Tissue provides structural strength, mechanical strength and shows division of labour. A collective number of tissues form organs in the multicellular organism. Simple tissues consist of cells that are structurally and functionally similar. They are made up of only one type of cells.
Three types of simple tissues
Simple tissues are of three types, namely parenchyma, collenchyma and sclerenchyma.
- Parenchyma – They are living cells and walled, soft in nature due to the presence of thin-walled cells
- Collenchyma – These are characterized by uneven thick-walled living cells.
- Sclerenchyma – They have cells with thickened lignified walls, providing them strength and making them waterproof.
The difference between the three simple tissues are tabulated below
|It consists of thin-walled living cells.||It consists of thin-walled living cells.||It consists of dead cells.|
|They are involved in food storage.||They are the chief mechanical tissue in young plants, particularly dicot stems.||It is mainly a mechanical tissue.|
|Comprises a thin cell wall and made up of cellulose.||It comprises an uneven cell wall and is made up of pectin and hemicellulose.||It comprises the hard and thick cell wall and is made up of lignin.|
Functions of parenchyma
- The main function of parenchyma is to store and assimilate food. Hence, they are referred to as food storage tissues.
- It serves as a packing tissue to fill the spaces between other tissues and maintain the plant’s shape and firmness.
- Stores waste products of plants.
Functions of collenchyma
- A mechanical tissue and provides mechanical support and elasticity to the stems of dicot plants.
- Cells possess chloroplast; then, it is involved in manufacturing sugar and starch.
- Provides tensile strength and flexibility to the plant body.
Function of sclerenchyma
- Provides mechanical strength to the plant.
- It makes the plant body rigid, flexible, and elastic.