Which chromosome of human genome contains least number of genes?a)Chromosome 12b)Chromosome Xc)Chromosome Yd)Chromosome 1Correct answer is option 'C'. Can you explain this answer?

Question

Answer

Chromosome 1 contains a maximum of 2968 genes and chromosome y contains the minimum 231 genes.

Answer

Chromosomes are thread like structures of DNA and proteins that carry genetic information of organisms in the form of genes. The human chromosomes with least number of genes is Your chromosome.
Option ' C ' is correct answer.

Answer

Chromosome Y contains the least number of genes in the human genome.

Firstly, it is important to understand the structure and organization of chromosomes in the human genome. Chromosomes are thread-like structures located in the nucleus of every cell and they carry the genetic information in the form of genes. Each chromosome consists of a long DNA molecule that is tightly coiled and packed with proteins.

Chromosome Y is one of the two sex chromosomes in humans, with the other being chromosome X. While females have two X chromosomes (XX), males have one X and one Y chromosome (XY). The Y chromosome is smaller in size compared to the X chromosome and carries fewer genes.

Here are the reasons why chromosome Y contains the least number of genes:

1. Degeneration and loss of genes: Throughout evolution, the Y chromosome has undergone a process called degeneration, leading to the loss of genes. This degeneration is thought to have occurred due to the lack of recombination between the X and Y chromosomes during meiosis in males. Over time, many genes on the Y chromosome have become non-functional or have been lost completely.

2. Lack of recombination: Recombination is a process where genetic material is exchanged between homologous chromosomes during meiosis. It contributes to genetic diversity and helps in repairing damaged DNA. However, recombination does not occur between the X and Y chromosomes because they have different gene content. This lack of recombination limits the opportunity for genes on the Y chromosome to acquire new genetic material, leading to a reduction in gene number over time.

3. Essential genes only: Despite the loss of genes, the Y chromosome still contains a few essential genes that are necessary for male sexual development and fertility. These genes include the SRY gene, which triggers the development of male characteristics during embryogenesis, and genes involved in spermatogenesis.

In conclusion, chromosome Y contains the least number of genes in the human genome due to degeneration and loss of genes over evolutionary time, lack of recombination with the X chromosome, and the presence of only essential genes related to male sexual development and fertility.

Answer

Answer

There are 23 pairs of chromosome in human cells. The chromosome Y is the smallest and contain least number of gene (231) and chromosome 1 contain highest number of gene (2968).

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