Topic 3 - Cardio-respiratory system Flashcards
Describe the passage of air into the lungs
Air enters the body and is warmed as it travels through the mouth and nose.
It then enters the trachea.
The trachea divides into two bronchi. One bronchus enters each lung.
Each bronchus branches out into smaller tubes called bronchioles. Air travels through these bronchioles.
At the end of the bronchioles, the air enters one of the many millions of alveoli where gaseous exchange takes place.
Where does gaseous exchange occur
In the alveoli in the lungs
What is diffusion
The movement of molecules from an area of high concentration to low concentration
What happens at the muscles (diffusion)
Oxygen diffuses into the blood from the alveoli and carbon dioxide diffuses into the alveoli from the blood
Why are capillaries and alveoli walls made of semi-permeable membrane
So they allow oxygen and carbon dioxide to pass through them
What is there a high concentration of in the muscle
carbon dioxide
What is there high concentration of in the blood stream
oxygen
What is vital capacity
The max amount of air that can be breathed out after breathing in as much air as possible
What is breathing rate
The number of breaths per minute
What is tidal volume
The amount of air breathed in with each normal breath
What is minute ventilation
total volume of air entering the lungs in a minute
What is the formula for minute ventilation
breathing rate x tidal volume
What do the muscles need more of in order to contract and what is produced more
oxygen is needed to contract and more carbon dioxide is produced as a waste product
What happens when tidal volume and rate increase
More oxygen gets into the lungs and removes more carbon dioxide out of the lungs
What happens when heart rate increases
this increases the rate that oxygen is transported from the blood to the working muscles and carbon dioxide is transported from the working muscles to the lungs.
