animal transport

Question 1

features of artery

Answer 1

thick walls with muscle and elastic fibres to withstand high pressure
carries blood away from heart
smooth epithelial layer inside
narrow lumen
collagen

Question 2

features of veins

Answer 2

tunica externa - collagen
tunica media - elastic fibres and thin muscle
tunica interna - epithelial layer
wide lumen
carries blood towards heart low pressure
valves to stop backflow

Question 3

features of capillaries

Answer 3

wall one cell thick
red blood cells in lumen
endothelial cells

Question 4

open circulatory system

Answer 4

• haemolymph is blood in insects and invertebrates
• in insects it carries substances around body
• very inefficient in comparison to closed circulatory systems
• very low blood pressure means it cannot be redirected

Question 5

single circulatory system

Answer 5

• blood passes through the heart once in a complete circuit
• less efficient than double but still efficient
• low BP means less activity as less oxygen and glucose at cells
• fish relatively efficient so can be more active

Question 6

double circulatory system

Answer 6

• blood passes through twice in a complete circuit
• very efficient process
• maintains temperature

Question 7

right side of the heart

Answer 7

vena cava
right atrium
atrioventricular valve
semi lunar valve
right ventricle
pulmonary artery

Question 8

left side of the heart

Answer 8

aorta
pulmonary vein
left atrium
semi lunar valve
atrioventricular valve
left ventricle

Question 9

diastole meaning

Answer 9

ventricles relax, AV valves open, SL valves closed

Question 10

systole meaning

Answer 10

ventricles contract, AV closed, SL open

Question 11

cardiac cycle

Answer 11

1. low BP as blood flows into atrium and ventricle through veins
2. blood flows into left ventricle, AV closes (lub)
3. SLV opens
4. SLV closes (dub) ventricle relaxes, aorta no longer pumped into so pressure decrease
5. AV opens atrium and ventricle increase as fill with blood again

Question 12

myogenic meaning

Answer 12

involuntary muscle contraction, own intrinsic rhythm

Question 13

sinoatrial node meaning

Answer 13

pacemaker of heart coordinates heart contractions

Question 14

atrioventricular node meaning

Answer 14

picks up electrical activity from SAN and delays it

Question 15

bundle of his meaning

Answer 15

conducting tissue made of fibres splits into two branches and conducts wave of excitation to bottom of heart

Question 16

purkyne fibres meaning

Answer 16

spread out at apex, carry electrical signal and cause contraction at apex

Question 17

steps of control of heartbeat

Answer 17

1. wave of electrical excitation begins in SAN causing atria to contract and initiates heartbeat
2. detected by AV node which causes delay so atriums can contract and then stimulate bundle of his
3. signal travels down bundle of his through non-conductive septum
4. beach into 2 at apex and conducts wave of excitation to bottom of heart
5. at apex purkyne fibres spread out through walls of ventricles, contracts septum to allow more efficient emptying

Question 18

p

Answer 18

SAN causing atriums to contract

Question 19

QRS

Answer 19

electrical impulse that causes ventricles to contract

Question 20

U

Answer 20

not sure

Question 20

T

Answer 20

ventricles relax (repolarisation)

Question 21

bradycardic

Answer 21

BPM too low

Question 22

atrial fibrillation

Answer 22

atria contracting repeatedly (QRS very high, rest low)

Question 22

ectopic heartbeat

Answer 22

BPM irregular

Question 23

arteriole

Answer 23

more oxygen and glucose less carbon dioxide high hydrostatic pressure -4.2kPa oncotic pressure - 3.3kPa substances move out as high hydrostatic pressure overall - 0.9kPa

Question 24

venule

Answer 24

less oxygen and glucose more carbon dioxide low hydrostatic pressure - 2.3kPa oncotic pressure - 3.3 kPa substances move in as low hydrostatic pressure overall - 1kPa

Question 25

foetal haemoglobin

Answer 25

higher affinity for oxygen at given partial pressure to maternal so oxygen moves from mothers RBC to foetus

Question 26

myoglobin

Answer 26

found in muscles, very red

Question 27

formation of hydrogen carbonate ions HCO3-

Answer 27

HbO8 -> 4O2 + Hb oxygen dissociate from oxyhaemoglobin and diffuse from RBC into tissue fluis then into respiring body cells carbon dioxide from respiration diffuses out cells into TF then into RBC and react with H2O to form H2CO3 carbonic acid with help of carbonic anhydrase carbonic acid dissociated into H+ and HCO3- H+ ions mopped up by haemoglobonic acid H+ ions replace oxygen on oxyhaemoglobin HCO3- diffuse out and replaced by Cl- moving in