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Notes for 1 biology blood fluid and transportation

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Answered by nehadav98
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Blood performs many important functions within the body, including:

Supply of oxygen to tissues (bound to hemoglobin, which is carried in red cells)Supply of nutrients such as glucose, amino acids, and fatty acids (dissolved in the blood or bound to plasma proteins (e.g., blood lipids))Removal of waste such as carbon dioxide, urea, and lactic acidImmunological functions, including circulation of white blood cells, and detection of foreign material by antibodiesCoagulation, the response to a broken blood vessel, the conversion of blood from a liquid to a semisolid gel to stop bleedingMessenger functions, including the transport of hormones and the signaling of tissue damageRegulation of core body temperatureHydraulic functions.
Answered by Anonymous
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11 Biology

Body Fluid Circulation

Blood:

Blood is a connective tissue which is composed of a fluid matrix (plasma) and formed elements.

Plasma: Plasma is a straw-coloured and viscous fluid. Plasma constitutes about 55% of the blood. About 90% of plasma is water and about 6-8% is composed of proteins. The major plasma proteins are; fibrinogen, globulins and albumins. Fibrinogen play important role in blood coagulation. Globulins are mainly involved in defense mechanism and albumins help in osmotic balance. Small amounts of minerals; like Na+, Ca++, Mg+ +, HCO3– and Cl–; are also present in plasma. Plasma also contains glucose, amino acids, lipids, etc. because these substances are always in transit in the body. Factors for clotting of blood are present in the plasma in an inactive form. Plasma without the clotting factors is called serum.

Formed Elements: The formed elements constitute about 45% of the blood. Erythrocytes, leucocytes and platelets are collectively called formed elements.



Erythrocytes or Red Blood Cells (RBCs):The RBCs are the most abundant cells in blood. In a healthy adult, about 5 million to 5.5 million RBCs are present per cubic mm of blood. RBCs are formed in the read bone marrow in adults. In most of the mammals, nucleus is absent in the RBCs. RBCs are biconcave in shape. The red colour is because of an iron containing protein complex; called haemoglobin. In a healthy adult, each 100 ml of blood contains 12-16 gm haemoglobin. The average lifespan of RBCs is 120 days. RBCs are finally destroyed in the spleen and hence, spleen is also called the graveyard of RBCs. RBCs play a significant role in transport of respiratory gases.

Leucocytes or White Blood Cells (WBCs):The WBCs are nucleated and are relatively lesser in number than RBCs. In a healthy adult about 6000-8000 WBCs are present per cubic mm of blood. Leucocytes are generally short lived.

There are two main categories of WBCs:

Granulocytes , e.g., neutrophils, eosinophils and basophils

Agranulocytes. e.g., Lymphocytes and monocytes.

Neutrophils: Neutrophils are the most abundant cells among WBCs and comprise about 60-65%.

Monocytes: Monocytes comprise about 6-8% of WBCs. Neutrophils and monocytes are phagocytic cells.

Basophils: Basophils secrete histamine, serotonin, heparin, etc. They are involved in inflammatory reactions.

Eosinophils: Eosinophils comprise 2-3% of WBCs. These resist infections and are also associated with allergic reactions.

Lymphocytes: Lymphocytes comprise about 20-25% of WBCs. There are two major types of lymphocytes, viz. B and T types. Both the types are responsible for immune responses of the body.

Platelets: Platelets are also known as thrombocytes. They are cell fragments produced from megakaryotcytes. Megakaryocytes are special cells in the bone marrow. Usually, one cubic mm of blood contains 150,000-350,000 platelets. Platelets can release a variety of substances. Most of these substances are involved in blood coagulation.

BLOOD GROUPS

Two such groupings – the ABO and Rh – are widely used all over the world.

ABO Grouping

ABO grouping is based on the presence of absence of two surface antigens on the RBCs, viz. A and B. Antigens are chemicals which can induce immune response. The plasma also contains two natural antibodies. Antibodies are proteins produced in response to antigens.

Importance of Blood Group: During blood transfusion, the donor blood needs to be carefully matched with the blood of a recipient. Transfusion of unmatched blood can lead to severe problems of clumping, i.e. destruction of RBC.

Blood Groups and Donor CompatibilityBlood GroupsAntigen on RBCAntibodies in PlasmaDonor’s GroupAAAnti-BA, OBBAnti-AB, OABABNilAB, OOOAnti-A, BO
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