Epithelium vs Connective Tissue
Tissue is a group of physically linked cells with associated intercellular substances, and are specialized in particular function or functions. This specialization whilst leading to increased efficiency of action by the organism, as a whole, makes the coordination for a single function like digestion somewhat complicated. Connective tissue and epithelial tissue are two such types. They work in close connection with each other often lying together around and within organs and systems.
Connective tissue is the main supporting tissue of the body. It includes the skeletal tissue, loose connective tissue, fibrous connective tissue, and dentine and haemopoietic tissue. They bind other tissues together, and around the organs of the body, they form sheaths, separating them, so that they do not interfere with the work of others. Connective tissue is a composite tissue made up of different kinds of cells of the embryonic mesodermal origin. It mainly consists of fiber, which is non-living products of cells, and a fluid semi fluid intercellular matrix consisting of hyaluronic acid, chondroitin, chondroitin sulphate and keratin sulphate. The cells are usually wide spread, and perform the function of protection through macrophages and mast cells. An extensive vascular network is often present and is primarily concerned with the supply of other tissues with nutrients and oxygen rather than the connective tissue itself. It also provides insulation of body heat by the function of the adipose tissue, provide a supporting network by bones and muscles of skeletal tissue and produce blood and lymph by haemopoietic tissue.
Epithelial tissue is arranged in single or multilayer sheets, and it covers the internal and external surfaces of an organism. True epithelial tissue arises from the embryonic ectoderm, which provides epithelium for the skin, nervous system and parts of the mid gut and the hind gut. Furthermore, the embryonic endoderm provides epithelium for the remainder of the alimentary canal, liver, and pancreas. The epithelial cells are cemented together by hyaluronic acid. The bottom layer of the epithelium rests on the basement membrane composed of collagenous fibers and is avascular. The epithelium depends on the under laying connective tissue for nutrition, communication and oxygen. There are two types of epithelial tissues; simple epithilum, composed of single layer of cells found lining the internal surfaces, and the compound epithilum, composed of multiple cell layer found lining external surfaces and distendible internal surfaces.
What is the difference between Epithelium and Connective Tissue?
• Both connective and epithelial tissues mainly have a structural function. They both consist of a strong fibrous component. But apart from that differ immensely.
• The connective tissue forms the sub types of skeletal tissue, forming strong bones and muscle, as well as fluid tissue such as blood and lymph. But the epithelium rarely shows a variation in tissue structure apart from the number of layers of cells.
• The connective tissue is supplied with a rich network of nerves and blood capillaries where as the epithelium has no such arrangement.
• The epithelial cells are always arranged in an orderly fashion on the basement membrane, but the connective tissue despite, sometimes, having an orderly cellular arrangement does not include a basement membrane.
• These two tissue types have the common function of protection from foreign bodies and toxins, as well as mechanical damage. Yet, the connective tissues alone perform the additional functions of insulation, provide a supporting network by bones and muscles, and all functions performed by blood and lymph.
• These two types of tissues together form the majority of organs and systems that complete an animal body.