Circulatory System Flashcards
what is the main function of the circulatory system
get food and oxygen to every cell in the body
what is a secondary function of the circulatory system
takes waste products like carbon dioxide and urea to where they can be removed
the human body has a double circulatory system, what does the first part do
moves deoxygenated blood to the lungs
then to the heart
what does the second part do
pumps oxygenated blood to the other organs
what does the heart do to pump blood round the body
contracts
what are the walls of the heart made from
muscle tissue
what prevents the blood from flowing the wrong direction
valves
how many chambers are there in the heart and what are the names
4
right and left atrium
right and left centricle
what are the 5 stages of blood flowing round the heart and the body
blood flows into the two atria from pulmonary vein and vena cava
atria contract
ventricles contract forcing blood out of heart
blood flows round body
then into atria and cycle starts again
what are the three blood vessels called
arteries capillaries and veins
what are the three vessels jobs
arteries blood away from heart
capillaries exchange of materials
veins blood to the heart
how do arteries carry blood
under pressure
what are the artery walls like
strong
elastic
thick
what do artery walls contain
muscle tissue
how big are capillaries
very small
what are capillary walls like
permeable
1 cell thick
what do capillaries join up to form
veins
what pressure is the blood at in veins
low
what keeps blood flowing in the right direction in veins
valves
what do red blood cells carry
oxygen
what shape are red blood cells
a doughnut shape
what is the red pigment red blood cells contain called
haemoglobin
what do white blood cells do
defend against disease
how do white blood cells fight disease
change shape to engulf unwanted microbes
produce antibodies
produce antitoxins
