Tissues are a group of cells that combine together to form an organ. The tissue of the same organ consists of similar cells having the same structures to perform a specific function. They are not present in the unicellular organisms. They are present only in multi-cellular organisms.
On the basis of parts of the animal body or plant body, tissues can be broadly divided as:
- epithelial tissue
- muscle tissue
- connective tissue
- nervous tissue
Let us look in details about Tissues in Plants
Plant tissues are different from the animal tissues because plants perform completely different functions compared to that of animals. Plants cannot sleep, talk, run etc. but they can use water, carbon dioxide and sunlight from the atmosphere to make food (glucose) for themselves and release oxygen as a byproduct. Oxygen released as a byproduct is utilized by humans during the process of Respiration. Because of the difference in the functions of plants and animals, there is a difference in animal and plant cell. These cells are aggregated together to form plant or animal tissue. Let us look more into one of the plant tissue i.e. parenchyma tissue.
They are made up of parenchyma cells. These cells are abundantly found in all major parts of higher plants. At the cellular level, they are circular in shape. But when they are tightly packed to form tissues then they take a square shape. The vacuoles present in it are large and contain secretions like starch, oil and some crystals. Some hybrid varieties of parenchyma cells are also present depending on the part of the body. They are of three types:
1. Add chloroplast: In this type of cell, chloroplast is added in the cell and the cell can carry out the Process of Photosynthesis. Due to the presence of chloroplast, the cell is green in color.
2. No chloroplast: In this type of cell no chloroplast is present inside the cell and no photosynthesis process can be carried out in such cells. It is used for storing water and food.
3. No push: In this type of cell some air space is left in between. Hence they are not tightly packed.
This is just a brief layout of the types of tissue and plant tissue. Continue learning about Animal Tissue and muscular tissue in the human body with video lecture @byjus.com