Types of Animal Tissue The different types of animal tissues include:
Epithelial Tissue
Epithelial tissues form the protective covering and inner lining of the body and organs. These tissues were the first to evolve during evolution and were first formed during embryonic development. They develop from the ectoderm, mesoderm and endoderm of the embryo.
Characteristics of Epithelial Tissues
Following are the important characteristics of epithelial tissues:
These can be single-layered or multi-layered.
The tissues have the power to regenerate.
These are held together by gap junctions, tight junctions, zonula adheren, desmosomes, or interdigitation.
The plasma membrane of these cells is specialized into flagella, cilia, and microvilli.
Connective Tissue
Connective tissues develop from the mesodermal cells of the embryo. they support and bind other tissues in the body. These are made up of three components:
Intercellular Matrix: It is made up of mucopolysaccharide, specifically hyaluronic acid.
Cells: The major cells include fibroblasts, adipocytes, plasma cells and mast cells.
Fibres: Connective tissues are made up of three types of fibres, namely, collagen fibre, elastic fibre, reticular fibre.
The connective tissues perform the following functions:
They attach organs and tissues together.
They store fat in the form of adipose tissues.
They help in repairing tissues.
They prevent the organs from mechanical shocks.
The organs also help in defence
Muscular Tissue
The muscular tissue develops from the mesoderm of the embryo. It is classified into three types:
Cardiac
Smooth
Skeletal
Muscular tissue performs the following functions:
It helps in movement and locomotion.
It supports the bones and other structures.
It is responsible for peristalsis and parturition.
Nervous Tissue
Nervous tissue makes up the peripheral and the CNS. It develops from the ectoderm of the embryo. It possesses the ability to initiate and transmit the nerve impulse. Its main components include:
Neurons – These are the structural and functional unit of nervous system. It comprises an axon, cell body and dendrites.
Neuroglia – These are special cells found in the brain and spinal cord. They provide support to the neurons and fibres.
Neurosecretory Cells – These function as endocrine organs. They release chemical from the axons direcly into blood.
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