The Circulatory system - The Lungs Flashcards
What is the function of the Lungs?
The lungs are the site of gas exchange.
Oxygen is taken from the atmosphere into the bloodstream and Carbon dioxide is released into the surroundings.
What is the Thorax?
The top part of the body is separated from the lower part of the body (abdomen) by the muscle called the diaphragm.
What are Lungs?
They are big pink sponges that are protected by the ribcage and surrounded by the pleural membrane.
Explain the structure of the lungs
When you inhale air from the atmosphere, it passes through the mouth and into the trachea (windpipe)
The trachea then splits into bronchi (tube-like structures) which go into each lung.
The bronchi then split again into branch-like tube tubes called bronchioles
At the end of the bronchioles are small air sack that are called Alveoli (this is where the gas exchange takes place)
What are alveoli?
They are small air sacks surrounded by capillaries where gas exchange takes place
How does the gas exchange work?
The blood that transported oxygen returns back to the lungs; this is deoxygenated blood with a lot of carbon dioxide
The Carbon dioxide will diffuse out of the blood, through the capillaries, and into the alveoli in the lungs for it to be exhaled
High concentration (Blood) —>Low concentration (Alveoli)
The Oxygen will diffuse out of the alveoli, through the capillaries, and into the bloodstream to be used in cellular respiration.
High concentration (alveoli) —> Low concentration (blood)
Properties of alveoli:
Larger surface area and one cell thick for an increased rate of diffusion.
Moist for the gases to be easily dissolved
