Question

Chiasma shows the sites of
 A) Spindle formation
B) Synapsis
C) Crossing over
D) None of the above

Answer 1

Hint:Meiosis is a sort of cell division of germ cells in sexually reproducing organisms and life forms used to deliver the gametes, for example, sperm or egg cells.

Complete answer:
 The cycle of meiosis includes two rounds of division that at last outcome in four cells with just one duplicate of each paternal and maternal chromosome (haploid). Moreover, before the division, genetic material from the paternal and maternal copies of every chromosome is crossed over, making new combinations of code in every chromosome.
Prophase 1 of Meiosis is the principal phase of meiosis and is characterized by five different stages; Leptotene, Zygotene, Pachytene, Diplotene and Diakinesis. Prophase 1 is basically the crossing over and recombination of genetic material between non sister chromatids, this outcomes in the hereditarily identical, haploid daughter chromatid cells.

A chiasma is where two homologous non-sister chromatids trade genetic material during chromosomal crossover during prophase I of Meiosis which is the explanation for recombination and variations among organisms.
Each parent cell has sets of homologous chromosomes, one homolog from the male(father) and one from the female(mother). In meiosis, the maternal and paternal chromosomes can be rearranged into the daughter cells in various combinations. This confirms genetic variations in sexually reproducing living beings and organisms. Further genetic variation originates from crossing over, which happens during prophase I of meiosis.

In this way, the correct answer for this question is C, i.e. 'crossing over'

Note: During fertilization, the haploid cells delivered by meiosis from a male and female will fuse to make a cell with two duplicates of each chromosome, the zygote.Charisma is the explaination for the recombination and variations among organisms