Blood

• Blood is a fluid connective tissue.
• Its quantity is 6.8 litres in man and 500 ml less in woman.
• Constitutes 6-8% of body weight and has a pH of 7.4.

Blood Cells

They are of 3 types:

Red Blood Corpuscles (RBCs)

• Manufactured in Red Bone Marrow.
• Life is of 120 days.
• No. of RBCs is 4.5-5 millions/cubic mm of blood.

White Blood Corpuscles (WBCs)

• Manufactured in Red Bone Marrow.
• Act as a soldier of body's defence system.

Platelets

• Manufactured in Red Bone Marrow.
• Help the blood to clot.

Blood Grouping

• Father of Blood Grouping : Karl Landsteiner
• He discovered A,B and O blood groups.

BLOOD GROUP	CAN DONATE TO	CAN RECEIVE FROM
A	A, AB	A, O
B	B, AB	B, O
AB	AB	A, B, AB, O
O	A, B, AB, O	O

RH Factor

• It is a blood antigen found in RBC.
• Blood Transfusion technique was developed by  James Blundell.
• A person can be Rh+ or Rh- depending upon the presence of Rh factor in RBC.