Animal tissues are understood to be that concentration of similar cells that have a particular function and structure, vital for the organism of the living being. These tissues obtain an initial shape when the so-called blastula derived from the fertilized ovum differentiates into three germ layers, which are mesoderm, endoderm and ectoderm and through which the cells differentiate, certain groups of cells originate more specialized units that form organs that They are composed, in a general sense, of numerous tissues made up of many cells that have the same function. It should be noted that the science in charge of studying the arrangement and structure of tissues is known as histology.
According to different biologists, animal tissues can be classified into: epithelial, connective, muscular and nervous that perform a specialized function.
Epithelial tissue: made up of the continuous cells that line the body surface or covering the internal cavities, these cells are closely united with little intercellular substance between them; the primary function of these tissues is to preserve infection and injury. Epithelia are classified into lining epithelium, glandular epithelium, and sensory epithelium.
Muscle tissue: the cells of this tissue are those that enable the movement of internal organs, these cells or muscle fibers have a tapered shape, characterized by being highly modified thanks to the presence of elastic and contractile myofibrils in their cytoplasm. Muscle tissues can be of three cardiac types, striated and smooth.
Connective tissue: these are in charge of connecting one tissue to another, since together they maintain and support the different parts of the body, so their main function is to provide support and protection, connective tissues are classified as: adipose, bone, blood, cartilaginous, hematopoietic and conjunctive.
Nervous tissue: composed of a conglomerate of cells that are in charge of transferring information from one area of the body to another, in order to coordinate the functioning of a given organism and regulate its behavior, that is, it receives stimuli and transports them through the rest of the body. Body. They can be classified into two types that are: neurons and neuroglia.
