Human Blood
- The
blood constitutes 7%
of the total weight of the human's body.
- Its pH
value is nearly 7.4, so it is considered base in nature.
- There
is an average of 5-6
litres of blood in human body.
- Blood
consists of two parts:-
(1) Plasma
(2) Blood Corpuscles
(1) Plasma
- It
is the liquid part of
blood.
- It
constitutes 60% part of the blood.
- The
plasma has 90% parts is water, 7% protein, 0.9% salt and 0.1% is
glucose.
- Its
main function is to Transport of digested food, hormones, the excretory
product from one part of the body to another part of the body.
- When
Fibrinogen & Protein is extracted out of plasma, the remaining plasma
is called serum.
(2) Blood Corpuscles
- It
constitutes 40% part
of the blood/
This is divided into three
parts:
1.Red Blood Corpuscles (RBC)
- The
nucleus is absent from it. Exception - Camel and Lama.
- It
is formed in Bone Marrow (At the embryonic stage its formation takes place
in the liver.)
- Lifespan-
20 days to 120 days.
- RBCs
destruction takes place in spleen so it is called grave of RBC.
- It
contains haemoglobin, in which haeme is iron-containing
compound.
- Due
to the presence of haemoglobin colour of blood is red.
- Globin
is a proteinous compound which is extremely capable of combining with
oxygen and carbon dioxide.
- The
iron compound found in haemoglobin is haematin.
- Function-
to carry oxygen to all cells of the body and bring back the carbon
dioxide.
- Anaemia
disease is caused due to the deficiency of haemoglobin.
- At
the time of sleeping RBC is reduced by 5% and people who are at the height
of 4200 metres RBC increases by 30% in them.
2. White Blood Corpuscles
(WBC) or Leucocytes
- Its
formation takes place in Bone Marrow, lymph node and sometimes in liver
and spleen.
- Lifespan:
5-20 days.
- The
nucleus is present in the WBC.
- Function-
to protect the body from the disease.
- The
ratio of RBC and WBC is 600:1.
- It
consists of Granulocytes and Agranulocytes.
- Granulocytes
consists of Neutrophils, Eosinophils, and Basophils.
- Agranulocytes
consists of lymphocytes and
monocytes.
3. Blood Platelets
or Thrombocytes
- Found
only in the blood of human and other mammals.
- The
nucleus is absent in it.
- Its
formation takes place in the Bone marrow.
- Lifespan- 3 to 5 days.
- It
dies in the Spleen.
- Function-
to help in clotting of blood
Functions of Blood:
- To
control the temperature of the body and to protect the body from diseases.
- Transportation
of oxygen, Carbon dioxide, digested food, conduction of hormones etc.
- To
help in establishing coordination among different parts.
Clotting of blood
- Following
reactions take place during clotting-
(a) Thromboplastin + Prothrombin + Calcium = Thrombin
(b) Thrombin + Fibrinogen = Fibrin
(c) Fibrin + Blood Corpuscles = Clot - Vitamin
K is helpful in blood clotting.
Blood Group of Human
- Blood
group was discovered by Landsteiner in
1900.
- For
this, he was awarded Nobel Prize in
the year 1930.
- The
main reason behind the difference in the blood of the human is the glycoprotein which is found
in Red Blood Corpuscles called antigen.
- Antigen
is of two types- Antigen A and Antigen B.
- On
the basis of the presence of Antigen or Glyco Protein, there is four group
of blood in human:
- That contains Antigen A - Blood Group
A.
- That contains Antigen B- Blood Group B.
- That
contains both the Antigen A and B - Blood Group AB.
- That
contains neither of the Antigens- Blood Group O.
- An
opposite type of protein is found in blood plasma. This is called
antibody. This is also of two types- Antibody "a" and Antibody
"b".
Blood Group O is called the Universal Donor because it does not contain any antigen.
Blood Group AB is called Universal Recipient because it does not contain any antibody - Heparin is an anti-coagulant which is
present in blood which assures smooth blood flow in the vessels.
No comments:
Post a Comment