Kingdom Plantae:
The organisms are autotrophic, Body is highly branched, and reserved food is starch This kingdom is divided into 3 groups
Algae:
- Chlorophyceae (Green Algae)
- Phaeophyceae (Brown Algae)
- Rhodophyceae (Red Algae)
Bryophyta (Amphibious Plants)
- Liverworts
- Moss
Trachophyta
- Pteridophyta (Vascular Cryptogames)
- Gymnosperms (Naked Seeded Plants)
- Angiosperms (Closed Seeded Plants)
Algae:
Chlorophyceae |
Phaeophyceae |
Rhodophyceae |
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Bryophyta:
They include 960 genera and 24000 species. They grow in moist and shady places and some are aquatic. Plant body does not bear vascular tissues and not differentiated into root shoot and leaves. They show alternation of generation that is in the life cycle two forms of the plant body are produced.
Gametophytic generation
- The plant body in this generation produces gametes for sexual reproduction.
- The gametophytic generation is long lived.
- The plant body is green; autotrophic consists of root like structures on the ventral surface called rhizoids and scales
- The plant body bears male and female sex organs where male and female gametes are produced.
- The male sex organs are called antheridia and the female sex organs are called archegonia.
- Water is essential for fertilization.
- No embryo is developed from the development of zygote.
Sporophytic generation:
- When male and female gametes fuse together zygote is formed which develops into sporophytic plant body.
- This generation is short lived.
- The sporophytic plant body is differentiated into foot seta and capsule.
- Within capsule of saprophyte spores are produced by meiosis division in spore mother cells. Eg. Marchantia, Funaria
- Read notes on Marchantia - External, Internal Structure and Reproduction
- Read notes on Funaria - External, Internal Structure and Reproduction
Pteridophyta:
They are truly land plants that grow well in moist shady cool places. The plant body is sporophyte, which is differentiated into leaf stem and roots. The sporophyte is the dominant stage in the life cycle. Which is completely independent attheadult stage? They are well-developed vascular plants therefore; they are also called vascular cryptogams. The spores on germination give rise to gametophytic phase, which is short lived. The gametophytic phase is autotrophic and independent. The water is essential for fertilization. Alternation of generation takes place.
Gymnosperm:
Gymnosperms are exposed seeded evergreen plants. They are considered as the earliest plants on the earth after pteridophyta .there are about 70 genera and 725 species. The plant body is sporophytic and differentiated in to root stem and leaves. They are heteroporous.
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