• TISSUE

The human body is multi-cellular and complex. The cell functions as the basic functional unit within the body.

Cells performing similar functions join together to form a particular type of tissue. It is also seen that there are more than one cells in a single tissue.

Many such types of tissues are found in the human body. Each has a different function and structure.

• Types of the tissue..

Epithelial Tissue

Connective Tissue

Muscles Tissue

Nervous Tissue

• Epithelial tissue…

This type of tissue is found in many places throughout the body. which are mainly scattered on the surface or on the surface lining.

Epithelial tissue is the tissue lining the inner wall of a body cavity, gland, organ or blood vessel.

Functions of the Epithelial Tissue..

Epithelial tissue is important in forming the inner wall of any organ.

Epithelial tissue acts to provide protection where it is located in the inner wall of an organ.

Epithelium is a tissue associated with making any type of secretion through secretory cells located in the tissue.

Epithelial tissue is the inner wall of the structure and functions in absorption of the material contained therein.

Characteristics of Epithelium Tissue…

Epithelium Tissues are scattered over the basement membrane of any organ or structure.

The cells in this tissue are closely fitted to each other i.e. arranged close together.

The matrix in this tissue is in liquid form.

Due to the presence of special types of cells in this tissue, they are connected with the functions of secretion and absorption.

Classification of Epithelium Tissue.

1. Simple Epithelium Tissue..

This type of tissue is always found in a single layer.

2. Stratified epithelium tissue ..

These tissues are located in multiple layers.

A. Classification of simple epithelium tissue.

This type of tissue is located in the inner wall of any structure or organ. They are associated with activities like absorption and secretion. There are four main types of this type of tissue.

1. Simple squamous epithelium tissue…

These types of tissues are scattered in the basement layer, the inner wall of any structure or organ. Its cells are close to each other and are flat and arranged in a row. Between them is the nucleus.

This type of tissue is found in the lining of the inner wall of the heart, alveoli of the lungs, blood vessels and lymph vessels.

2. Simple cuboidal epithelium tissue….

The shape of the cells in this tissue is cube shaped. which are closely related to each other. This type of tissue is spread over the basement membrane. Usually this tissue is found in renal tubules and thyroid gland.

3. Simple columnar epithelium tissue…

This cell is rectangular in shape. Which are more in length and less in width.

These types of tissues are found in the lining of the respiratory tract and the lining of the alimentary tract. It also contains goblet epithelium cells which perform the function of mucus secretion.

4. Ciliated Simple Epithelium Tissue ….

This tissue contains cells similar to those of cuboidal and columnar tissue. In addition, this tissue has hair-like processes on the margin of the cell, i.e. cilia, so it is called ciliated epithelium tissue.

This type of tissue is especially found in the lining of the respiratory tract and the lining of the fallopian tubes. They are here associated with specific movements.

B. Stratified epithelium tissue…

This type of tissue is composed of more than one layer. In this cell, the size of each cell is not the same. In which cells of each layer are found in irregular size and shape.

In this tissue, the cells of the bottom layer are found to be larger in size and decrease in size as they come to the surface.

This type of tissue is mainly concerned with protection and support of the structure. Stratified epithelium tissue is divided into two parts.

1. Stratified squamous epithelium tissue.

2. Transitional epithelium tissue.

1. Stratified squamous epithelium tissue.

Stratified squamous epithelium tissue is found in multiple layers. It is mainly divided into two parts.

A. Non Keratinized Stratified Epithelium Tissue..

This tissue is mainly found in moist surface areas of the body. Like conjunctiva, esophagus, vaginal cavity, Pharynx etc.

It is a cell with a nucleus. It has a flat shape.

B. Keratinized stratified epithelium tissue…

This type of tissue is mainly found in dry areas of the body such as skin, hair, nails etc.

This tissue mainly contains keratin substance. Which makes water resistant. So mainly evaporation cannot take place. It is the main characteristic of this tissue

2. Transitional epithelium tissue..

This tissue is found in more than one layer but its main characteristic is that it does not have a basement membrane.

