Chapter – 8
How Do Organisms Reproduce?
Q 1. What is the importance of DNA copying in reproduction?
Ans. DNA contains information for inheritance of features from parents to next generation. DNA present in the cell nucleus is
the information source for making proteins. If the information is different, different proteins will be made. Different
proteins will eventually lead to altered body designs.
Q 2. Why is variation beneficial to the species but not necessarily for the individual?
Ans. Variations are useful for the survival of species in changed environmental situations. For example, if a population of
reproducing organisms were suited to a particular niche (well-defined place of abode) and if the niche is drastically altered
the population could be wiped out. However, if some variations were to be present in a few individuals in these
populations, there would be some chance for them to survive. Thus if there were a population of bacteria living in
temperate waters, and if water temperature were to be increased by global warming , most of these bacteria would die,
but few variants resistant to heat would survive and grow further. Variation is thus useful for the survival of species over
time.
Q 3. How does binary fission differ from multiple fission?
Ans. Difference between binary fission and multiple fission:
Binary fission Multiple fission
Spitting of unicellular organisms like Amoeba in to two equal halves during cell division is termed binary
Fission. Division of single-celled organisms such as malarial
parasite in to many daughter cells simultaneously is termed multiple fission.
Q 4. How will an organism be benefited I sit reproduces through spores?
Ans. The spores are covered by thick walls...
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