Mass Transport PPQs Flashcards
During the cardiac cycle changes in pressure cooker and the left atrium and left ventricle. Used graph and your own knowledge to explain these differences. (5)
(mp1) Difference: pressure changes in atrium are smaller than pressure changes in ventricles
Explanation:
(mp2) - bc atrium has less cardiac muscle than ventricles
(mp3) - because DOESNT have to pump blood as far as ventricles (to rest of body)
(mp4) Difference: atria increase in pressure before ventricles increase in pressure
Explanation:
(mp5) - atriole systole must happen before ventricular systole so ventricles can fill with blood
(mp6) - increase in atrial pressure caused increase in pressure in ventricles
mp7 - pressure in atrium larger than pressure in ventricle so atrioventricular valve opens preventing further significant increase in pressure in atrium
At which time does the valve between the atrium and ventricle close? (1)
0.10s
Thought process:
Ventricular pressure is rising
Ventricular pressure only rises once the atrioventricular valve has shut
So the valve must shut when the ventricular pressure starts rising
Which is at 0.10 seconds
To risk factors of coronary heart disease
Smoking
High blood cholesterol
Use information from the figure to explain how the pressure in the dogs ventricle is related to bloodflow
Pressure increases THEN blood flows into aorta
Because increasing pressure CAUSES semi lunar to open
Ventricle pressure starts to fall to blood flow to aorta starts to fall
Use information from the figure to explain how the pressure in the dogs ventricle relates to the thickness of the ventricle wall (2)
Thickness increases because the ventricle contracts
Contraption causes an increase in pressure
Explain the importance of maintaining a constant blood pH(3)
Hb affected by change in pH
Change to tertiary structure
Less oxygen binds to Hb
Although the speed of bloodflow in an arterial is greater than the speed of bloodflow in a capillary, large does not accumulate in the arterioles.
Explain why (1)
More capillaries an artériole
Area of capillaries is larger than the area of the artériole
Other than causing slow bloodflow explain one advantage of the capillaries being narrow (1)
Larger surface area of blood in contact with capillary walls
Short diffusionpathway (distance between blood and outside of capillaries)
What factor limits the minimal internal diameter of the lumen of a capillary?
Size of red blood cell
The volume of blood leaving the capillary network into the vein is less than the volume of blood entering from the arteries.
Explain why. (1)
Fluid from blood has been squeezed out to form tissue fluid
During a heart attack part of the heart muscle dies explain why (3)
Coronary arteries blocked
NOT ENOUGH oxygen reaches respiring cells
Respiration stops
The thickness of the iota wall changes all the time during the cardiac cycle. Explain why (3)
Aorta wall stretches because ventricle contracts
Aorta wall recoils because ventricle relaxes
To maintain blood pressure
Describe how tissue fluid is formed and how is returned to the circular Tory system (6)
X
Describe how haemoglobin on loads and loads oxygen in the body (3)
Loads at high partial pressures and has high affinity and is in LUNGS
Unloads at low partial pressures and has low affinity
Smaller mammals have
LARGER SA:V
What does a larger SA:V mean ??
More heat loss
Heat from respiration helps mammals to maintain a constant body temperature.
Useless information to explain the relationship between the surface area to volume ratio of mammals and oxygen dissociation curve of the haemoglobins.
Small animals have larger SA:V so lose more heat
So have a greater rate of respiration
So Hb curves shifts right
Hb has lower affinity and lower partial pressures so easier unloading of oxygen to repairing cells
What is meant by the term partial pressure (1)
Measure of the concentration of the gas in a mixture of gases
Why is oxygen partial pressure at the tissues lower during exercise?
Increased oxygen consumption Lowes tissue partial pressure of oxygen
Does enriching inspired air with oxygen have any effect on the amount of oxygen reaching the tissues? Support your answer with evidence from the graph and table 2.
XXX
X
Give two ways in which the total oxygen supply to the muscles during exercise is increased. (3 ways)
Increased depth of pulmonary ventilation
Increased heart rate
Greater proportion of bloodflow to the muscles by arterioles dilating
Explain the role of the heart in the formation of tissue fluid. (2)
High hydrostatic pressure produced from ventricle contracting
Forces water out of the capillaries
Cause of lymphoedema
Excess tissue fluid builds up
The scientist concluded that treatment with hydroxyurea would increase the concentration of oxygen in the blood of babies with sickle-cell disease.
Suggest how the graph and the table above support this conclusion. (3)
After treatment mean concentration of HBF in the babies blood significantly increased
HBF has a higher affinity for oxygen
High proportion of HBF in the blood means more oxygen is carried
Explain how the changes in the shape of haemoglobin result in the sigmoid Oxy haemoglobin dissociation curve (2)
First oxygen binds to haemoglobin causing it to change shape
Allows other oxygen to bind more easily
Use the graph to explain why this change is an advantage for the baby (2)
HP a has a lower affinity for oxygen at low partial pressures
So easier unloading of oxygen for respiration
Explain for ways in which the structure of the aorta is related to its function (4)
Elastic tissues allows stretching
Smooth endothelium reduces friction
Musculaire all withstands high pressures
Aortic valve prevents back flow
Muscle for contraction
Elastic tissues stretches when ventricles contract
How many milliseconds in one second
1000
Explain how the heart muscle and the heart valves maintain a one-way flow of blood from the left atrium to the a water (5)
Atrial pressure exceeds ventricular pressure
Causing atrioventricular valve to open
Ventricular pressure exceeds atrium pressure
Causing atrioventricular valve to close
Ventricular pressure exceeds a water pressure
Causing semilunar valve to open
Aorta pressure exceeds ventricle pressure (as the heart relaxes)
Causing semilunar valve to close
Contraction causes an increase in pressure
Suggest where the left ventricle requires the help of the artificial heart but the right ventricle does not (2)
Left ventricle produces a greater pressure (must pump blood at higher pressure is)
Because it must pump blood to the WHOLE of the body
What do these data show about the effect of glycaemic load on the diet has on the risk of developing coronary heart disease ? (1)
No affect on risk in diet groups one and two
For diet group 2 and above increased risk of CHD as GL increases
Use the information provided to explain the effect that glycaemic load of the diet has on the risk of developing coronary heart disease (2)
For diet groups two and above, and increase risk of CHD as GL increase is because increase concentration of harmful lipids in the blood
So increased risk of atheroma
Atheroma leads to blockage of coronary artery
