Transport In Animals

Question 1

what is the pulmonary circulatory system

Answer 1

when blood is pumped from the right ventricle to the lungs and returns back to the heart

Question 2

what is the systemic circulatory system

Answer 2

when blood is pumped from the left ventricle to the rest of the body

Question 3

name the vessels in the liver

Answer 3

hepatic vein
hepatic artery
hepatic portal vein

Question 4

name the vessels in the kidney

Answer 4

renal vein
renal artery

Question 5

where do the coronary arteries branch off from

Answer 5

coronary arteries branch off from the aorta and supply oxygen and glucose to the heart muscle

Question 6

what is the double circulatory system in mammals

Answer 6

blood is pumped from the heart via the right ventricle to the lungs and then returns to the heart (pulmonary circulatory system ) before being pumped via the left ventricle to the rest of the body (systemic circulatory system)

Question 7

what is the equation for cardiac output
cm3 min-1

Answer 7

cardiac output = stroke volume x heart rate

Question 8

what is the definition for cardiac output

Answer 8

cardiac output is the volume of blood expelled from the left ventricle in 1 minute

Question 9

what’s the definition stroke volume

Answer 9

stroke volume is the volume of blood expelled from the left ventricle of the heart per contraction

Question 10

what is the definition of heart rate

Answer 10

the number of contractions of the heart per minute

Question 11

what happens to the heart during excercise

Answer 11

during exercise, the rate at which venous blood returns to the heart increases. this increased blood flow causes the cardiac muscle to contract more strongly , pumping out an increased volume of blood (stroke volume increases) . the heart rate also increases during exercise

Question 12

what happens to the heart when you regularly exercise

Answer 12

regular exercise causes the heart to produce stronger contractions and the ventricles to be larger in size and volume. this leads to an increased stroke volume and in tern a reduction in the resting heart rate

Question 13

what is a risk factor

Answer 13

anything that increases the chance of getting a disease
eg smoking

Question 14

what is oxygen carried in

Answer 14

the respiratory pigment “haemoglobin” in red blood cells

Question 15

what is haemoglobin

Answer 15

haemoglobin is a iron containing pigment which loosely and reversibly combines with oxygen to form oxyhaemoglobin

Question 16

what does each haemoglobin molecule consist of

Answer 16

haemoglobin molecule consists of 4 polypeptide chains with 4 haem units

it is a quaternary structure as it has more than one polypeptide chain

Question 17

what affinity for oxygen does haemoglobin have in the lungs and why

Answer 17

haemoglobin has a high affinity for oxygen in the lungs as there is a high partial pressure of oxygen and so it quickly loads oxygen and becomes mostly saturated

Question 18

what affinity for oxygen does haemoglobin have in body tissues

Answer 18

haemoglobin has a low affinity for oxygen in the body tissues at low partial pressures , haemoglobin unloads some of its oxygen at respiring cells

Question 19

what shape is the oxyhaemoglobin disassociation curve

Answer 19

a s shape (sigmoid)

Question 20

why is the oxyhaemoglobin disassociation curve a sigmoid shape

Answer 20

because when a molecule of oxygen binds to one of four haem units

this causes a change in the tertiary structures of the other haem units / quaternary structure of the haemoglobin

this increases their affinity for oxygen allowing the 2nd oxygen molecule to bind more easily etc and this is called CO-OPERATIVE BINDING

^ by the same process, the ability for haemoglobin to lose oxygen increases as fewer oxygen molecules are bound

Question 21

what is myoglobin

is it a store of oxygen

Answer 21

myoglobin is only present in muscles

it has a much higher affinity of oxygen that haemoglobin

myoglobin only releases oxygen when the partial pressure of oxygen is low in the tissues and haemoglobin has already unloaded most of its oxygen

yes haemoglobin is a store of oxygen in the muscle cells

Question 22

what is the bohr effect

Answer 22

the bohr effect only takes place in the tissues, usually during exercise

the bohr effect does not take place in the lungs

during exercise, muscle cells respire more rapidly producing a larger concentration of co2. and the co2 dissolves in the blood plasma to form an acid which decreases the pH

the change of pH in the tissues causes the quaternary structure of the haemoglobin to change and lowers the affinity of oxygen in haemoglobin

haemoglobin releases more oxygen to the respiring cells

the bohr effect is a physiological advantage to the body as it ensures haemoglobin releases more oxygen to the most active cells for the increase of respiration taking place

the oxygen disassociation curve shifts to the right

Question 23

what happens to haemoglobin for organisms who live in low concentrations of oxygen environments

where does the oxygen disassociation curve shift

Answer 23

the haemoglobin will have a higher affinity oxygen as it will load more oxygen at the low partial pressure of oxygen

the oxygen disassociation curve shifts to the left