Day: June 3, 2022

most important Tissues

Bone – it is hardest connective tissues its matrix is so much hard due to presence of salts, such as calcium phosphate, etc. it help in locomotion. It protect internal delicate organ.

Vascular tissues: it is the fluid tissues that form supportive frame work of body. It is of two types:

  1. Blood — Blood is a special connective tissue consisting of a fluid matrix, plasma, and formed elements.

Blood is a fluid connective tissue. Its cells are quite distinct from other connective tissue cells, both in structure and functions. The extracellular material in blood is a fluid devoid of fibers. Fluids outside the cells are generally called Extracellular Fluids (ECF).

The extracellular material in blood is a straw-coloured, slightly alkaline aqueous fluid called Plasma.


Constituents, having characteristic forms, float in the plasma. They are collectively called the Formed Elements of blood. They include the blood cells and blood platelets. Blood cells are of three types-Erythrocytes, Leukocytes & platelets. Blood circulates within blood vessels in higher

Animals. But other extracellular fluids such as cerebrospinal fluid, interstitial fluid, lymph and aqueous humour occur outside blood vessels.

Plasma contains three major classes of plasma proteins viz, serum albumin, serum globulins and fibrinogen. Plasma proteins serve as a source of proteins for tissue cells. Tissue cells may utilize plasma proteins or forming their cellular proteins. Additionally, albumin and globulins retain water in blood plasma by their osmotic effects. A fall in plasma proteins leads to filtering out of excessive volumes of water from blood to tissues. This is why hands and feet get swollen with accumulated fluid (oedema) in persons suffering from dietary deficiency of proteins. Albumins and globulins also transport many substances such as thyroxin and Fe3+ in combination with them One class of globulins, called-immunoglobulins act as Antibodies. Plasma proteins also maintain the blood pH by neutralizing strong acids and bases. Thus they act as Acid-Base-Buffers.