Organisation - the circulatory system Flashcards
where are the lungs
in the thorax ( top part of your body ) and are protected by the ribcage
how does air travel through the lungs
- goes in through the trachea ( windpipe )
- this splits into two tubes called bronchi
- these then split into smaller tubes called bronchioles
- the bronchioles finally end at small bags called alveoli where the gas exchange takes place
what are alveoli
little air sacs that carry out gas exchange
describe gas exchange
1 -blood returns to body from lungs with a lot of co2 and not much o2
2- oxygen diffuses out the alveolus ( high conc) into the blood ( low conc ) then co2 diffuses out of the blood and into the alveolius to be breathed out
3- when the blood reaches body cells, oxygen is released from the red blood cells ( high conc ) and diffuses into the body cells ( low conc )
4 - at the same time, carbon dioxide diffuses out of body cells ( high conc ) into the blood ( where theres low conc ) , its then carried back to lungs
what happens in the first circuit of the double circulatory system
the right ventricle pumps deoxygenated blood to the lungs to take in oxygen, the blood then returns to the heart
what happens in the second circuit of the double circulatory system
the left ventricle pumps oxygenated blood around all the other organs of the body
- the blood gives up its oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the lungs again
what does the heart do
contracts to pump blood around the body
what is the heart
a pumping organ that keeps blood flowing around the body, walls mostly made of muscle tissue
why does the heart have valves
to make sure blood flows in the right direction
- prevents it from flowing backwards
how many chambers are in the heart
4
what are the hearts chambers
right atrium, right ventricle, left atrium, left ventricle
what parts of the heart are on the right side
right atrium, right ventricle, vena cava, pulmonary artery
what parts of the heart are on the left side
aorta, pulmonary vein, left atrium, left ventricle
how does blood go around the BODY
1 - the vena cava brings in deoxygenated blood from the body
2. the blood then passes from the heart to the lungs in the pulmonary artery
- in the lungs, the blood collects oxygen
- oxygenated blood passes from the lungs to the heart in the pulmonary vein
- Oxygenated blood is pumped from the heart to the body in the aorta
what are coronary arteries
supply heart with oxygen
what is a pacemaker
- a group of cells in the right atrium wall that control resting heart rate
what is an artificial pacemaker
- a small device that’s placed (implanted) in the chest to help control the heartbeat
three types of blood vessels
- arteries
- capillaries
- veins