BLOOD Flashcards
Approx how much blood does a normal adult have?
It depends on weight but normally between 8 and 12 pints. Approx 1 pint per stone or .5 L per 7kg. This rule is very approximate and does not apply to persons who are obese. Babies may have as little as 1 pint of blood.
What does blood contain?
Blood is 60% Plasma which is a clear yellow fluid in which other cells and elements are suspended. Plasma is 90% water. A small amount of oxygen is also carried by the plasma, around 3% of the total oxygen..
RED blood cells contain a protein called haemoglobin which carry oxygen to the cells.
White cells help fight infection. Hospitals may test blood to measure the white cell count to confirm infection.
Platelets trigger a complicated chemical reaction if a blood vessel is damaged.
Nutrients and vitamins from the breakdown of food in the digestive system.
Carbon dioxide in the form of carbonic acid which is a waste product.
Heat, the blood circulates heat which is generated mostly by the liver.
Hormones
Antibodies
Where are blood cells produced?
In the bone marrow. The production of cells changes as we get older with less bones producing cells.
How are the production of red blood cells regulated?
Red blood cell production are regulated by a hormone called erythropoietin EPO and low oxygen levels. Conditions such as lung disease result in increased erythropoietin levels which in turn stimulate production of red blood cells
Blood is pumped via the heart through blood vessels. Can you name and describe the vessels?
Arteries mainly carry blood away from the heart via the main artery the aorta and descending aorta. They have strong elastic walls which can expand as blood pumped through the heart surges through.
Veins mainly carry blood towards the heart. They have thinner walls than arteries because blood in them is under less pressure. They have one way valves to keep blood flowing towards the heart. The main veins are the vena cava and inferior vena cava.
Capillaries are the tiny blood vessels which form a network between the veins and arteries which allow the transfer of gasses and nutrients between cells.
