by: Katie Harper
What is a Tissue?
Any of the distinct types of material of which animals or plants are made, consisting of specialized cells and their products. It is apart of an organism consisting of a large number of cells having asimilar structure and function
The four types of Tissue are;
1. Epithelial Tissue
2. Connective Tissue
3. Muscle Tissue
4. Nervous Tissue
~ Epithelial cells cover the inner and outer linings of body cavities, such as the stomach and the urinary tract. As the barrier between the outside world’s contaminants and the body, these cells replicate often to replace damaged or dead cells. Many layers provide better protection, meaning if one layer is lost, the underlying tissue is still protected.
~ Stores nutritive material as neutral fat. Brown fat, a metabolically more active tissue, is only found in the human fetus. Forms soft elastic pads between organs and other structure. Serves as an insulation against the cold. This is especially true in aquatic mammals where it also has a buoyancy function. It improves the form of the body.
~ Movement, Maintenance of posture, Joint stabilization, Heat generation.
~ Nervous tissue allows an organism to sense stimuli in both the internal and external environment.The stimuli are analysed and integrated to provide appropriate, co-ordinate responses in various organs. The afferent or sensory neurons conduct nerve impulses from the sense organs and receptors to the central nervous system. Intern-uncial or connector neurons supply the connection between the afferent and efferent neurons as well as different parts of the central nervous system. Efferent or somatic motor neurons transmit the impulse from the central nervous system to a muscle (the effected organ) which then react to the initial stimulus. Autonomic motor or efferent neurons transmit impulses to the involuntary muscles and glands.
Epithelium tissue can be classified in two categories; simple epithelium and stratified epithelium.
The connective tissue is divided into 8 different types; Bone, Cartilage, Dense Connective Tissue, Loose Connection Tissue, Areolar Tissue, Adipose Tissue, Reticular Connective Tissue, and Blood.