Meristematic Tissues
6 Minutes
Meristematic tissues in plants explained for students, covering cell division, differentiation, and the three types of meristems. A science lesson in English.
- How cells join to form tissues, like threads woven into cloth
- How cell division and differentiation work in growing plants
- Apical, intercalary, and lateral meristems and their functions
What this lesson teaches
Meristematic tissue is a specialized plant tissue made of rapidly dividing cells that drives the growth and development of plants. These cells continuously divide, change their shapes and functions over time, and eventually mature into permanent tissues that settle into specific roles inside the plant.
How cells build tissues and organs
Every living part of a plant or animal, from eyes and ears to roots and stems, begins with a tiny cell. Just like individual threads are woven together to create a piece of cloth, many cells join together to form a tissue. Different tissues then combine in various ways to make up distinct body parts, carrying out the necessary jobs needed to keep the organism alive and growing.
Cell division versus cell differentiation
- Cell division occurs when a parent cell splits into two or more identical cells with no differences between them.
- Cell differentiation occurs when dividing cells change their structure and function so they no longer look or act like the original cell.
- Meristematic cells initially act by dividing repeatedly to produce new cells.
- As these dividing cells mature, they differentiate and turn into permanent tissues that remain fixed inside the plant.
- Meristematic cells can have varied shapes, including round, oval, polygonal, and rectangular forms.
The three types of meristems
- Apical meristem is found at the tips of roots and stems, driving upward growth and spreading roots deeper into the soil.
- Intercalary meristem is located at the internodes, which are the spaces between the leaf-sprouting nodes.
- Lateral meristem is situated along the sides of the plant stem, enabling the plant to expand outward rather than just growing up or down.
Examples of meristem action in nature
Green gram seeds wrapped in a damp cloth sprout new growth overnight because of active apical meristems at their tips. When grazing cows eat the top half of grass blades, intercalary meristems in the internodes allow the grass to grow back fully within a few days. Lateral meristems are responsible for the thickness and sturdiness of large plants, allowing trees like the banyan to become wide and strong.