animal transport

Question 1

what is a singular circulatory system?

Answer 1

blood passes through the heart once for each complete circuit of the body

Question 2

what is a double circulatory system?

Answer 2

blood passes through the heart twice for each complete circuit of the body

Question 3

what is a closed circulatory system?

Answer 3

blood enclosed in blood vessels all the time

Question 4

what is an open circulatory system?

Answer 4

blood isn’t enclosed within vessels all the time

Question 5

what is the systemic and pulmonary circuit?

Answer 5

systemic- circuit where blood is sent to rest of body
pulmonary- circuit where blood is sent to lungs

Question 6

where do arteries carry blood to?

Answer 6

away from the heart

Question 7

how are arteries adapted to their function?

Answer 7

thick, muscular walls, with elastic tissue- to stretch and recoil, to maintain high pressure
endothelium is folded- maintain high pressure

Question 8

what are arterioles and how are they adapted?

Answer 8

arteries branch into arterioles
layer of smooth muscle allows them to expand and contract, controlling amount of blood flowing into tissue

Question 9

what do capillaries do?

Answer 9

exchange substances between blood and body’s cells

Question 10

how are capillaries adapted?

Answer 10

-branch to increase surface area
-thin walls (one cell thick) for short diffusion pathway
-narrow lumen to squeeze O2 molecules to release oxygen

Question 11

what are venules?

Answer 11

connected to veins, thin with muscle cells

Question 12

where do veins carry blood to?

Answer 12

back to heart

Question 13

adaptations of veins?

Answer 13

wide lumen
valves to prevent backflow of blood
body muscles around vein contract to help blood flow
little elastic/ muscle tissue- low pressure

Question 14

order of blood vessels at top of heart from left to right?

Answer 14

vena cava
pulmonary artery
aorta
pulmonary vein

Question 15

what do atrioventricular valves link, and where is it located?

Answer 15

link atria to ventricles
located between right atrium and ventricle

Question 16

what do semilunar valves link and where is it located?

Answer 16

link ventricles to pulmonary artery and aorta
located between left and right atrium

Question 17

What is tissue fluid made from?

Answer 17

Substances that leave blood plasma e.g oxygen, water, nutrients

Question 18

Why doesn’t tissue fluid contain RBC or plasma proteins?

Answer 18

They are too large to leave capillary through capillary wall

Question 19

How is fluid forced out of capillary artery end?

Answer 19

Hydrostatic pressure inside capillary is greater than in tissue fluid

Question 20

How is oncotic pressure formed?

Answer 20

A water leave’s capillary, water potential decreases, plasma proteins generate oncotic pressure

Question 21

Why does water re enter capillary at venue end?

Answer 21

Water potential in capillaries is lower than in tissue fluid at venule end
Oncotic pressure greater than hydrostatic pressure at venule end

Question 22

What is the lymphatic system made up of?

Answer 22

Extra fluid that doesn’t re enter capillary returns to blood through lymphatic system
Made of lymph vessels

Question 23

How is pressure altered in atria and ventricles?

Answer 23

Contraction and relaxation of chambers, leading to change in volume and pressure

Question 24

What happens at start of cardiac cycle?

Answer 24

Atria contract, increasing pressure
Blood pushes into ventricles through atrioventricular valves

Question 25

What happens after blood enters ventricles?

Answer 25

Atria relax Ventricles contract, increasing pressure Pressure higher in ventricles than atria Atrioventricular valves shut to prevent back flow Ventricular pressure higher than arteries, semilunar valves open, blood forced into arteries

Question 26

What is third step of cardiac cycle? | diastole

Answer 26

Ventricles and atria relax (diastole) Semilunar valves close to prevent back flow, due to high pressure in arteries

Question 27

Cardiac output equation?

Answer 27

Cardiac output= heart rate x stroke volume

Question 28

Why is the heart myogenic?

Answer 28

It contracts and relaxes without receiving signals from nerves

Question 29

Electrical activity of heart steps?

