The kind of connective tissue that contains a liquid matrix is the blood. The blood is primarily composed of erythrocytes, or red blood cells, leukocytes, or white blood cells, and platelets.
Multicellular organisms are made up of specialized groups of cells, known as tissues. Aside from connective tissues, the three other types of tissues found in animals are epithelial, muscular and nervous.
Connective tissues are comprised of thinly dispersed cells in an extracellular material called the matrix. Fillers, such as ground substance and fibers, are the primary constitution of matrices, which can be solid, liquid or jelly-like. The blood is a special type of loose connective tissue that characteristically lacks fibers and is embedded in a fluid ground substance called plasma.