Blood and the circulation Flashcards
what is plasma made up from?
white and red blood cells and platelets.
What does plasma do?
transports various chemicals around the body.
what chemicals does plasma transport around the body?
producs of digestion, hormones, antibodies, urea and carbon dioxide.
what do red blood cells contain?
haemoglobin
what is haemoglobin?
binds to oxygen to transport it from the lungs to the tissues and cells, which it needs for respiration.
what do red blood cells not contain?
a nucleus
what is the shape of a red blood cell?
biconcave disks
what is the purpose of white blood cells?
help to protect the body against infection
true of false: white blood cells can change shape.
True! they can change shape to squeeze out of blood vessels and into the tissues.
what are platlets?
fragments of cells which collect at wounds and trigger blood clotting
how does blood pass around the body?
in blood vessels
what 3 blood vessels does the body contain?
arteries, veins and capillaries.
what do the arteries do?
they take blood from your heart to your organs
What are arteries made from?
thick walls that are made from muscle and elastic fibres.
what do the veins do?
they take blood from your organs to your heart.
what are veins made from?
thinner walls and valves to prevent backflow.
what do capillaries do?
they allow substances needed by the cells to pass out of the blood. they also allow substances produced by the cells to pass into the blood.
what are capillaries made from?
narrow thin walled blood vessels.
what does the heart use to pump blood around the body?
double circulatory system
how many times does the blood circulate through the heart?
twice
what are the four chambers in the heart
the left and right atria, and the left and right ventricles.
what does the left and right atria do?
they recieve blood from the veins
what does the left and right ventricles do?
They pump blood out into arteries
What is the use of valves?
They make sure the blood flows in the correct direction
