More Exchange & Transport Topic-3B Flashcards
Why is the circulatory system of mammals referred to as a double circulatory system?
There are two circuits, one taking blood from the heart to lungs and one back to the heart then to the rest of the body.
Name the part of the heart that provides it with its own blood supply.
The coronary arteries
Why are the pulmonary vein and artery different from usual?
As the vein carries oxygenated blood and the artery carries deoxygenated blood.
What does the aorta do?
Supplies oxygenated blood to the body
What does the vena cava do?
Supplies deoxygenated blood to the heart.
The ……. vein and …….. artery can be associated with the kidneys.
The renal vein and renal artery can be associated with the kidneys.
The hepatic vein and artery are associated with…?
The liver and gut
The hepatic portal vein can be found….
Between the liver and the gut.
Name adaptations of arteries
Walls are THICK and MUSCULAR
Walls have ELASTIC tissue to STRETCH and recoil as the heart beats (MAINTAINS HIGH PRESSURE)
endothelium is FOLDED allowing it to stretch.
Name the role of arteries
Arteries carry blood from the heart to the rest of the body.
Name the adaptations of veins
Wider lumen than arteries, have very little elastic or muscle tissue.
Valves to prevent backflow
Name the roles of veins
Take blood back to the heart under low pressure.
Name the roles of capillaries
Substances are exchanged between blood and body tissue at the capillaries.
Name adaptations of capillaries.
Found very near cells in exchange tissues (short diffusion pathway)
Walls only one cell thick
Large number to increase surface area (capillary beds=a network of capillaries in tissue.
What is tissue fluid?
The fluid that surrounds cells in tissues, made from small molecules that leave blood plasma(O2)
Name factors that increase the risk of cardiovascular disease.
High blood cholesterol and poor diet
Cigarette smoking
high blood pressure
genetic factors
Name the main stages of the cardiac cycle
Ventricles relax, atria contract
Ventricles contract, atria relax
Ventricles and atria relax
Name the main stages of the cardiac cycle in order
Ventricles relax, atria contract
Ventricles contract, atria relax
Ventricles and atria relax
How does blood get pushed into the ventricles?
The pressure increase due to volume decrease in the atria pushes the blood into the ventricles.
What happens when the pressure in the ventricles becomes higher than the atria?
The atrioventricular valves are forced shut and due to pressure in ventricles being higher than pulmonary artery and aorta the semi-lunar valves are forced open.
Why does the left ventricle have thicker muscular walls than the right ventricle?
Because it needs to contract powerfully to pump blood all the way round the body, not just to nearby lungs.
Why do the ventricles have thicker walls than the atria?
Because they have to push blood out of the heart but the atria just push blood a short distance into the ventricles.
Give the equation to calculate stroke volume
Stroke volume= cardiac output/heart rate
Give 4 ways the aorta structure is related to its function
Thick walls to withstand high pressure
Elastic tissue to allow recoil
Muscle for contraction
Semi-lunar valves to prevent backflow of blood.
Explain how tissue fluid is formed.
The overall hydrostatic pressure inside capillary is more than outside so small molecules are forced out of the capillary =tissue fluid.
Why does the hydrostatic pressure fall from the arteriole end to the venule end of the capillary?
Due to the loss of fluid through the capillary lining.
How does high blood pressure lead to an accumulation of tissue fluid?
High blood pressure=high hydrostatic pressure
Increases outward pressure of arterial end of capillary so more tissue fluid is formed.
Why is the water potential of the blood plasma more negative at the venule end than the arteriole end of the capillary?
Water has left capillary but the proteins in the blood are too large to leave so the concentration of blood proteins is higher and thus water potential.
Why would something be described as processed results?
Due to calculations being made from raw data
How would you use given data to find water potential?
Plot graph with conc on x axis and % change in mass on y axis.
Find where the curve crosses x axis
use calibration table to find wp of sucrose concentration.
Oxygen loads onto haemoglobin to form oxyhaemoglobin where there’s ….. ……
High pO2
pO2 means….
Partial pressure of oxygen