Topic 2- The Respiratory System Flashcards
When inhaling what happens to the pressure in the lungs?
It increases
When does the air pressure in the lungs change?
According to whether the body is inhaling or exhaling
What happens to the pressure in the lungs when exhaling?
It decreases
What is the function of the diaphragm?
To change the pressure in the lungs
What happens to oxygen when breathed in?
The oxygen diffuses through the alveoli into the blood stream
What happens to carbon dioxide in the blood stream?
It diffuses from the blood stream into the alveoli and breathed out
What type of organ is the lungs?
Organs of gas exchange
What is the main structures of the lungs?(3)
The trachea
Bronchus
Bronchioles
What are the lungs composed of?
Alveoli which are surrounded by a dense network if capillaries
What does the trachea have around it?
Cartilage
What is the purpose of the cartilage?
To give structure and support, it keeps the trachea open and allows it to remain flexible
What are cilia?
Hairs lining the trachea which move mucus to the larynx
What is mucus?
A hick sticky liquid
Where is mucus produced?
In the mucus secreting cells lining the trachea and bronchi
Why do we need mucus?
Small particles that are breathed in gets stuck an trapped in the mucus
It also helps keep the surface of the lungs moist
Give 3 examples of small particles that can get trapped in the mucus
Dust
Pollen
Bacteria
How do the cilia move?
They move in a wave like motion and cause the mucus to move from the lungs to the top of the trachea
How does air enter the body?
Through the nose and mouth
Where does the air go once it enters through the mouth or nose?
It travels down the trachea into the lungs where gas exchange occurs
How does the lungs have a large surface area?
The thousands of alveoli and capillaries
How is the alveoli efficient at gas exchange?
The membrane walls are very thin therefore gas diffuses quickly
How are capillaries efficient at gas exchange?
Their walls are one cell thick so gases can diffuse quickly
How is oxygen able to dissolve for going into the blood stream?
The surface of the alveoli are moist to allow the oxygen to diffuse easily
How does a dense network of capillaries make gas exchange efficient?
They are very close to the alveoli which ensures a short distance that gases have to travel and so more rapid diffusion
