon dioxide than the air does.
What is an alveoli?
The alveoli are the tiny air sacs in the lungs through which the exchange of oxygen and carbon dioxide takes place.
How are the alveoli adapted to be efficient gas exchangers?
- a large surface area
- a moist surface
- a thin permeable lining
- a good blood supply
Why does the surface area where gaseous exchange takes place need to be as large as possible?
So that the exchange of gases is quicker and more effective.
What is asthma?
A condition where airways are restricted and inflamed.
