cardiovascular system

Question 1

what is the cardiovascular system made up of

Answer 1

heart, blood vessels, blood

Question 2

why is the heart called a double circulatory system

Answer 2

there are two different circulations and the heart acts a a link between the two, one side pumps deoxygenated blood back to the heart from the body and the other side pumps oxygenated blood around the body

Question 3

explain how the pulmonary circulatory system works

Answer 3

the heart pump blood to the lungs, where it picks up oxygen to become oxygenated, in the lungs carbon dioxide is also diffused out of blood,
blood then returns to the heart using veins

Question 4

explain how the systematic circulatory system works

Answer 4

heart pumps blood so that it flows into arteries and reaching capillaries in the body, here the oxygen in the blood diffuses out and carbon dioxide is produced.
deoxygenated blood is then transported back to the heart using blood vessels and veins

Question 5

which side of the heart deals with oxygenated blood?

Answer 5

the left side, left ventricle pumping blood all around the body

Question 6

which side of the heart deals with deoxygenated blood

Answer 6

the right side

Question 7

what do arteries do

Answer 7

supply oxygenated blood to the heart muscles so it can contract.

Question 8

what are the names of the two arteries that are at the top of the atriums

Answer 8

the aorta and the pulmonary artery,
they carry blood away from the the bottom chambers, the ventricles .

Question 9

what are the names of the two major veins, what do they do

Answer 9

the vena cava and the pulmonary vein
they carry blood into the heart and into the top chambers, the atriums

Question 10

describe the pathway of blood around the circulatory system

Answer 10

in the lungs oxygen is picked up by the lungs, this then travels from the lungs, entering the left atrium via the pulmonary vein.
deoxygenated blood travels from the body and enters the right atrium via the vena cava to get more oxygen through the lungs. this process repeats itself

Question 11

what happens when the atriums contract

Answer 11

blood is forced into the ventricles which is below them, the blood goes through the atrioventricular valves ( AV valves)

Question 12

how do these valves prevent blood from flowing the wrong way

Answer 12

they are attached to the walls of the heart by tendinous cords, they prevent them from turning inside out

Question 13

what happens when the left ventricle contracts

Answer 13

blood leaves the heart, going into the body through arteries, oxygenated blood gets pumped out of the body by the left ventricle , by the aorta and supplying blood to all parts of the body.

Question 14

what happens when the right ventricle contracts

Answer 14

deoxygenated blood is pumped through the ventricle into the lungs to be reoxygenated, via the pulmonary artery

Question 15

what are the valves that are at the base of the aorta and pulmonary artery

Answer 15

they are the semi lunar valves, they prevent blood from going back into the ventricles when the heart relaxes

Question 16

what is the septum and where do you find it

Answer 16

the septum is a wall of muscle in the middle of the heart that separates the ventricles from each other , ensuring oxygenated blood and deoxygenated blood do not mix

Question 17

explain the cardiac cycles 5 steps

Answer 17

• the atria both fill up with blood, this is called ATRIAL SYSTOLE.
  -the atria contract and force AV valves to open, blood flows into the ventricles and they fill up, VENTRICULAR DIASTOLE
• the av valves close when pressure in ventricles rises, to prevent backflow.
• ventricle walls contract and increase the pressure in the ventricles, forces semi lunar valves to open so blood flows into both arteries on each side of the heart .
• the semi lunar valves then close up, after this there is a short delay before VENTRICULAR SYSTOLE, this is where the ventricles contract at the same time.
• there is then another short pause where all chambers relax and fill again, this is called DIASTOLE

Question 18

what is the sino- atrial node (SAN)

Answer 18

a node that generates electrical activity in the heart to initiate beats, also known as a pace maker. it causes both atria to contract

Question 19

what is plasma

Answer 19

liquid part of blood, contains proteins,amino acids, glucose

Question 20

describe red blood cells

Answer 20

their role is to transport oxygen throughout the body, they have a biconcave shape to them which allows them to hold more oxygen and they also have no nucleus, haemoglobin allows them to hold more oxygen too

Question 21

what do platelets do

Answer 21

they promote blood clotting

Question 22

why does the right side of the heart not need thicker muscle walls

Answer 22

because there is not high blood pressure as the blood is not oxygenated, if there was high blood pressure this would cause damage to the aveoli in the lungs

Question 23

describe the features of arteries

Answer 23

they have a thin lumen to increase blood pressure
they have thick muscle walls so that they can take the pressure of the blood
elastic tissue so they can withstand high pressure
smooth endothelium to reduce friction
pulse, no valves

Question 24

describe arterioles features

Answer 24

they are smaller vessels that come after the arteroes that help with sending blood to other parts of the body, they dialate to increase blood flow, as the lumen largens
they have thinner elastic as the pressure lowers

Question 25

describe the features of veins

Answer 25

they carry blood back to the heart they have a very large lumen and they also have valves inside of them to prevent the backflow of blood, this outer layer with low amount of muscle as it is not needed because there is not high blood pressure. no pulse

Question 26

describe the features of capillaries

Answer 26

they are important in the exchange of gases and nutrients inside of the body, they have a very thin layer 1 cell thick which allows for a short diffusion distance - this increases the speed of diffusion/ rate narrow lumen which reduces flow rate so there is more time for diffusion pores in the wall partially permeable membrane so things can come in and out e.g white blood cells can come out

Question 27

what does the renal artery do

Answer 27

carries large amounts of blood to the kidneys

Question 28

what does the renal vein do

Answer 28

carries deoxygenated blood from the kidneys to the aorta so it can be oxygenated again

Question 29

what are baroreceptors

Answer 29

they an detect changes in blood pressure, the are found in the aorta, they help the heart to know that it should reduce heart rate when blood pressure is high and increase it when blood pressure is low

Question 30

what are changes to the cardiac output regulated by what does this lead to

Answer 30

the autonomic nervous system,the ANS sends signals from the brain to release more NORADRENALINE to stimulate the SAN this leads to an increase of the frequency of signals being sent by the SAN/ pacemaker so the heart beats more quickly. and increase the force of contractions.

Question 31

give an example where cardiac output would been to be changed

Answer 31

during exercise when the heart needs to beat faster

Question 32

what do chemoreceptors do

Answer 32

they detect changes in PH eg when blood carbon dioxide levels rise, blood ph falls and this is detected by chemoreceptors.

Question 33

what is the normal blood pressure range for a healthy person

Answer 33

120/80mmHg

Question 34

what does the first number in a blood pressure reading mean

Answer 34

the pressure of the artery when ventricle contract, this is called the systolic pressure. the highest number will always be first in a blood pressure reading. 10 is a healthy range for this

Question 35

what does the second number mean in a blood pressure reading

Answer 35

the pressure in the artery when the heart relaxes, diastolic pressure, 80 i a healthy range for this

Question 36

how do the kidneys play a role in blood pressure

Answer 36

they control water volume in the body, if an increased volume of water is lot from the body, by urine then blood pressure is decreased, if more water is conserved then blood pressure increases

Question 37

what is tissue fluid

Answer 37

the fluid found in spaces around cells, comes from substances that leak out of capillaries

Question 38

what does it help with

Answer 38

substance exchange between cells and it helps with bringing oxygen and nutrients to cells