Hiding in the Heart of A Seed
The process of sprouting of small plants from the embryo of a seed on arrival of favourable conditions is called seed germination. Seeds which do not germinate even after being provided with all the conditions necessary for germination are called dormant seeds and the phenomenon is termed as dormancy.
When a seed germinates, the portion above the cotyledon that forms future shoots is called plumule and the portion below the cotyledon that forms the future roots is called radicle.
1. Conditions Necessary for Seed Germination
(i) Water: The mature seeds are often dry. In order to provide sufficient amount of moisture to the seeds, water is necessary.
(ii) Oxygen: It is necessary for the metabolism of the germinating seed.
(iii) Temperature: It is necessary to maintain optimum temperature as it affects the growth rate of the plant.
• Take a wooden block and tie three bean seeds to it.
• Keep the block in such a way that the upper seed is completely above the water, the lower seed is completely submerged in water and the middle seed is half submerged in water.
• Keep the beaker at a temperature of 25°C to 30°C for a few days.
• The seed at the top does not germinate.
• The seed at the bottom does not germi…
To view the complete topic, please