BLOOD
Blood is specialized red fluid that is circulated by the heart through the vertebrate circualtory system
Blood makes up about 8% of the body mass of a mammal.
The average man has 4-6 l of blood circulating around the body
Function of the blood :
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keep the homeostasis
ability of clotting
transportation of oxygen from the lungs to the tissue cells
transportation of carbon dioxide from the tissue to the lungs
transportation of nutrients to the cells
conveyance of metabolit wastes from the cells to the organs of excretion( kidneys, lungs, liver … )
distribution of heat to all the body
Blood is composed of :
a) plasma
b) blood cells
PLASMA
Plasma is a pale yellowish fluid with a total volume of 2-3 liters in a normal adult.
It makes up about 55% of total blood volume.
Water
Proteins
Inorganic Ions
Organic Substances
90.0%
7-8.0%
1,00%
1,00%
Inorganic ions:
Sodium
Potassium
Calcium
Chloride
Hydrogen Carbonate
Phosphate
Na+
K+
Ca2+
ClHCO3PO43-
0,9% solution of natrium chloride is isotonic to blood plasm of human
Function of inorganic ions :
Keep pH value ( pH = 7,4 )
Important for osmotic pressure ( 0,9% solution of natrium chloride is isotonic to blood plasma of human)
Organic substances :
a) dissolved proteins : albumin : help to draw the water from tissues into blood
globulins : ( immunoglobulins ) : impotant for immunity
fibrinogen : participate in blood clotting
b) glucose : important as energy store ( normal blood glucose level is 4,4 – 5,5 mmol/ l)
c) other substances : amino acids, vitamins, hormones, waste products , lipids,…...........
BLOOD CELLS
ERYTROCYTES :
Structure: Erythrocytes are flat, round, nuclear-free (in mammals)cells,that are thin in the middle
Red blood cells includes hemoglobin.
Hemoglobin contain polypeptide chains and heme. Heme has porfyrin structure with the iron in the middle.
Erythropoesis : Erythropoesis is the formation of red blood cells in the bone marrow or in the liver and the spleen of fetus.For
the production of red blood cells is necessary to iron, vitamin B12 and erythropoetin.
Length of life : Red blood cells live 120 days and then disappear in the spleen
Number :
women : 3,8 – 4,8 mil./ml
men : 4,5 – 5,5 mil./ml
The number increases with altitude. Neonates have 7 mil. / ml
LEUKOCYTES :
Leukocytes are cells with a nucleus, have a different shape, sometimes unstable
Number :
5000 – 8000/ml
Types of leucocytes :
a) Agranulocytes :
Monocytes : Monocytes are the largest, have the ability fagocytosy
Lymfocytes : Lymphocytes have the ability to recognize a foreign antigen and proliferate in the blood
There are two types of lymphcytes : lymphocytes B and lymphocytes T
b) Granulocytes
Neutrofil : Neutrofil granulocytes are the most numerous and they can move freely around the body.
They have the ability fagocytosy
Bazofil : These leukocytes contain heparin
Eosinofil : Their number increases during allergic reactions or parasite infestation
THROMBOCYTES
Platelets are nepravidleného tvru bodies that have no nucleus.
They formed in the bone marrow from the megacaryocytes.
Number : 200 000 – 300 000/ ml
Function : Thrombocytes have a key role in blood clotting