chapter 8: transport in animals

Question 1

4 reasons specialised transport systems are needed in animals

Answer 1

high metabolic demand
low SA:V
molecules are made in one place but needed in another
remove waste products

Question 2

difference between single and double circulatory system

Answer 2

single - blood goes through heart once for each lap of body
double - blood goes through heart twice for each lap of body

Question 2

what do arterioles and venules do

Answer 2

link arteries and capillaries
link veins and capillaries

Question 2

difference between open and closed circulatory system

Answer 2

open - few vessels to contain the transport medium. pumped straight from heart to body cavity. comes into contact with cells. transport medium returns to heart through an open ended vessel
closed - blood enclosed in vessels. doesn’t come in contact with body cells. blood returns directly to the heart.

Question 3

3 components in blood vessels and what they do

Answer 3

elastic fibres - composed of elastin and can stretch and recoil meaning vessel is flexible
smooth muscle - contracts and relaxes which changes the size of the lumen
collagen - provides structural support to maintain volume and shape of vessel

Question 4

whats vasoconstriction

Answer 4

when the smooth muscle in the arteriole contracts and prevents blood flowing into a capillary bed

Question 5

whats vasodilation

Answer 5

when smooth muscle in arterioles relax and blood flows through the capillary bed.

Question 6

how are capillaries adapted for their function

Answer 6

LSA

Question 7

differences between a vein components and venule components

Answer 7

venule has no elastin or smooth muscle but has collagen.
vein has all 3

Question 8

3 adaptations that make blood flow against gravity

Answer 8

1 way valves - keeps blood flowing in 1 direction
vein runs between muscles - when they contract, they force blood to move
breathing movements of chest acts as a pump.

Question 9

5 things blood transport

Answer 9

O2
CO2
digested food
hormones
waste products

Question 10

why does water move into the blood in capillaries from tissue fluid

Answer 10

oncotic pressure

Question 11

whats hydrostatic pressure

Answer 11

pressure from surge of blood that occurs every time the heart contracts

Question 12

at what end of the capillaries is fluid moved out.

Answer 12

arteriole

Question 13

why does fluid move out of the arterial end of the capillary into the tissue

Answer 13

hydrostatic pressure is greater than oncotic pressure

Question 14

whats tissue fluid

Answer 14

the fluid that fills spaces between cells

Question 15

what pressure is greatest at arteriole end so where does fluid move

Answer 15

hydrostatic. into tissue

Question 16

what pressure is greatest at venule end so where does fluid move

Answer 16

oncotic. into capillary

Question 17

at what end of the capillary is fluid moved in

Answer 17

venule

Question 18

whats lymph

Answer 18

tissue fluid thats collected in the lymph system

Question 19

what extra thing is in lymph that isnt in blood plasma and where does it get it from

Answer 19

fatty acids from small intestine

Question 20

how does lymph return to the blood

Answer 20

lymph vessels

Question 21

what is contain in lymph nodes

Answer 21

lymphocytes

Question 22

whats oxyhaemoglobin made up of

Answer 22

haemoglobin and 4 oxygens

Question 22

whaty does an oxygen disassociation curve show.

Answer 22

the affinity of haemoglobin to O2

Question 23

how are the oxygens and haemoglobins positively cooperating

Answer 23

when one O2 binds to a haem group, the tertiary structure changes shape, making it easier for the next O2 to bind

Question 24

at high partial pressure of O2, are many or few haem groups bound to O2. what does this mean for saturation

Answer 24

lots bound. saturated

Question 25

at low partial pressure of O2, are many or few haem groups bound to O2. what does this mean for saturation

Answer 25

few bound. not saturated

Question 26

explain the bohr effect

Answer 26

at higher partial pressures of CO2, haemoglobin gives up O2 more easily

Question 27

2 results of the bohr effect

Answer 27

in active tissues with high partial pressure of CO2, haemoglobin gives up its o2 more easily in the lungs where there's a low proportion of CO2, O2 binds to haemoglobin easily

Question 28

explain chloride shift

Answer 28

negatively charged hydrogen carbonate ions move out of erythrocytes into plasma by diffusion. negatively charged chloride ions move into erythrocytes, maintaining electrical balance of the cell.

Question 28

where is tricuspid valve

Answer 28

between right atrium and ventricle

Question 28

3 forms of CO2 as its transported round the body

Answer 28

hydrogen carbonate, carbaminohaemoglobin, dissolved in plasma

Question 29

what is most CO2 transported as

Answer 29

hydrogen carbonate ions (HCO3)

Question 29

what reversible reaction does carbonic anhydrase catalyse

Answer 29

CO2+H2O = carbonic acid (H2CO3)

Question 30

what does chloride shift do

Answer 30

maintain electrical balance of the cell

Question 30

why is it good to convert CO2 into hydrogen carbonate ions (HCO3)

Answer 30

maintains steep concentration gradient for CO2 to diffuse from respiring tissues into erythrocyte

Question 31

what does carbonic acid break down into when it reaches the lungs

Answer 31

CO2 and H2O

Question 31

route of blood through the heart to lungs. chambers, vessels, valves

Answer 31

vena cava right atrium tricuspid valve open right ventricle tricuspid valve close semilunar valve pulmonary artery

Question 31

where is bicuspid valve

Answer 31

between left atrium and ventricle

Question 32

route of blood through the lungs to heart. chambers, vessels, valves

Answer 32

pulmonary vein left atrium bicuspid valve opens left ventricle semilunar valve bicuspid valve close aorta

Question 33

what does semilunar valves connect

Answer 33

ventricle and pulmonary vein/artery

Question 33

2 stages of the cardiac cycle

Answer 33

diastole and systole

Question 34

why does the left side of the heart have a thick muscular wall

Answer 34

has further to pump blood. body, lungs

Question 35

role of the septum

Answer 35

divides oxygenated and deoxygenated blood mixing

Question 35

do the left and right side of the heart fill and empty at the same or different times

Answer 35

same

Question 36

what happens in diastole

Answer 36

heart relaxes atria then ventricles fill with blood volume and pressure of blood increases as heart fills pressure in arteries is at minimum

Question 37

what happens in systole

Answer 37

atria contract ventricles contract pressure in heart increases blood forced out volume and pressure are low pressure in arteries maximum

Question 38

whats atrial systole

Answer 38

atria contract

Question 39

whats ventricular systole

Answer 39

ventricles contract

Question 40

how is heartbeat rhythm maintained

Answer 40

wave of electrical excitation occurs at the SAN - causes atria to contract electrical signal picked up by AVN - imposes a slight delay before stimulating the bundle of his bundle of his splits in 2 branches and conducts the wave of excitation to the bottom of the heart. purkyne fibres spread through the walls of the ventricles - spread of excitation triggers the contraction of the ventricles

Question 41

where is the SAN

Answer 41

right atrium

Question 41

what stops the electrical excitation at the SAN passing to the ventricles to make them contract

Answer 41

layer of non conducting tissue

Question 42

why is the delay at the AVN important

Answer 42

makes sure the atria have stopped contracting before the ventricle contract

Question 43

what does an ECG record

Answer 43

spread of electrical excitation through the heart

Question 44

4 heartbeat abnormalities, explain them and what happens to the ECG

Answer 44

tachycardia - fast HR. spikes closer together bradycardia - slow HR. spikes further apart ectopic heartbeat - extra heartbeats out of normal rhythm. altered rhythm followed by pause. big spikes Atrial Fibrillation - abnormal rhythm of heart. spikes random. can be gaps