Tissues are made of similar cells that are specialized in carrying out specific function.
Types of tissues
The two types of tissues are
Plant tissue
Animal tissue
Plant tissue
The different types of plant tissues are as follows:
Meristematic tissue
Permanent tissue
Meristematic tissue
Meristematic tissues are responsible for the growth of the plant. The cytoplasm in meristematic tissue is dense. They have thin cellulose walls and prominent nuclei. The Three Types of meristematic tissues are as follows:
Apical Meristem
Intercalary Meristem
Lateral Meristem
Apical meristem
Apical Meristem is present at the tip of the stem and roots that helps them to grow.
Intercalary meristem
Intercalary meristem is present in the nodes of plants that help to grow its length.
Lateral meristem
Lateral Meristem is present at the bottom of the stem and root which helps to increase its girth.
Cork tissue
The Secondary Meristem, which is located in the cortex forms a layer of cells, which is called the cork. The cells of the cork are dead and tightly packed that have no intercellular spaces between them. However, it allows gases and water to pass through it. It also acts as a protective shield that protects the plant from wear and tear. It forms multiple layers of cork that protect the internal parts of the plant body.
Permanent tissue
When meristematic tissue divides to an extent that it cannot be divided further and takes up the specific role is called permanent tissues. The two types of permanent tissues are as follows:
Simple permanent tissue
Complex permanent tissue
Simple permanent tissue
Parenchyma is considered as the simple permanent tissue, which is generally found below the epidermis. The cells of parenchyma are loosely packed, unspecialized, and have thin cell walls. Parenchyma generally stores food. The following are the different types of parenchyma:
Chlorenchyma: Some parenchyma that contains chlorophyll and carries our photosynthesis and hence are called chlorenchyma.
Collenchyma: It provides flexibility to some parts such as stem of the plants that protects them from breaking down. It is known as Collenchyma. It can be found in leaf stocks below epidermis its cells are living elongated, and thick at the corners they have less intercellular space.
Aerenchyma: the parenchyma in aquatic plants acts as an airbag hence it is called aerenchyma.
Sclerenchyma: This tissue provides toughness and hardness to the plant. Its cells are dead. They have long and narrow walls, which are thick because of Lignin. They have very little intercellular space.
Epidermis
The epidermis is the outermost layer of the cell. It is made of single layer of cells. Epidermis provides protection to all parts of the plant.
The epidermal cells of plants grown in dry region are thick that prevent loss of water.
The epidermal cells on the aerial parts of plant secrete wax that protects it against water loss, mechanical injury, and parasitic attacks.
The epidermal cells found in roots help to absorb water and they have long hair that increases the total surface area of absorption.
Complex permanent tissue
Complex tissues are made of multiple types of cells. The two complex tissues found in plants are:
Xylem
Pholem
Xylem
Xylem is a conductive tissue that helps in the transportation of water and mineral from the roots to the leaves of a plant. The different parts of xylem are as follows:
Tracheids and vessels: Tracheids and vessels are made of dead cells which have thick walls. These tubular structures transport water and mineral vertically from roots to other parts of the plant.
Xylem parenchyma: It stores the food.
Xylem fibres: It provides support to the xylem.
Pholem
Phloem is a tubular structure that transports food prepared by leaves to other parts of the plant. Pholem is made of different types of cells, which are sieve cells, sieve tube, companion cells, phloem fiber and phloem parenchyma.
Sieve cells, sieve tubes, and companion cell helps to transport food material to other parts of plant.
Pholem parenchyma stores the food and other material such as resin and latex.
Animal tissues
The different types of tissues found in animals are as follows:
Epithelial tissue
Connective tissue
Muscular tissue
Nervous tissue
Epithelial tissue
Epithelial tissues are the protective tissues that cover almost every organ in animals. It has very little intercellular space between its cells.
The different types of epithelial tissue are as follows:
Squamous tissue: This tissue is thin and flat that covers the esophagus and lining of the mouth. This is also called the simple squamous epithelium tissue.
Stratified squamous: This tissue is arranged in layers, which is usually found under the skin that protects it from wear and tear.
Columnar (Ciliated): This tissue is generally found where absorption and secretion happens (example: around small intestine and glands), these tissues have hair like structure that help mucus push forward.
Cuboidal epithelium tissue:Cuboidal epithelium tissue is generally found in the lining of kidney tubules and duct of the salivary gland that provides mechanical support. Some of these tissues folds inward to form multicellular gland that is why they are also called the glandular epithelium.
Connective tissue
Connective tissue helps to connect different parts in the body. Some of the important connective tissues are as follows:
Blood: Blood has fluid called plasma that contains red blood corpuscles, white blood corpuscles, platelets, protein, salts, and hormones. Blood transports gases, digested food, hormones, and waste material to different parts of the body.
Bones: Bone is another connective tissue that is composed of calcium and phosphorus compounds. It provides structure and support to our body. It is strong and non-flexible tissue.
Ligament: Ligament connects two bones with each other. It is a flexible tissue.
Tendons: The muscles are connected to the bones with the help of tendons. Tendon is a fibrous strong tissue but has limited flexibility.
Cartilage: Cartilage is made of proteins and sugars. It smoothens the bones at joints. Cartilage is generally found in the nose, ear, and trachea.
Areolar tissue: Areolar connective tissue fills the space inside the organs it supports internal organ and helps in the repair of tissues. Areolar tissue is generally found between skin and muscles. It is also found around the blood vessels, nerves, and in the bone marrow.
Muscular tissue
Muscular tissue helps in the movement of our body. It is formed of elongated cells. It contains special proteins (contractile proteins), which helps in the contraction and relaxation of muscles.
Following are the different types of muscles tissues:
Striated muscle: These muscles are attached to our bones that helps in the body movement. These muscles shows light and dark bands when observed under the microscope, hence they are called striated muscles. The cells of this tissue are long, cylindrical, unbranched, and multinucleate.
Unstriated muscle: These muscles are also called involuntary muscle because we cannot control its movement. It is generally found in the alimentary canal and blood vessels. The cells of these muscles are pointed and uninucleated.
Cardiac muscle: Cardiac muscle is found in the heart which helps in contraction and relaxation. The cell of these tissues are cylindrical, branched and uninucleate.
Nervous tissue
Nervous tissues help in transmitting stimuli very fast from one place to another in the body. The brain, spinal cord, and nerves together are composed of the nervous tissue. The cells of nervous tissues are called neurons.
A single neuron has nucleus, dendrites, Axon and nerve ending.
