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 the 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 an antigen.
- The antigen is of two types- Antigen A and Antigen B.
- On the basis of the presence of Antigen or Glyco Protein, there is four groups 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 an 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 anticoagulant that is present in the blood which assures smooth blood flow in the vessels.
Most Important Study Notes
Free मे पढ़े GS/GK Study Notes और अपनी तैयारी को मज़बूत करे
Comments
write a comment