the heart and circulatory system

Question 1

what do arteries do

Answer 1

carry blood away from the heart

Question 2

how is blood pumped out of the arteries

Answer 2

at high pressures

Question 3

what are muscles in the arteries like

Answer 3

thick compared to the lumen, there are layers of muscle in the walls to make them strong

Question 4

what allows the muscles in arteries to stretch and recoil

Answer 4

elastic fibres which helps withstand pressure created by pumping of blood

Question 5

what do veins do

Answer 5

take blood back to the heart

Question 6

what is blood like in the veins

Answer 6

at low pressure

Question 7

what is the structure of the veins like

Answer 7

bigger lumen than arteries to help blood flow despite low pressures

Question 8

what do capillaries join up to form

Answer 8

veins

Question 9

what do arteries branch out into

Answer 9

capillaries

Question 10

how are capillaries adapted to help exchange of substances

Answer 10

one cell thick to allow blood to flow really close to every cell in the body

Question 11

why are capillaries narrow

Answer 11

to squeeze into gaps between cells

Question 12

why do capillaries have a permeable wall

Answer 12

so substances can diffuse in and out

Question 13

What is the role of the right atrium

Answer 13

receives deoxygenated blood through the vena cava from the body at LOW PRESSURE

Question 14

where does the blood go after the right atrium

Answer 14

right ventricle

Question 15

what does the right ventricle do

Answer 15

contracts to pump blood to the kings where it is oxygenated

Question 16

where does blood go after the right ventricle

Answer 16

left atrium

Question 17

what happens in the left atrium

Answer 17

receives oxygenated blood from the lungs through pulmonary vein still at low pressure

Question 18

where does blood flow to after the left atrium

Answer 18

left ventricle

Question 19

what happens in the left ventricle

Answer 19

oxygenated blood enters the left ventricle which contracts to pump it round the whole body via the aorta

Question 20

why does the left ventricle have a much thicker wall

Answer 20

has to pump blood round the whole body at high pressure

Question 21

what provides a strong heartbeat

Answer 21

muscular walls

Question 22

what is the role of the septum

Answer 22

ensures that deoxygenated and oxygenated blood don’t mix

Question 23

why does the heart have valves

Answer 23

stop back flow of blood so blood keeps flowing forward

Question 24

what is cardiac output

Answer 24

volume of blood pumped out of the heart in a minute