What are spores? Name at least three types of spores. (SHORT ANSWER QUESTIONS) (2MARK)

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Answer :- Spores are asexually reproducing bodies produced inside the sporangia. They germinate to produce new individuals. The different kinds of spores are - zoospores, sporangiospores and chlamydospores.

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CLASSIFICATION Division : Bryophyta Class     : Hepaticopsida Order     : Marchantiales Family   : Marchantiaceae Genus   : Marchantia MORPHOLOGICAL FEATURES OF THE THALLUS- 1. The main plant body is gametophytic thallus. Gametophyte is small, well developed and  autotrophic. 2. The plant body is dorsiventral, the dorsal surfaces is dark green having a distinct midrib and  dichotomously branched. 3. The ventral or the lower surface bear numerous rhizoids and scales. 4. The rhizoids are unicellular and branched structures meant for anchorage and absorption. They  may be smooth walled or tuberculated (bearing peg-like projections). 5. The scales are purplish multicellular structures which protect the thallus from the dessication  by secreting the mucilage. 6. The dorsal surface also bears small gemma cups on the mid ribs. Inside the gemma cups many  erect stalked gemmae are present which helps in vegetative reproduction of Marchantia. 7. Sexual reproduction is oogamous. The male reproduc
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