Question

Freshly released human egg has
(A) One Y-chromosome
(B) One X-chromosome
(C) Two X-Chromosome
(D) One X-chromosome and one Y-chromosome

Answer 1

Hint: Freshly released human egg is haploid and contains that chromosome which is common in both parents i.e in both male and female. After fertilization the egg becomes diploid and the term is known as a zygote.

Complete step by step answer:
The egg released is haploid as it has only one X-chromosome and 22 autosomes in it. That one ‘X’ chromosome is from the female parent.
This egg is released at ${ 1 }{ 4 }^{ th }$ day of the menstrual cycle. This process of release of the egg is known as ovulation.
The egg cell is also known as an ovum, is the female sex cell, or gamete, in most anisogamous organisms. The term is employed when the feminine gamete isn't capable of movement (non-motile) . If the male gamete (sperm) is capable of movement, the sort of sexual reproduction is additionally classified as oogamous.
When egg and sperm fuse during fertilization, a diploid cell (the zygote) is made, which rapidly grows into a replacement organism.
Fertilization is the fusion of haploid gametes, egg, and sperm, to make the diploid zygote.
Fertilization can take place naturally and even artificially. Natural fertilization takes place inside the body, while artificial fertilization takes place outside the body, mostly in laboratories. It is also known as in-vitro fertilization. Fertilization is a chance event which means it is not necessary that every time when male gamete is released, it will meet with an egg and produce a zygote.
So, the correct answer is ‘(B) One X-chromosome '.

Note: Females consist of two ‘X’ i.e ‘XX’ chromosomes in the sex chromosome. With the help of meiosis, when gametes are generated, they will be haploid containing only a single ‘X’ chromosome. Another chromosome comes from the father sex chromosome.