(N/A) Blood is a specialized connective tissue consisting of a fluid matrix,plasma,and formed elements.
$1$. Plasma: It is a straw-colored,viscous fluid constituting nearly $55 \%$ of the blood. It contains water $(90-92 \%)$,proteins (fibrinogen,globulins,and albumins),glucose,amino acids,and lipids.
$2$. Formed Elements: These constitute nearly $45 \%$ of the blood and include:
- Erythrocytes $(RBCs)$: These are the most abundant cells in the blood,containing the red pigment hemoglobin,which transports $O_2$.
- Leucocytes $(WBCs)$: These are colorless cells that lack hemoglobin and are nucleated. They are responsible for the immune response of the body.
- Thrombocytes (Platelets): These are cell fragments produced from megakaryocytes. They play a crucial role in the blood coagulation process.