B4 Flashcards
what are the main types of blood vessels
veins, arteries and capilaries
what are the features of a red blood cell which helps it deliver oxygen to your cells
has lots of haemoglobin for oxygen to bind to, biconcave shape for a larger surface area, no nucleus for more haemoglobin to fit in the cell,
what is the blood of a healthy person mostly made of (all the main components in blood)
plasma, red blood cells, white blood cells, platelets
what is the role of white blood cells
to fight of harmful organisms
what is the role of plasma
transports undigested food and body waste
what is the role of platelets
fragments of cells which help create blood clots
what is the role of the artery
to carry blood away from the heart
what is the role of the vein
to carry blood to the heart
what is the pressure of the blood carried in the artery
its carried at high pressures so the blood moves fast
what is the pressure of the blood carried by the vein
blood in the vein is carried in low pressure which makes the blood travel slowly
what are the adaptations of the arteries which makes it suitable for carrying blood at high pressures
thick inner and outer walls of muscles with a narrow central tube
what are the adaptations of the veins which makes them suitable for carrying blood at low pressures
they have thin outer and inner walls of muscles with a wide central tube
why is blood in the arteries carried at high pressures but not in the veins
blood in the arteries are carried at high pressures because it’s needed to flow quickly to every parts of the body so that cells don’t die due to lack of oxygen. veins don’t need to carry blood at high pressures because… well you don’t need to know the reason.
why do veins have valves
the role of the valve is to prevent backflow by opening and closing. when valves open the allow blood to enter and o towards the heart but then the close in case the blood starts to flow back the way it came from.
how do valves in a vein work
when blood moves up the vein it pushes the valve causing it to open and so blood is allowed to move past it. however if blood does start to flow backwards it pushes the valve to close.
how does blood move up the vein
there are muscles to the side of the veins which pushes the blood up the vein. think of it as a tube of toothpaste and a rolling pin. the pin pushes the toothpaste out of the tube.
what is the role of the capillary
carries blood to and from the body’s cell to exchange substances between the blood and other bodily cells
what are the adaptations of the capillaries which makes it suitable for the exchange of substances?
it’s 1 layer thick which makes it easy for substances to pass through the capillary and go towards the cell and it has a narrow central tube.
how do the capillaries work
substances are exchanged by diffusion through the capillary wall.
useful substance diffuse across the capillary wall to the cells from the blood and waste substances diffuse from the cells to the blood. capillaries are narrow to slow down blood and lower the blood pressure.
what is a double circulatory system
one system brings blood from the heart to the lungs and back whilst the other carries it from the heart to the rest of the body.
why is a double circulatory system important
as areas will receive oxygenated blood more quickly
how does a platelet form clot
platelets release a special protein which ties up red blood cells and some other platelets to form a clot. that clot then hardens and dries up to prevent microorganisms from entering the body. think of it like spider creating webs to catch insects (the bacteria).
what is the heart
it’s a muscular organ which pumps blood around the body.
what is the job of the coronary artery and vein
coronary artery- takes blood from the heart to the heart muscles.
coronary vein- takes blood from the heart muscles back to the heart.
what is the role of the pulmonary artery
takes deoxygenated blood from the heart to the lungs
what is the role of the vena cava
takes deoxygenated blood from the body to the heart
what is the role of the aorta
takes oxygenated blood from the heart to the rest of the body
what is the role of the pulmonary vein
takes oxygenated blood from the lungs to the heart
where is the pulmonary artery located
at the the very top of the heart on the right hand side. remember in a heart diagram right is left and left is right so when i’m saying ‘right hand side’ it’ll be to YOUR left.
where is the vena cava located
on the top-middle of the right hand side. remember in a heart diagram right is left and left is right so when i’m saying ‘right hand side’ it’ll be to YOUR left.
where is the aorta located
at the very to of the left hand side of the heart. remember in a heart diagram right is left and left is right so when i’m saying ‘left hand side’ it’ll be to YOUR right.
where is the pulmonary vein located
on the top-middle of the left hand side. remember in a heart diagram right is left and left is right so when i’m saying ‘left hand side’ it’ll be to YOUR right.
what does it mean when someone says they have a hole in their heart
that means the wall separating oxygenated and deoxygenated blood (called the septum) has a hole in it and so that the oxygenated blood and deoxygenated blood mix.
why dos the heart have valves
to prevent the blood from going back towards the atriums
where are BOTH of the atriums located
the are at both sides, at the top of the heart. the blood always flows into the atrium first whether its from the pulmonary vein or the vena cava. the atriums are located above the ventricles
what’s a thrombosis
a blood clot which blocks the vessels coronary arteries
what is a coronary heart disease
when cholesterol sticks to the sides of blood vessels which means that there’s a blood clot and blocks the vessels
how do you treat a coronary heart disease
bypasss surgery - when bits of vein are used to replace blocked coronary arteries
statins - drugs which reduces blood cholesterol levels
stents - a tiny metal mesh inserted in artery with a small balloon. the balloon is used to expand the metal mesh and artery at the same time. the artery is then kept in place by the metal mesh. the balloon is then removed.
what is a leaky valve
when a heart valve starts to leak or become stiff and not fully open
what is a pacemaker
a group of cells in the right atrium which controls the rate at which the heart beats
what is an artificial pacemaker and what’s it used for
its an electrical device which is implanted in your chest which send strong electrical impulses to your heart which tells it to beat