Pear shaped cells are seen in this. This type of tissue is mainly found in the inner wall of the urinary bladder.

• Connective tissue..

This type of tissue is scattered in our body in large quantities.

This tissue mainly surrounds all the organs.

Connective tissue consists of different types of cells and their arrangement is not close to each other.

This tissue consists of a network of fibers. which are connected to each other.The matrix is ​​located in the middle of the cell. This matrix is ​​semi-solid jelly-like.

Cells located in the collective tissue.

1. Fibroblasts…

This cell in the connective tissue is flattened and large. It is rod shaped. These cells make elastic fibers and collagen fibers that are scattered throughout the fibrous tissue.

2. Adipocytes ie fat cells

In connective tissue, these cells are found in groups or even single. These cells are very abundant. It varies in size depending on the tissue.

3. Macrophages…

These cells of connective tissue have phagocytic properties. Which is a part of white blood cells.It acts by engulfing and digesting the micro-organisms and foreign material in the tissue and removing them from the tissue. Acts as a protection against infection. These types of cells are arranged in different organs with different names. E.g. In the liver, these cells are arranged as Kupfer cells. In the brain these cells are arranged as microglial cells. Mainly they are connected with protection.

4. Leukocytes.

This is a small cell with an irregular shape. which contains antibodies and functions related to maintaining immunity.

5. Mast cells.

This cell has the same structure as the cells of basophils found in the blood. It produces histamine and heparin.

Histamine responds to allergic reactions and heparin acts as an anticoagulant.

Functions of the Connective Tissue..

Connective tissues are widely distributed in the body. This is strong tissue. It performs the following functions.

1. This tissue helps to connect one structure to another by being a network of fibers.
2. Fibers in connective tissue that provide structural support around any organ.
3. Connective tissue is strong and supports the structure and holds the structure together.
4. Connective tissue being strong also acts as a protection of the organs below it.
5. Cells in connective tissue also perform the function of transporting material from one tissue to another.
6. Retains body heat and acts as insulation.

Classification of connective tissue

Areolar connective tissue

This type of tissue is located in many places in the body. It has an arrangement of cells far from each other. Its matrix is ​​semi-solid and soft jelly-like. Mainly all the cells of connective tissue i.e. fibroblasts, macrophages and mast cells are also present in it. Interspersed between the tissues are elastic and collagen fibers that are important for connecting and providing support to the structure.

This type of tissue is found in the walls of blood vessels and under the skin and in many other places.

Adipose tissue.

This type of tissue contains fat cells and fat globules. Its matrix is ​​solid. This type of tissue acts as a protective layer around some delicate organs inside the body. E.g. kidney.

There are two types of this tissue.

1. White adipose tissue.

It accounts for 20 to 25% of the total body weight. The growth of R tissue is seen on the energy intake of a person and physical activity in his body. This tissue is loose connective tissue.

These tissues are located around the kidney, eye etc. structures. It acts to provide support and protection to the structure.

2. Brown adipose tissue.

This type of tissue is found only within the newborn. Within which a large network of blood capillaries is connected. Due to which it is metabolized and produces energy and heat and is very important for maintaining the temperature of the baby’s body. As the temperature regulating center is not mature in the child, this tissue acts as an extra body heat maintainer. This tissue is loose connective tissue.

Dense connective tissue..

Fibrous tissue.

Bundles of these fibers are arranged between the tissues and contain little matrix. Fibrocytes cells are also arranged among the tissues.

This is a type of dense connective tissue whose specific functions are as follows.

It gives attachment of muscles to bone.

Provides attachment to bones with ligaments.

The periosteum layer of the outer wall of the bone is made up of this type of tissue.

They are also there for the protection of delicate structures in the cavity of the body.

Elastic tissue.

This tissue consists of branches of elastic fibers.

Fibroblast cells are also located between the tissues. These tissues are mainly located in organs with elasticity. E.g. This type of tissue is also present in the wall between trachea, bronchi, blood vessels.

Blood.

Blood is a special type of connective tissue about which complete information is given in detail in the unit of blood in cardio vascular system.

Lymphoid tissue.

Branches of reticular fibers are located in this tissue.

