Question

The events in sexual reproduction are
(i) pre-fertilisation
(ii) fertilization
(iii) post-fertilisation
The sequential order of their occurrence is

A) (ii)-(i)-(i)
B) (ii)-(ii)-(i)
C) (i)-(ii)-(iii)
D) (i)-(iii)-(iv)

Answer 1

Gametogenesis is known as the process of creation of male and female gametes. Gametes are cells that are haploids. The haploid parental body is found in species like monerans, algae, fungi and bryophytes.

Complete Answer:
Sexual reproduction is a form of reproduction involving a complicated life cycle in which a particular set of chromosomes (haploid) integrates a gamete (including a sperm or egg cell) with another to create an organism consisting of cells with two pairs of chromosomes (diploid). In multicellular eukaryotes, like mammals, fungi and plants, sexual reproduction is the most prevalent life cycle.

Now, let us find the solution from the options-
- The basic events of sexual reproduction, considering their anatomical, morphological, and physiological distinctions, are the same.

They should categories these occurrences as follows:
- Events of pre-fertilization: All preparatory changes before gametes are combined are considered events of pre-fertilization. Gametogenesis and gamete transition comprise both.
- Fertilization: To create a zygote, the merger of two whole gametes (one male and one female).
- Post-fertilization: All events that take place after the synthesis of gametes throughout sexual reproduction are known as post-fertilization events.

Thus, the correct answer is option (C) (i)-(ii)-(iii).

Note: The fertilisation process occurs outside of the organism body, i.e. in the ocean, in most marine species, e.g. fish, algae, and in amphibians. External fertilization is considered this kind of gametic fusion.