Parts of a Plant and Seed Germination: CBSE Class 3–5 EVS Guide
Investigating the vital organs of plants and how a tiny dormant seed transforms into a vigorous sprout.
In CBSE Environmental Studies (EVS), children explore how plants function as the green backbone of our biosphere. Every plant consists of two main parts: the Root System (below the soil) and the Shoot System (above the soil).
A seed may appear dry and lifeless, but inside every viable seed lies a living baby plant (embryo) waiting for the right conditions to awaken.
The Two Root Types
• Taproot System: Features a single thick primary root that grows deep into the earth, with smaller secondary branch roots sprouting from its sides. Examples: Mustard, Neem, Mango, Carrot, Radish, and Hibiscus.
• Fibrous Root System: Consists of a cluster of thin, hair-like roots of nearly equal size emerging together from the base of the stem. They spread out horizontally near the surface to prevent soil erosion. Examples: Grass, Wheat, Rice (Paddy), Maize, and Onion.
Three Conditions Required for Germination
Water softens the tough outer protective seed coat (testa) and activates enzymes that turn stored cotyledon starch into soluble sugars.
The living embryo needs oxygen to perform cellular respiration and generate growth energy. Completely waterlogged seeds cannot breathe and will rot.
Enzymes require mild warmth to trigger cellular division. (Note: Most seeds do NOT need sunlight during the very first days underground until their first green leaves emerge!).
✨ Key Takeaways
- The radicle develops into the root; the plumule develops into the shoot and leaves.
- Cotyledons provide built-in food storage for the seedling until it can photosynthesize.
- Taproots have one thick main central root; fibrous roots form a spreading cluster of equal fibers.
- Germination requires water, oxygen, and warmth (light is only needed once green leaves emerge).