Body Fluids and Circulation

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(b) Monocytes (6-8%) : Largest WBC.

Function: Phagocytosis.



Kupffer cells of Liver: Transformed monocytes, act as macrophages

PLÅTËLËTS (THRØMBØÇÝTËS) :

 Colourless non-nucleated cell fragments.

 Counts : 1.5 - 3.5 Lakhs/mm³.

 Formed in: Megakaryocytes in bone marrow.

 Average lifespan : 7 days.

 Function : Blood clotting.

BLOOD GROUPS

Blood

groups

were

discovered

by

Carl

Landsteiner.

Various

types

of

blood

grouping has been done. Two

such groupings are- ABO and

Rh. These are widely used all

over the world.

ÅBØ GRØÜPÏÑG



It is based on presence or absence of 2 surface antigens (chemicals

that induce immune response) on RBCs namely A & B. Similarly, plasma

contains 2 antibodies (proteins produced in response to antigens)

namely anti-A & anti-B.

Blood Group

Antigens on RBCs

Antibodies in Plasma

Donor’s Group

A

A

Anti -B

A, O

B

B

Anti -A

B, O

AB

A, B

Nil

AB,A,B,O

O

Nil

Anti-A, Anti - B

O



Antigen A reacts with anti-A, antigen B reacts with anti-B.



If bloods with interactive antigens & antibodies are

mixed together, it causes clumping (agglutination)

of RBCs.



Persons with O blood group are called universal

donors because they can donate blood to persons

with any other blood group. Persons with AB group

are called universal recipients because they can accept blood from all

groups. (AIPMT 2014)