Animal tissue types

A tissue is a collection of cells that are related to one another and perform comparable functions in an organism. Tissues make up the entire contents of the body, including structures and numerous organs.

The animal body is made up of four fundamental types of tissues, each with its own origin and function. They are as follows: 

Epithelial Tissues:

Epithelial tissues, which are made up of closely packed cells layered together, line the body’s surface. Protection, absorption, and secretion are among their activities. The lining of the mouth and nose, the lining of the digestive system, and the skin all contain epithelial tissues. 

Muscle Tissues:

Smooth muscle tissue is found in the inner linings of organs, skeletal muscle tissue is related to the bone and aids in body movement, and cardiac muscle tissue is located in the heart. These tissues aid in the alteration of a cell’s size. 

Nervous Tissues:

These tissues, which are made up of neurons (brain nerve cells), make up the entire nervous system, including the spinal cord and the brain.

Connective Tissues:

Connective tissues in an animal’s body are made up of many cells that help to maintain the body. They include fat, bone, blood, and cartilage.

Epithelial Tissues

These tissues are responsible for the lining of body surfaces as well as glands. The cells in these tissues are inextricably linked to one another. Because the epithelium lacks blood arteries, it must rely on the other connective tissues for nourishment and other necessities.

The apical surface, which is on the outside and accessible to the body cavity, and the basal surface, which is next to the underlying tissue, are found along the margins of the organs.

The morphology of epithelial cells might be squamous, cuboidal, or columnar. The classification aspects of epithelial tissue are determined by the number of cell layers and the mix of cell shapes. 

Types of Epithelial Tissues and Their Function

Epithelial Tissues are always found on the inner or outer surfaces of organs, and their functions are primarily determined by where they are found. These can be classified into the following categories:

Squamous Epithelium 

These thin, flat cells are densely packed together and prefer the oesophagus, blood arteries, alveoli, and the inner cavities of the mouth. The squamous epithelium tissue protects against mechanical injury and prevents pathogens from entering the body. 

The squamous epithelium can also be organised in many layers, resulting in stratified squamous epithelium tissue. The lining of the oesophagus and the skin are the most common places to find these tissues. 

Cuboidal Epithelium Tissue

These have a cuboidal shape, which is where its name comes from. Secretion, protection, and absorption are the activities of the cuboidal epithelial tissue, which can be found in kidney tubules, salivary glands, and sweat glands.

The stratified cuboidal epithelium tissue is seen on the inner side of the salivary glands and pancreatic ducts when the cuboidal epithelium is structured in many layers.

Columnar Epithelium Tissue 

These are mostly column-like or pillar-like cells that can be found in the gut and stomach lining. Secretion and absorption are two important activities of the columnar epithelial tissue.

Tissue of Ciliated Epithelium

Because columnar epithelial tissues frequently have cilia, they are referred to as ciliated epithelium tissues. These can be found in the tubules of the kidneys, the respiratory tract, and the trachea lining. Their purpose is to aid material flow in a specific direction.

Glandular Epithelium Tissue

The principal function of these heavily modified columnar epithelial tissues is secretion. Sweat glands and tear glands are both home to them.

Muscle Tissues

Muscle tissues are specialised tissues found in animals that use the contraction mechanism to apply force to various regions of the body. Muscle fibres are thin, elongated cells that make up muscle tissues.

The cytoplasm in muscle fibres, known as sarcoplasm, a membrane network known as the sarcoplasmic reticulum, and the surrounding membrane of the muscle fibres, known as the sarcolemma, make up the structure of muscle tissue.

Important properties of muscle tissues are-

Extensibility:

A muscle’s ability to extend itself

Contractibility:

Contractibility refers to a muscle cell’s ability to forcefully shorten itself.

Excitability:

A muscular tissue’s ability to respond to a stimulation delivered by a hormone or a motor neuron.

Elasticity:

Elasticity is a muscle’s capacity to return to its original length after being stretched.

Types of Muscle Tissues and Their Functions 

Muscle tissues, which are primarily responsible for initiating an organism’s movement, also serve a variety of other tasks depending on their type. These are the following:

Skeletal Muscle Tissues 

Skeletal muscle tissues are striated in nature and have neatly formed bundles with tendons attaching them. These have an effect on an organism’s skeletal motions, such as posture and locomotion.

Smooth Muscle Tissues

These have tapering ends and are involuntary and non-striated. They are usually found in the walls of blood vessels such as arteries and veins, as well as in the urinary tract, trachea, and digestive system. Smooth muscular tissues aid in the movement of food up and down the alimentary canal by peristalsis. 

Cardiac Muscle Tissues 

The heart is primarily made up of these. Involuntary and striated, they are branched out at irregular angles to aid in the coordination of heart contractions. 

Nervous Tissues 

The cells that make up the central and peripheral nervous systems are known as nervous tissues. While nervous tissues make up the spinal cord and brain in the central nervous system, they also make up the cranial and spinal nerves, as well as motor and sensory neurons in the peripheral nervous system.

The nerve tissues’ most crucial role is to transmit and convey nerve impulses throughout the body. Axons send forth impulses, which are received by dendrites.

Sensory neurons, motor neurons, and interneurons are the three types of nerve cells.

Connective Tissues 

These are the tissues that support, link, and separate different types of tissues and organs within the body. Cells, collagen fibres, and extracellular matrix make up the extracellular matrix. Inside the body, collective tissues are abundant and can be found in a matrix or in a freely ordered form. 

Types and Functions of Connective Tissues 

Areolar, adipose, bone, cartilage, and fat are examples of connective tissues. Except for blood cells, all cells are involved in collagen secretion.

Tissues of Areolar Connectivity

These can be located beneath the epidermis, in the vicinity of nerves and blood arteries. Their job is to heal tissues and support them.

Tissues of the Adipose System

These can be found in the organs and on the surface of the skin. Their job is to insulate the body with fat presence, and they are made up of fat globules.

Bones

Bones are the body’s skeletal structure, and they’re known for being high in calcium and collagen fibres. They safeguard the body and are where blood cells are produced.

Cartilage

These are made up of chondrocytes, which are made up of flexible intercellular materials and can be found in the ear tips, vertebral column, and bronchi.

Blood

Blood has several functions, including defence, transportation, and, most crucially, homeostasis. Platelets, RBCs, and WBCs, as well as plasma, are all components of blood.

Conclusion

Our bodies are made up of four different types of tissues. The roles of each of these tissues differ. Epithelial tissues, muscular tissues, nerve tissues, and connective tissues are the four types. Knowing about these will aid all students in comprehending basic body facts. It will be especially beneficial to pupils who plan to pursue Biology as a vocation later on, as mastering the principles early on will always come to one’s aid when one is having problems answering a question.

The article provided a thorough understanding of the various types of animal tissues and their functions. Learning about them will be beneficial in the future