Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Germination is the process by which a seed develops into a new plant or seedling under favorable conditions.
Three essential conditions for germination are: Moisture (), Air (), and Warmth (suitable temperature).
The Seed Coat (Testa) is the outer protective layer that softens when it absorbs .
The Cotyledons (seed leaves) store food for the growing embryo. Some seeds have one (Monocots) and some have two (Dicots).
The Embryo consists of the Radicle, which grows downwards to become the root, and the Plumule, which grows upwards to become the shoot.
During the early stages, the seedling depends on the food stored in the cotyledons until it develops green leaves to perform photosynthesis.
📐Formulae
💡Examples
Problem 1:
Rohan placed some bean seeds in a bowl of water and kept them in a refrigerator. After 5 days, he noticed the seeds did not germinate. Why?
Solution:
The seeds did not germinate because they lacked 'Warmth'.
Explanation:
While the seeds had moisture () and some air (), the low temperature inside the refrigerator prevented the biological processes required for germination. Seeds need a specific temperature range to activate growth.
Problem 2:
What happens to the cotyledons after the seedling grows its first true leaves?
Solution:
The cotyledons eventually shrivel and fall off.
Explanation:
Once the plumule develops into a shoot with green leaves, the plant begins to make its own food through photosynthesis. At this point, the stored food in the cotyledons is exhausted, causing them to dry up and fall off.
Problem 3:
If a farmer sows seeds and only grow into seedlings, what is the germination percentage?
Solution:
The germination percentage is .
Explanation:
Using the formula , we calculate the success rate of the seeds.