Question

In human males, all the chromosomes are paired perfectly except one. This/These unpaired chromosome is/are:
(I) Large chromosome
(II) Small chromosome
(III) Y chromosome
(IV) X chromosome
A. (i) and (ii)
B. (iii) only
C. (iii) and (iv)
D. (ii) and (iv)

Answer 1

Hint: When no accurate imitation of any of the chromosomes in the typical cell supplement is unpaired, it is known as an effusive chromosome. As we know already, the male organisms have one X and one Y chromosome (XY), while the individuals who are natural females have two X chromosomes. In general, every cell regularly contains 23 sets of chromosomes in all human beings, for an aggregate of 46.

Complete answer:
All human chromosomes are paired, aside from the unpaired sex chromosome in male and mitochondrial DNA. The presence of just a solitary duplicate of genes on the X and Y chromosome in a male prompts significant sex-connected issues. Then again, the 16,500 bp mitochondrial genome is available over 1000 duplicates for each cell, comprising about 0.3% of human DNA.
Consequently, mitochondrial DNA shows heteroplasmy, which implies the proportion of the wild-type allele to a variation allele inside a cell can differ persistently, some of the time bringing about a broad scope of manifestations in any event when just one arrangement variation is included.
So, the correct answer is “Option C”.

Additional Information:
Chromosome 1 is the largest human chromosome, crossing around 249 million DNA building blocks (base matches) and speaking to roughly 8 percent of the all-out DNA in cells. Distinguishing qualities on every chromosome is a functioning territory of hereditary exploration.
Chromosome 21 is one of the 23 sets of chromosomes in people and is the smallest human chromosome. It acts as both a human autosome and chromosome, with 48 million nucleotides (the structure material of DNA) speaking to about 1.5 percent of the total DNA in cells.

Note: In human males, all the chromosomes are matched impeccably apart from one. These unpaired chromosomes are Y-chromosome and X-chromosome. Here, one is an ordinarily measured X chromosome, while the other is a short Y chromosome. There occurs only a single duplication of genes in males, which prompts genetic-disorders. The mitochondrial DNA can show variations in alleles inside the cell. Women have an ideal pair of sex chromosomes, both called X.