Plant Life Cycles And Alternation Of Generations
Chapter Name : Plant Kingdom |
Sub Topic Code : 103_11_03_06_01 |
Topic Name : Plant Life Cycles And Alternation Of Generations |
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Sub Topic Name : Plant Life Cycles And Alternation Of Generations |
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Introduction
The life-cycle of sexually reproducing plants exhibit alternation of generation as there is existence of both haploid gametophyte and diploid sporophyte.
Pre-Requisites:
What are gymnosperms and gymnosperms? what is the difference between the two?
Activity:
Observe some plants like algae, gymnosperms and angiosperms. Figure out which of these are in the diploid sporophyte stage and which in the haploid gametophyte stage.
Real Life Question:
What is alternation of generation and is it a unique character of sexually producing plants?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Sporophyte Gametophyte Haplontic Diplontic Haplo-Diplontic | Diploid spore producing plant body. Haploid gamete producing plant body. Plants in which the haploid gametophyte is dominant. Plants in which the diploid sporophyte is dominant. Plants in which both sporophyte and gametophyte stages almost equally dominant. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Fig. 3.7 of NCERT textbook. | Visual clues for life-cycles. |
Places to visit :
Biology Laboratory, garden, nursery.
Practical examples around us
| Examples | Explainations |
|---|---|
| Rose plant which is an angiosperm, is a diplontic plant. |
What you learn in Theory:
Sexually reproducing plants exhibit alternation of generation.
What you learn in Practice:
Not all plants exist as diploid plants, some do as haploid plant bodies too.