animal transport

Question 1

name 2 types of circulatory system

Answer 1

open and closed

Question 2

what does an open circulatory system mean

Answer 2

blood is not always held within blood vessels and can circulate through the body cavity (so cells are immersed directly in the blood)

Question 3

how do insects pump blood towards the head

Answer 3

peristalsis

Question 4

state 3 features of an open circulatory system

Answer 4

• little control over direction of circulation
• no respiratory pigment (insect blood doesn’t contain oxygen or haemoglobin)
• blood pumped at low pressures into fluid filled cavity (haemocoel)

Question 5

what is the fluid filled cavity called (open circulatory system in insects)

Answer 5

haemocoel

Question 6

what does a closed circulatory system mean

Answer 6

the blood is enclosed within the blood vessels and tissues are not in direct contact with the blood (separate fluid exits capillaries and bathes the cells – tissue fluid)

Question 7

what are 3 advantages of closed circulatory systems

Answer 7

• the blood flow is more rapid and efficient
• blood flow can be directed where needed by vasoconstriction/dilation
• more efficient delivery of oxygen and nutrients and removal of waste products

Question 8

whats the separate fluid that bathes the cells called in closed circulatory systems

Answer 8

tissue fluid

Question 9

why can closed circulatory systems pump blood at higher pressure

Answer 9

the tissues are not in contact with the blood and the tissues are bathed in tissue fluid

Question 10

what does a single closed circulatory system mean

Answer 10

the blood stays in vessels on a single pathway around the body, blood only passes through the heart once before returning to the gills

Question 11

describe the route blood takes through a single closed circulatory system in fish

Answer 11

heart –> gills –> body –> heart

Question 12

what does a double circulation system mean

Answer 12

the heart pumps the blood and it goes twice through the heart

Question 13

why do mammals need double circulatory systems

Answer 13

they are endothermic (produce their own body heat), so have high metabolic rate and high energy requirement – cells need large amount of glucose and oxygen and removal of waste products

Question 14

what are the 2 components of the double circulatory system

Answer 14

pulmonary circulatory system, systemic circulatory system

Question 15

explain the route of blood in the pulmonary circulatory system

Answer 15

heart –> lungs –> heart

Question 16

explain the route of blood through the systemic circulatory system

Answer 16

heart –> body –> heart

Question 17

4 advantages of double circulatory system

Answer 17

• heart increases pressure after passing through lungs= blood flows quicker to body tissues
• more efficient delivery of oxygen and nutrients to body tissues
• oxygen supply to heart muscles is better
• systemic circulation can carry blood at higher pressure than pulmonary

Question 18

features of the mammalian heart

Answer 18

4 chambered pump, double pump working synchronously keeping oxygenated and deoxygenated blood separated, cardiac muscle (myogenic) beats from within the muscle itself

Question 19

what does myogenic mean

Answer 19

beats from within the muscle itself

Question 20

another name for red blood cells

Answer 20

erythrocytes

Question 21

another name for white blood cells

Answer 21

leucocytes

Question 22

give 3 features of red blood cells and why they’re good for gas exchange

Answer 22

• biconcave shape - increases SA to carry haemoglobin and oxygen
• no nucleus - can contain more haemoglobin
• very flexible - can fit through capillaries

Question 23

whats the purpose of the septum in the heart

Answer 23

separates the 2 chambers of the heart therefore stops oxygenated and deoxygenated blood from mixing

Question 24

what does systole mean

Answer 24

period of contraction

Question 25

what does diastole mean

Answer 25

period of relaxation

Question 26

name the parts of the heart from top right to top left

Answer 26

vena cava, right atrium, right tricuspid valve, right ventricle, semi-lunar valve, aorta, BODY, pulmonary vein, left atrium, left bicuspid valve, left ventricle, semi-lunar valve, pulmonary artery, LUNGS

Question 27

state the first stage in the cardiac cycle

Answer 27

atria fill with blood from the veins

Question 28

what is relaxed at the first stage of the cycle

Answer 28

all chambers

Question 29

what effect does the atria filling with blood have on the pressure

Answer 29

increases pressure and therefore blood trickles into ventricles and pushes open the atrioventricular valves

