1. Blood

2. Blood
Blood is a type of connective tissue that consists of formed elements (cells and cell fragments) surrounded by a liquid matrix.

3. Formed Elements
Red blood cells (RBCs) or erythrocytes account for about 95% of the volume of formed elements.
White blood cells (WBCs) or leukocytes and platelets or thrombocytes (cell fragments) account for the other 5%.

4. Erythrocytes (RBC)
Erythrocytes (RBCs) are disk-shaped cells that contain hemoglobin (responsible for red color).
The primary function of erythrocytes are
To transport oxygen from the lungs to the various tissues of the body
To assist in the transport of carbon dioxide from the tissues to the lungs.

5. Leukocytes (WBC)
Leukocytes (WBCs) are spherical cells that are a whitish color because they don’t have hemoglobin.
Leukocytes
Protect the body against invading microorganisms
Remove dead cells and debris from tissues

6. Platelets
Platelets, or thrombocytes, are fragments of cells that are produced in the red bone marrow.
Platelets are involved with preventing blood loss (important role in homeostasis).

7. Plasma Plasma is a pale yellow fluid that consists of : Plasma
92% water
8% substances (proteins, ions, nutrients, gases, and waste products)
Plasma
Maintains osmotic pressure
Is involved in immunity
Transports molecules

8. Blood Grouping
The surface of erythrocytes have molecules called antigens and in the plasma there are proteins called antibodies.
Antibodies are very specific – each antibody can only combine with a certain antigen.
The antigens have been categorized into blood groups.

9. ABO Blood Group Blood Type Type of Antigens present
Type of Antibodies Present A B AB
A and B
Neither A nor B O

10. Rh Blood Group Rh-positive blood has the Rh antigen
Rh-negative blood does not have the Rh antigen
Antibodies against the Rh antigen do not develop unless an Rh-negative person is exposed to Rh-positive blood.
Can occur through a transfusion
Can occur through transfer of blood across the placenta

11. Blood Video