Question

In the sexual mode of reproduction________diversities are generated.
A. Lesser
B. Greater
C. Both A and B
D. None of these

Answer 1

Reproduction is one of the most fundamental processes of living beings. It is a biological process by which new individuals are born. There are two modes of reproduction namely, sexual mode of reproduction and asexual mode of reproduction. The law of independent assortment can be seen in the sexual mode of reproduction.

Complete answer: Asexual mode of reproduction is a mode of reproduction where the fusion of gametes does not occur. In this mode of reproduction, chromosome number does not vary. Offsprings produced are exactly similar to that of the parent genetically. Asexual mode of reproduction is achieved by budding, fission, vegetative propagation, fragmentation and parthenogenesis. In an asexual mode of reproduction, spores are formed by the process of mitosis. On the other hand, the sexual mode of reproduction involves the fusion of both male and female gametes. Two parents are involved in this process. Gametes with a single set of chromosomes are fused to form a diploid set of chromosomes. The male gamete may be motile or non-motile i.e. flagella may be present or may not be present. But female gametes are always non-motile. This fusion of different gametes leads to the formation of zygote. The zygote has chromosomes from both the parents, i.e. from mother and father, therefore, the combination of two gametes results in variations that lead to greater diversities. These variations are not only at the phenotypic level but are also present at the genotypic level. Sexual reproduction is of three types: isogamous, anisogamous and oogamous. Maximum variations occur because of the independent assortment and crossing over during the zygote formation.
Hence, the correct answer is option B.

Note: Out of three types of sexual reproduction, Oogamous is the highly advanced type. In isogamous reproduction, both male and female gametes are morphologically and structurally similar. In anisogamous type reproduction, both male and female gametes are morphologically and structurally different.