Science
(a) Draw a diagram showing spore formation in Rhizopus and label the (i) reproductive and (ii) non-reproductive parts. Why does Rhizopus not multiply on a dry slice of bread?
(b) Name and explain the process by which reproduction takes place in Hydra.
Answer
(a) Diagram showing spore formation in Rhizopus :
- Reproductive part : Sporangium (produces spores).
- Non-reproductive parts : Hyphae and Rhizoids (absorb nutrients and anchor the fungus).
Rhizopus (a fungus) does not multiply on a dry slice of bread because moisture is essential for spore germination so in the absence of moisture, spores remain inactive and cannot grow into new hyphae.
(b) Hydra reproduces by a process called budding.
- Budding : A small bud develops on the body wall of the parent hydra due to repeated cell division at a specific site. This bud grows into a small hydra and, when fully mature, detaches from the parent to live as an independent organism.
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