In biology, a tissue is a collection of cells that have a common arrangement and serve the same role. The term tissue derives from the French word tissu, which implies “to weave.”

Animal Tissues

Animal tissues are made up of animal cells that have been clustered together. The composition, role, and origin of these tissues are all distinct. Epithelial, connective, elastic, and nervous tissues are the four types of tissues found in animals.

Plant Tissues 

A tissue is a set of cells of similar configurations that collaborate to perform a particular purpose. Permanent and meristematic tissues are two types of plant tissues.

Permanent and meristematic tissues are two types of plant tissues. 

• Meristematic tissues:
  These tissues can divide quickly and mature quickly. They contribute to the vegetation’s big development. These cells are responsible for the plant’s growth in duration and diameter. Meristematic cells are living cubical cells with a large nucleus.

• Permanent tissues:
  These cells have lost their capacity to distribute, but they are specialised to provide the plant with elasticity, resilience, and strength. These tissues may also be divided into the following groups:
  (i) Simple permanent tissues
  (ii) Complex permanent tissues

• There are polygonal cells that are alive and have a wide central vacuole and intercellular gaps within them. Ground tissue and pith are formed by parenchymatous cells. 
• Chlorenchyma is a form of parenchyma that produces chloroplasts. Photosynthesis is supported by the chlorenchyma. 
• Aerenchyma is a form of parenchyma that comprises broad air voids. Aerenchyma’s primary role is to provide buoyancy. 
• In vegetables and fruits, certain parenchymatous cells serve as starch storage chambers.

There are live cells that have been spread out and have minute intercellular differences. Pectin and cellulose make up their cell walls. Collenchyma is located in the margins of leaves and branches, and it provides plants with structural flexibility and mechanical support.

There are elongated, dying cells with layers of lignin in their cell walls. There are no holes between the cells. Sclerenchyma can be present on the outside of seeds and nuts, as well as along vascular tissues in stems and leaf veins. Sclerenchyma gives the plant its power.

It aids in the transfer of water and dissolved compounds in the farm. Vessels, tracheids, xylem fibres, and xylem parenchyma are some of the xylem’s several elements. Lignin is found in Xylem fibres and Tracheids, and it gives structural support to the plant.

This tissue assists in the flow of food across the plant. Phloem fibres, sieve channels, phloem parenchyma, and partner cells are some of the several components of phloem.

• Epithelial tissue
  The defensive wrapping and inner lining of the body and organs are formed by epithelial tissues. These tissues were the first to develop during embryonic growth and were the first to evolve during evolution. They emerge from the embryo’s ectoderm, mesoderm, and endoderm.Epithelial Tissue CharacteristicsThe following are some of the most essential features of epithelial tissues:
• These may be multi-layered or single-layered. 
• Tissues have the potential to rebuild themselves. 
• Gap junctions, close junctions, zonula adherens, desmosomes, and interdigitation bring these cells together. 
• These cells’ plasma membranes are divided into flagella, cilia, and microvilli.
• Muscular Tissue
  The embryo’s mesoderm transforms into muscle tissue. It is divided into three categories:
• Cardiac
• Smooth
• Skeletal

Muscle tissue has the following purposes:

• It assists in locomotion and movement. 
• It helps to hold the bones and other structures in place. 
• Peristalsis and parturition are regulated by it.

In this chapter, we learned about the tissues, their types and the characteristics. We also learned about the types of plant and animal tissues.

1. What is the concept of tissue in the human body?
   The tissue is a set of cells with identical structures that work together as a team. The intercellular matrix, a non-living substance, occupies the gaps between the cells. This may be plentiful in certain tissues while becoming sparse in others. 
2. What is the significance of tissues?
   a) It defends the organs from damage or shock.
   b) It often binds to a variety of body pieces, such as ligaments, which attach bones to one another.
   c) It also acts as a source of energy for our bodies, as blood carries nutrients to different areas of the body. 
   
3. What is nervous tissue? And what does it do?
   The cortex, spinal cord, and nerves all contain nerve tissue. It is in charge of organising and regulating several bodily functions.
4. Blood is a form of which tissue?
   Connective tissue.
5. What’s the differentiation between a tissue system and an organ system?
   Tissues are collections of identical cells that have the same purpose. An organ is a device made up of at least two distinct forms of tissue that play a particular role in the body.