Question

explain : (1) collenchyma (2) sclerenchyma (3) aerenchyma​

Answer 1

Answer:

1. Parenchyma is a simple permanent plant tissue composed of thin-walled, unspecialized cells separated by intercellular spaces and which have not lost their power of division.
2. Parenchyma provides support to plants and also stores food. It is a basic packing tissue in plants. Parenchyma of stems and roots store water and nutrients. Sometimes it contains chlorophyll and performs photosynthesis ( called chlorenchyma) . In aquatic plants, parenchyma ( called aerenchyma) shows large air spaces to give buoyancy to plant.

1. Collenchyma is a simple permanent plant tissue containing cells characterized by cell walls unevenly thickened with cellulose and hemicellulose and functioning mainly as flexible and supportive tissue.
2. Collenchyma allows easy bending in various parts of the plant without breaking. It also provides mechanical support to the plants.

1. Sclerenchyma is also a simple permanent plant tissue containing dead cells with heavily lignified cell walls and functioning as a strengthening tissue.
2. Sclerenchyma provides strength and protection to the plants.

Answer 2

Answer:

1.)COLLENCHYMA:- a plant tissue that consists of living usually elongated cells with unevenly thickened walls and acts as support especially in areas of primary growth.

2.) Definition of sclerenchyma:-

a protective or supporting tissue in higher plants composed of cells with walls thickened and often lignified.

3.) Aerenchyma:- It is a spongy tissue that forms spaces or air channels in the leaves, stems and roots of some plants, which allows exchange of gases between the shoot and the root.The channels of air-filled cavities (see image to right) provide a low-resistance internal pathway for the exchange of gases such as oxygen and ethylene between the plant above the water and the submerged tissues. Aerenchyma is also widespread in aquatic and wetland plants which must grow in hypoxic soils.