Plant Tissues - Part II (Meristematic + Permanent Tissues) - Class 9 Biology скачать в хорошем качестве

Plant Tissues - Part II (Meristematic + Permanent Tissues) - Class 9 Biology

This is an animated video of the various types of tissues present in a plant. Do Like and Subscribe to keep receiving such informational videos. Follow @ Facebook : www.facebook.com/biotechregime.regime.1 Follow @ Instagram : www.instagram.com/biotechregime Question-bank webpage : [email protected] Video credit - amritacreate Video editing - BiotechRegime What is a tissue? it is a group of similar specialized cells that would perform the same function. In a plant body, on the basis of the function, plant tissues are of 2 types-meristematic tissue and permanent tissue . Meristematic tissues are the dividing tissues which perform cell division throughout the life of the plant and add new cells to the plant body resulting in its growth. Meristematic cells are small, spherical or ovoid, with thin cell wall and no vacuoles. these meristematic tissues are present in patches and on the basis of their location they are of 3 types apical, lateral and intercalary. The apical meristematic tissue is present at the root and the shoot tips and are responsible for growth in the length or height of the plant. We see that as the plant grows, its diameter also increases. The lateral meristem present at the sides of the plant are responsible for the increase in this diameter of girth of the plant. The third type of meristematic tissue ie the intercalary meristem is responsible for formation of new leaves and branches in all types of plants. These intercalary meristems are present in small patches at the base of the nodes, at the base of the leaves and in the internode region All these meristematic tissues together form the different organs of the plant and result in the growth of all these organ throughout the life of the plant. The new cell formed by these meristematic tissues then differentiate into specific type of permanent tissues with particular structure and function. And these permanent tissues provide mass and volume to the whole plant body and perform all the basic plant functions. such as absorption of water and minerals transportation transpiration photosynthesis etc. On the basis of composition the permanent tissues are divided into simple permanent tissue and complex permanent tissue . A simple permanent tissue is made up of all similar cells which have same structure and function. on the basis of their function they are again divided into 3 types parenchyma collenchyma and schlerenchyma. A parenchymatous tissue is made up of all living spherical cells with thin cellulosic cell wall and intercellular spaces. These perform storage function, or photosynthesis or even make the aquatic plants float on water. Parenchymatous tissues are present in all the soft parts of the plant. The Collenchymatous tissues are made of all living cells with thin cell wall thickened at the corners and no intercellular spaces. These are thus harder and provide elasticity, mechanical support and tensile strength to the plant body. These are present in hard living parts of the plant such as leave petiole, stem and roots. The sclerenchymatous tissues are made of dead cells with thick lignified cell wall to provide protection and are present in the hardest parts like the bark, husk of coconut and hard covering of fruits, nuts and seeds. The complex permanent tissue are made up of a group of different cells which together perform one function and hence are named complex. Two types of complex tissues are present in a plant – phloem and xylem. Xylem is a complex group of 4 cells – the tracheids, vessels and xylem parenchyma and xylem fiber. The tracheids and vessels are tube like structures which conduct water from the roots to the other parts of the plant. Likewise, phloem consists of sieve tubes, companion cells, phloem fiber and phloem parenchyma, and all these together transport food from leaves to the rest parts of the plant.