Blood is a fluid connective tissue. In blood, the cells move in a fluid matrix called blood plasma. The cells in blood are different from the other connective tissue cells, both in structure and functions. Blood plasma is a straw coloured, slightly alkaline fluid. Blood plasma contains cells called blood corpuscles and blood platelets. Blood cells are of two types-Erythrocytes and Leucocytes. Blood circulates within the blood vessels throughout the body and thus, connect every part of the body.