The word tissue is derived from the English word “tissu”. This is a past participle of the verb tisser which means “to weave”. The branch of science which deals with the study of tissues is known as “histology” or in case it is studied with the interconnection of disease is known as histopathology.
Definition of Tissue
Tissue can be defined as” The biological organisational level between the cells to form a complete organ is termed as tissue.” These are generally a group of similar cells with their extracellular material.
Types of Tissues
Tissues are broadly classified into two types :
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Plant tissue
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Animal tissue
Let us discuss both the tissues in detail.
Plant Tissue:
The plant tissues are further broadly classified into three types. Those are:
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Epidermis tissue
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Vascular tissue
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Ground tissue
Epidermis Tissue: These tissues are the cells that build up the outer surface of the leaves and the young plant body.
Vascular Tissue: This tissue is further made up of two primary components namely the xylem and phloem. These components are used to transport fluids and nutrients internally in a plant
Xylem:
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The xylem consists of four kinds of cells which include the tracheids, vessels, xylem fibres or xylem parenchyma.
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These are the main parts to transport minerals into the vascular system.
Phloem:
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The phloem mainly consists of a sieve tube, companion cell, phloem fibre, phloem parenchyma.
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This part is very essential to the plant as it comprises the plumbing system to the plant.
Ground Tissue:
Animal Tissue:
These tissues are further broadly classified into four categories. Those are :
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Connective tissue
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Nervous tissue
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Epithelial tissue
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Muscle tissue
Let us discuss the tissues in detail.
Connective Tissue: These types of tissues are generally fibrous tissues made up of non-living material, known as extracellular cell matrix. These matrices can be liquid or rigid.
Nervous Tissue: The central nervous system and the peripheral nervous system combine to comprise the nervous tissue. In the central nervous system, the neural tissues present make the brain and spinal cord. On the other hand, the peripheral nervous system comprises the cranial nerves and spinal nerves.
Epithelial Tissue: These tissues comprise the cover tissues of a body. These tissues include the skin, the airways, surfaces of soft organs, the reproductive tract, and the inner lining of the digestive tract.
Muscle Tissue: These tissues make the visceral or smooth muscles that are found in the inner lining of the organs. These tissues are also found in the heart.