Circulation Flashcards
What is a double circulatory system?
It is where blood is oxygenated in the lungs and pumped everywhere in the body to provide oxygen to the muscles. The blood that returns will be de oxygenated and returns back from muscles to the heart and lungs.
What are the components of blood.
Red blood cells.
White blood cells.
Platelets.
Plasma.
What are the various functions of the components of blood?
Red blood cells transport oxygen. White blood cells fight infections. Platelets cause blood clots at injury sites to stop bleeding. Plasma transports nutrients, antibodies, hormones and waste through the blood.
How have red blood cells adapted for their specific function?
Packed with haemoglobin to maximise oxygen binding. They have no nucleus to allow space for more haemoglobin. A biconcave shape increases surface area for oxygen exchange.
How is the heart structured?
There are left and right atria and ventricles that are the main chambers where all the blood passes through. The vena cava is the main vein that takes in deoxygenated blood from the body. The aorta takes oxygenated blood from the heart to the body. The pulmonary vein and artery take blood to and from the lungs and heart to keep blood oxygenated.
Where are valves found and what is their purpose?
They are in the heart and veins, they ensure that blood cannot flow back on itself where it is not under high pressure.
How is tissue fluid formed?
Gas exchange occurs in capillaries, which are far thinner than veins and arteries, this means that the liquid plasma is squeezed out into the spaces between, the capillary beds.
How does gas exchange occur?
Once the plasma is squeezed out, the dissolved glucose and oxygen can diffuse back into the cells and the waste products like urea and CO2 can diffuse out and then back into the blood that will take it away from muscles.
