Biology - 2.2 Transportation Animals

Question 1

Atrial Systole

Answer 1

Both atria contract pushing blood to ventricles
Cuspid valves open
Ventricles in diastole
Vena cava and pulmonary vein sealed off
Semi lunar valves are closed

Question 2

Ventricular Systole

Answer 2

Atria in diastole
Ventricles contract pushing blood into arteries
Cuspid valves shut
Semi lunar valves open allowing blood to leave

Question 2

Diastole

Answer 2

Both atria and ventricles relaxed
Blood flows into heart via vena cava and pulmonary vein
Semi lunar valves shut
Heart refills with blood

Question 2

A on pressure diagram

Answer 2

Atrioventricular valves closing, Ventricular pressure increases to more than atrial pressure
Ventricles contracting

Question 3

B on pressure diagram

Answer 3

Semilunar valves are opened
Aortic pressure increases but slightly lower than ventricular

Question 4

C on pressure diagram

Answer 4

Semilunar valves closing
Ventricular pressure much lower than aorta pressure

Question 5

D on pressure diagram

Answer 5

Atrioventricular valves open
Aortic pressure slightly more than ventricular pressure

Question 6

Lub

Answer 6

Closure of cuspid valves - ventricular systole

Question 7

Dub

Answer 7

Closure of semilunar valves - atrial systole

Question 8

Events at QRS complex

Answer 8

Atrioventricular node transmits electrical impulses through bundles of HIS and Purkinje fibres
Ventricles depolarise
Ventricular systole

Question 9

Events at P wave

Answer 9

Sinoatrial node generates electrical impulse
Impulse causes atria to depolarise
Atria contracts (atrial systole)

Question 10

Events at T wave

Answer 10

Sinoatrial node generates electrical impulse
Impulse causes ventricles to repolarise
Ventricular diastole takes place

Question 11

How would distance between P waves would differ if a person takes exercise?

Answer 11

Lengths of P wave would be shorter
Less time between ventricular and atrial systole

Question 12

Effect of first degree heart block on functioning heart

Answer 12

Slower heart beat

Question 13

How many molecules of 02 in oxyhemoglobin?

Answer 13

4

Question 14

Why is flat top advantageous in association curve?

Answer 14

If partial pressure is reduced most haemoglobin would still be highly saturated with oxygen

Question 15

Why is steepness of association curve advantageous?

Answer 15

A small increase in oxygen tension leads to a large increase in saturation

Question 16

Myoglobin

Answer 16

Can bind to one molecule of o2, delays anaerobic respiration, takes low pressure for myoglobin to let go

Question 17

Bohr Shift

Answer 17

Shift to the right
Higher CO2 production
More shift = more oxygen is released to be used in aerobic respiration

Question 18

What happens when respiration rates are high?

Answer 18

More CO2 produced by cells
More CO2 diffuses into red blood cells
More carbonic acid formed
More H+ ions formed = more disassociation at higher partial pressure

Question 19

Chloride Shift

Answer 19

1. Co2 diffuses into red blood cell
2. Co2+H2O+carbonic anhydrase = carbonic acid
3. Carbonic acid dissociated into H+ and HCO3- ions
4. CL- ions facilitated diffuse into RBC to maintain electrochemical neutrality
5. H+ binds to oxhaemoglobin reducing its affinity to oxygen
6. O2 released and diffuses into plasma

Question 20

Structure of artery

Answer 20

Tough collagen outer coat to prevent overstretching
Small lumen to prevent friction
Thick layer of smooth muscle that recoils to maintain blood pressure

Question 21

Structure of vein

Answer 21

Larger lumen as blood is under lower pressure
Semilunar valves to prevent back flow of blood