Epithelial tissue: It is involved in secretion, protection and absorption and
covers the body of most vertebrates. Additionally, it covers the inner surface
of those organisms that possess a body cavity. Epithelial tissue also
encapsulates the blood and lymph vessels and is classified according to its
Connective tissue: It is generated from the mesoderm layer of the embryo.
It is involved in the connection of all tissues and also supports the body.
Connective tissue is composed of five main types;
Loose connective tissue (adipose, collagen fibers)
Fibrous connective tissue (tendons, ligaments)
Muscular tissue: The body as a whole, as well as individual internal organs,
move by means of muscular tissue. It is classified as skeletal, smooth or
cardiac according to its structure. The skeletal muscles work in conjunction
with bones to provide movement of the body. The smooth muscles
contribute mostly to the structure of internal organs and to the movement
of blood in the vessels. The cardiac muscles are responsible for the function
of the heart.
Nervous tissue: It consists of neurons and glial cells and is involved in the
transmission of impulses in the body.