Its matrix is ​​semi-solid. It contains cells similar to the WBC cells found in the blood.

This type of tissue is found in spleen, lymph node, appendix, tonsil etc. This type of tissue works for protection of the body.

Cartilage..

Chondrocyte cells are present in cartilage. which are in the matrix. Its matrix is ​​solid. There are three main types of cartilage.

1. Highline cartilage..

This cartilage is shiny and transparent. It contains collagen fibers. This cartilage is located at the two ends of the bone i.e. this cartilage is found at the joint. This cartilage provides pressure bearing capacity to the joint and functions for smooth and painless movement. This cartilage is located at the ends of the long bones, at the front of the ribs, and at the trachea and larynx.

2. Fibro cartilage…

Chondrocyte cells in this cartilage are scattered in a matrix. It also contains collagen fibers. This cartilage acts to provide support and is located in the intervertebral disc. The function of this cartilage is to maintain the movement and flexibility of the body.

3. Elastic cartilage..

Chondrocyte cells are present in this cartilage. It forms a network of elastic fibers in the matrix. The main function of this type of cartilage is to maintain the shape and flexibility of the organ. These cartilages are located in the external ear and larynges.

Bone..

Bone is a type of connective tissue. Osteocyte cells are present in its structure.

It is a type of dense connective tissue. This works for support and protection in the body. Gives attachment to muscles. So different types of movement can happen. There are two main types of bone.

Compaq Bone

spongy bone

The main function of bone in the body is to provide a structural framework to the body.

• Muscle tissue…

Muscles tissues are made up of some contractile cells. they have power to contract it self.

there are total three types of muscles.

1. Skeletal muscles…

These muscles are also known as other voluntary muscles because they act according to our will. With its help the body moves. So it is called voluntary muscles.

These are straight type muscles.

Many muscle fiber bundles are present in the structure of skeletal muscles.

Fiber cells are located between muscle fibers. They are arranged in a cylindrical shape. It also contains the nucleus.

Skeletal muscles act for different types of moments.

2. Smooth muscles…

These muscles are also called voluntary muscles because they are not under our voluntary control. These muscles are of unstripped type i.e. circular shape.

Looking at these muscles under a microscope, cigarette-shaped cells are seen inside. A nucleus is present in them. These types of muscles are located in blood vessels, lining of respiratory tract, lining of alimentary tract.

3. Cardiac muscles…

These muscles are voluntary type muscles. Its function is also not under our control. These muscles are especially located in the middle layer of the heart, the myocardium. It is called cardiac muscle.

These muscles have straight fibers. They are closely related to each other. The pumping action of the heart is seen due to the contraction and relaxation of these muscles.

• Nervous tissue..

These tissues are made up of nerve cells. The nerve cell is called a neuron. Each neuron has a structure of cell body, axon and dendrites.

Nervous tissue is divided into two types on the basis of cells.

1. Excitable Sales.

Which includes cells that carry and receive impulses i.e. include neurons. This neuron has properties of irritability and conductivity.

2. Non excitable cell.

This cell is also called glial cell. which are not involved in the conduction of impulses and function to provide support to nerves and nerve cells.

Functions of Muscle Tissue..

Contraction and relaxation help the body to perform different types of movement.

Helps to maintain body poster.

The body performs the function of heat production.

It maintains normal posture by maintaining proper muscle tone through the functioning of the nervous system.

Muscle fatigue occurs due to prolonged muscle contraction.

• Tissue regeneration..

This is a process in which dead or damaged cells and tissues are repaired and new tissues and cells are formed which is called tissue regeneration. Mainly seen in the following types.

1. Liable Sale..

These cell bodies are the type of cells that continuously undergo cell division. For example cells from bone marrow, cells from blood, spleen and lymphoid tissue.

2. Stable cell..

These cells have the capacity to multiply and divide but do not divide continuously. After some time, cell division in them stops. For example smooth muscle, the cells inside the bone.

3. Permanent sale.

Once these cells have completed normal growth and maculation, they never have the capacity to divide again. These cells include cardiac cells, nerve cells.