Answer 29

-sino atrial node sets rhythm by sending waves of electrical activity to atrial walls -right and left atria contract -non conductive collagen tissue prevents electrical wave from passing to ventricles -SAN passed electrical wave to atrioventricular node -AVN passes electrical wave to bundle of His -passed along purkyne fibres, - passes electrical wave along ventricle walls, contraction from bottom up

Question 30

What does ECG stand for

Answer 30

Electrocardiogram trace

Question 31

What is the QRS complex

Answer 31

Contraction of ventricles

Question 32

What is the P wave, at start of trace?

Answer 32

Atrial contraction

Question 33

What is the T wave, at end of trace?

Answer 33

Relaxation of atria and ventricles

Question 34

What is tachycardia?

Answer 34

When the heartbeat is too fast

Question 35

What is bradycardia?

Answer 35

Heart beats too slowly

Question 36

What is ectopic heartbeat?

Answer 36

An extra heartbeat that interrupts rhythm (early ventricular or atrial contraction)

Question 37

What is fibrillation?

Answer 37

An irregular heartbeat

Question 38

Haemoglobin structure?

Answer 38

Four polypeptide chains Haem group on each chain, containing iron (red) Quaternary structure

Question 39

How many molecules/ atoms of oxygen can one haemoglobin molecule carry?

Answer 39

4 oxygen molecules 8 oxygen atoms

Question 40

What is the process where oxygen is joined to/ leaves haemoglobin?

Answer 40

Join to- association/ loading Leaves- dissociation/ unloading

Question 41

What is affinity for oxygen?

Answer 41

The tendency a molecule has to bind with oxygen

Question 42

What is pO2

Answer 42

Partial pressure of oxygen (Measurement of oxygen concentration)

Question 43

How do haemoglobin affinity for oxygen affected with pO2?

Answer 43

Higher pO2- higher affinity for oxygen

Question 44

At what pO2 does oxyhaemoglobin unload oxygen?

Answer 44

At a low pO2

Question 45

What is an oxygen dissociation curve?

Answer 45

How saturated haemoglobin is with oxygen at any given partial pressure

Question 46

How is ‘s’ shape formed on dissociation curve?

Answer 46

When haemoglobin combined with first O2 molecule, it changes shape to make loading of next easier As haemoglobin becomes saturated, it’s harder for oxygen molecules to join

Question 47

How to adult and feral haemoglobin differ?

Answer 47

Feral haemoglobin has a higher affinity for oxygen

Question 48

What happens at placenta?

Answer 48

Placenta has low pO2 Adult haemoglobin unloads oxygen Fetal haemoglobin loads oxygen at low pO2

Question 49

Where is fetal haemoglobin curve compared to adult?

Answer 49

To the left

Question 50

What is the Bohr effect?

Answer 50

-As cells respire, they release CO2, raising pCO2 -Rate or oxygen unloading increases -Dissociation curve shifts to right -Saturation of blood with oxygen is lower at a given pO2, so more oxygen is released

Question 51

How does pCO2 affect pO2?

Answer 51

-CO2 from respiring cells enters RBC -CO2 reacts with water to form carbonic acid -Catalysed by carbonic anhydrase -10% CO2 binds to haemoglobin to be carried to lungs -carbonic acid dissociates inro H+ and HCO3-

Question 52

Equation for CO2 reaction in red blood cells?

Answer 52

CO2 + H2O —-> H2CO3—> H+ + HCO3- Catalysed by carbonic anhydrase

Question 53

How is haemoglobonic acid formed?

Answer 53

Increase in H+ causes oxyhaemoglobin to unload oxygen, load H+ ions

Question 54

Why is haemoglobonic acid formed?

Answer 54

To stop H+ ions increasing cells acidity

Question 55

What happens to HCO3- ions formed from carbonic acid?

Answer 55

Diffuse out of red blood cells, transported by blood plasma

Question 56

What is the chloride shift?

Answer 56

Cl- ions diffuse into red blood cells to compensate for loss of HCO3- Maintains balance of charge between RBC and plasma