Breathing and Cirulation Flashcards
(34 cards)
What are the walls of the heart made of
Muscle tissue
What do valves do
Makes sure the blood doesn’t flow backwards
What is the bloods path in the heart
Vena carva R.Atrium R.Ventricle Pulmonary Artey L.Atrium L.Ventricle Out
How does this pacemaker work
Electric impulses cause the surrounding muscle cells to contract
What happens if your natural pacemaker breaks/doesn’t work properly
Replace with an arteficial pacemaker
How does an arteficial pacemaker work
Device planted under skin
Has wire going to heart
Produces an electric current to keeo heart beating
What are the three types of blood vessels
Veins
Arteries
Capilaries
What do arteries do
Carry blood away from heart to organs/tissues
What do veins do
Veins carry blood to the heart
What do capillaries do
Capilaries exchange materials in organs/tissues
How are arteries adapted to carry out its function
Walls are strong and elastic
Layers of muscle and elastic fibres
How are capillaries adapted to carry out their function
They have a thin permeable walls to speed up diffusion
What do capillaries do in diffusion
Supply cells (organ cells) with food and oxygen Take away waste products like CO2
Why don’t vein walls need to be as thick as artery walls
Because veins carry blood at lower pressure
What allows the blood to flow in the right direction in veins
Valves
What is the inside “tube” called in veins/arteries
Lumen
What is the job of red blood cells
To carry oxygen from the lungs to the cells of the body
Why is the red blood cell shaped like a doughnut
To increase surface area to absorb more oxygen
Why don’t red blood cells have a nucleus
To allow more room for oxygen
Why are red blood cells red
Contain red pigment called haemoglobin
What are platelets
Platelets help the blood clot
What is plasma
Carries most things in blood: RBC and WBC, nutrients, CO2, urea, hormones, antibodies and antitoxins
Why do some organ donors organs get rejected by the body
Because our immune system sees foreign antigens (of the organ) so it sends antibodies to attack it
What do we do to avoid rejection
Look for donors of similar tissue types
Take drugs to suppress immune system so organ wont be attacked
