circulation

Question 1

what is an open circulatory system

Answer 1

blood isn’t contained within blood vessels, but pumped directly into body cavities

Question 1

what is a closed circulatory system

Answer 1

blood is pumped around the body and is always contained in a network of blood vessels

Question 2

what is the name given to arteries and veins that connect to the head and neck

Answer 2

carotid ___

Question 2

what is the name given to arteries and veins that connect to the lungs

Answer 2

pulmonary ___

Question 3

what is the name given to arteries and veins that connect to the liver

Answer 3

hepatic ___

Question 4

what is the name given to arteries and veins that connect to the kidneys

Answer 4

renal ____

Question 5

what are capillaries and how are hey adapted to their function

Answer 5

tiny blood vessels that connect arterioles and venules
small + 1 cell thick - decreased diffusion distance increasing the rate of gas exchange

Question 5

how are arteries adapted to their function

Answer 5

muscular, elastic walls : withstand high blood pressure
narrow lumen: maintain high blood pressure

Question 5

what are arterioles

Answer 5

small arteries which branch from larger arteries and connect to capillaries

Question 6

what are venules

Answer 6

small veins that connect capillaries to larger veins

Question 7

what are veins and how are they adapted to their function

Answer 7

carry blood towards heart
thinner walls, thicker lumen
have valves so blood doesn’t back flow (with gravity)

Question 8

what is tissue fluid

Answer 8

the body fluid surrounding the cells in tissues

Question 9

what is in tissue fluid

Answer 9

contains water and nutrients
holds waste products released by cells due to metabolism

Question 10

define water potential

Answer 10

potential of water to move from one place to another

Question 11

what is the equation for water potential

Answer 11

water potential = pressure potential + solute potential

Question 12

how does tissue fluid form

Answer 12

• in capillaries, at arteriole end, blood pressure is higher
• so water moves out of capillary by osmosis

Question 13

how does tissue fluid drain

Answer 13

• at venue end of capillary, hydrostatic pressure is lower
• so water moves back into capillary
• by the lymphatic system

Question 14

how much tissue fluid drains into the lymphatic system

Answer 14

5-10%

Question 15

what happens during ventricular systole (contraction)

Answer 15

atria: relaxes
ventricles: contracts
semi-lunar valves: open
filling/ejection: artery ejection

Question 15

how does higher blood pressure form more tissue fluid

Answer 15

faster blood flow
more water squeezed out
more tissue fluid formed
builds at bottom of body due to graviy

Question 16

what happens during atrial systole ( contraction)

Answer 16

atria: contracts
ventricles: relaxes
semi-lunar valves: closed
filling/ejection: ventricle fills

Question 17

what happens during ventricular diastole (relaxation)

Answer 17

atria: relaxes
ventricles: relaxes
semi-lunar valves: closed
filling/ejection: atrial filling

Question 17

what is it called when the heart contracts involentarily

Answer 17

meiogenic
can contract + relax without external nervous system

Question 18

how blood moves through heart

Answer 18

Deoxygenated Blood:
Enters the right atrium from the body via the vena cava.
Moves to the right ventricle.
Pumped to the lungs through the pulmonary arteries for oxygenation.
Oxygenated Blood:
Returns to the left atrium from the lungs via the pulmonary veins.
Moves to the left ventricle.
Pumped to the rest of the body through the aorta.

Question 19

what are the parts of the heart involved in the electrical conduction system of the heart 6

Answer 19

SAN AV node non-conducting tissue his bundle right + left bundle branches purkinje fibres

Question 20

what part of the heart starts electrical activity and where is it

Answer 20

SAN found near vena cava

Question 21

what happens after SAN starts electrical impulse

Answer 21

there is a wave of excitation across the atria causing atrial systole (contraction)

Question 22

what prevents the electricity immediately flowing into the ventricles

Answer 22

non-conducting tissue

Question 23

where is the wave of electricity then directed to after the non-conducting tissue redirects it

Answer 23

the AV node

Question 24

what does the AV node do

Answer 24

causes a delay allowing blood to flow into the ventricle and allowing atria to fully contract

Question 25

when electrical wave reaches ventricles, how does it move

Answer 25

to bundle of his down right and left bundle branches up purkinje fibres

Question 26

what direction does the contraction move in the ventricles

Answer 26

from base, upwards forcing blood up and out through arteries

Question 27

what is the P wave on a electrocardiogram

Answer 27

atrial contraction

Question 28

what is the QRS wave on an electrocardiogram

Answer 28

activation of ventricles

Question 29

what id the T wave on an electrocardiogram

Answer 29

recovery wave

Question 30

what causes increased CO2 in blood

Answer 30

increased muscular/metabollic activity making tissue cells respire, producing CO2

Question 31

what happens to the blood ph when there is more co2 in the blood

Answer 31

ph decreases as carbonic acid forms

Question 31

what detects the change in ph in blood and where are they

Answer 31

chemoreceptors in the carotid arteries in the neck

Question 32

what do the chemoreceptors do when the ph of blood is lower

Answer 32

it sends an increased frequency of impulses to the medulla oblongata

Question 33

where is the medulla oblongata

Answer 33

the brain

Question 34

what does the medulla oblongata do when it has and increased frequency of impulses

Answer 34

it increases the frequency of impulses down the sympathetic nerve to the SAN increasing heart rate

Question 35

how are capillaries adapted for exchange of substances 4

Answer 35

-permeable walls -single cell thick walls -small - SA:V ratio -narrow lumen reduces blood flow + rbc in contact w walls

Question 36

which sides of the heart pumps blood around the whole body and the lungs

Answer 36

Right: lungs Left: whole bod