Question 30

what does the pressure increasing in the atria do to the atrioventricular valves

Answer 30

pushes them open

Question 31

what is the name of the atrioventricular valve on the right/left side of the heart

Answer 31

right=tricuspid left=bicuspid

Question 32

what does the walls of the atria do after atrioventricular valves are pushed open

Answer 32

contract (atrial systole)

Question 33

why is there a short delay between the contraction of the atria and ventricles

Answer 33

to allow the full contraction of the atria (atrial systole)

Question 34

what happens after the full contraction of the atria

Answer 34

ventricles relax (ventricular systole)

Question 35

which way do the walls of the ventricles contract

Answer 35

from bottom up

Question 36

what's the effect of contracting the ventricles on pressure and volume

Answer 36

decreases volume, increases pressure

Question 37

what's the effect of ventricular systole

Answer 37

pushes shut the atrio-ventricular valves = prevents backflow

Question 38

what's the role of the valves

Answer 38

preventing backflow

Question 39

what sound is produced from the shutting of the atrioventricular valves

Answer 39

lub

Question 40

what is the pressure in the ventricles compared to the pressure in the arteries (pulmonary artery/aorta)

Answer 40

pressure in the ventricles is higher

Question 41

what happens to the semilunar valve when the pressure is greater in the ventricles than the arteries

Answer 41

pushes open the valves and forces blood out of the heart into the arteries

Question 42

what happens to the pressure and semilunar valves when the ventricles relax

Answer 42

pressure falls and semilunar valves shut

Question 43

what noise is produced when the semilunar valves shut

Answer 43

dub

Question 44

what does the SAN stand for

Answer 44

sinoatrial node

Question 45

what does the AVN stand for

Answer 45

atrioventricular node

Question 46

what's the first step in the electrical control of the heart

Answer 46

the SAN initiates an electrical impulse

Question 47

what's the effect of the electrical impulse initiated by the SAN

Answer 47

it spreads over the walls of the atria = causes them to contract (atrial systole) simultaneously

Question 48

what prevents the electrical impulse from travelling to the ventricles

Answer 48

a thin layer of connective tissue (non conductive)

Question 49

where does the electrical signal travel to after the atria

Answer 49

the AVN (atrioventricular node)

Question 50

why does the electrical signal get delayed at the AVN

Answer 50

allows complete contraction of the atria before the ventricles start to contract

Question 51

where does the electrical signal travel to after the AVN

Answer 51

travels down highly conductive tissue in the septum called bundle of His

Question 52

what happens when the electrical signal reaches the bottom of the ventricles

Answer 52

it causes the ventricles to contract

Question 53

where does the electrical signal travel to after contracting the ventricles (bundle of His)

Answer 53

travels up the purkyinje (purkyne) fibres up the sides of the ventricles from the bottom upwards -- ventricular systole

Question 54

what is the result of the ventricular systole

Answer 54

forces blood up into the arteries

Question 55

what happens after the ventricles contract and force blood into the arteries

Answer 55

the electrical impulse is terminated as there is no more conductive tissue

Question 56

what happens as a result of the termination of the electrical signal

Answer 56

the heart goes into a period of relaxation (diastole)

Question 57

what does ECG stand for

Answer 57

electrocardiogram

Question 58

what does the P-wave correspond to on an ECG

Answer 58

atrial systole

Question 59

what does the QRS complex correspond to on an ECG

Answer 59

ventricular systole

Question 60

what does the T-wave correspond to on an ECG

Answer 60

diastole (heart recovering)

Question 61

what does trachycardiac mean

Answer 61

higher heart rate for no reason

Question 62

what does heart block look like on an ECG

Answer 62

delay between P and QRS complex -- delay in conduction between atria and ventricles

Question 63

what does ventricular fibrillation look like on an ECG

Answer 63

uncoordinated and weak contractions - fluttering - little blood is pumped

Question 64

what does atrial fibrillation look like on an ECG

Answer 64

narrow and repeated QRS complex and no visible P waves