Рет қаралды 148,794
In this Science (Biology) video in Hindi for class 9th we explained the functions and properties of meristematic tissue which is a type of plant tissues. This is a topic of Chapter 6 of science from NCERT.
A group of cells that are similar in structure and/or work together to achieve a particular function forms a tissue.
In plants tissues are broadly categorised as :-
1. 𝑀𝑒𝑟𝑖𝑠𝑡𝑒𝑚𝑎𝑡𝑖𝑐 𝑇𝑖𝑠𝑠𝑢𝑒
2. 𝑃𝑒𝑟𝑚𝑎𝑛𝑒𝑛𝑡 𝑇𝑖𝑠𝑠𝑢𝑒
(𝑎) 𝑆𝑖𝑚𝑝𝑙𝑒 𝑃𝑒𝑟𝑚𝑎𝑛𝑒𝑛𝑡 𝑇𝑖𝑠𝑠𝑢𝑒
(𝑏) 𝐶𝑜𝑚𝑝𝑙𝑒𝑥 𝑃𝑒𝑟𝑚𝑎𝑛𝑒𝑛𝑡 𝑇𝑖𝑠𝑠𝑢𝑒
Meristematic tussues are comprised of meristematic cells which are undifferentiated cells and which can divide. Whereas, permanent tissues are comprised of differentiated cells and those can not divide. Meristematic cells mature and evolve into permanent cells.
Meristematic tussues are of three types :-
(1) Apical meristem
(2) Lateral meristem
(3) Intercalary meristem
Apical meristems are found in root tips and stem tips of a plant and those are responsible for the root growth and stem growth (growth in height).
Lateral meristems are found in the outermost part of the stem and those responsible for the increment of the girth of the stem or the root.
Intercalary meristems are seen in some plants and are located near the node.
Properties of meristematic cells :-
(1) very active
(2) dense cytoplasm
(3) thin cellulose walls
(4) lack vacuoles
(5) prominent nuclei
We can perform an activity given in NCERT to understand the function of the meristematic tissues.
• Take two glass jars and fill them with water.
• Now, take two onion bulbs and place one on each jar
• Observe the growth of roots in both the bulbs for a few days.
• Measure the length of roots on day 1, 2 and 3.
• On day 4, cut the root tips of the onion bulb in jar 2 by about 1 cm. After this, we will observe that the root stops growing.
This happens due to the fact that the meristematic tissues are present in the root tips. As we cut the tips cell division stops in the root and the root stops growing.
👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇
🔴 Click here to watch the whole playlist on Chapter 6 : 'Tissues' for Class 9 :
• Tissues || in Hindi fo...
👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇👇
Previous video -
🔴 Tissues (Introduction)
• Tissues || in Hindi fo...
**************************************