Molecular Basis of Inheritance
Nucleic acids are long polymers of nucleotides. While DNA stores genetic information, RNA mostly helps in transfer and expression of information. DNA, being chemically and structurally more stable, is a better genetic material. However, RNA is thought to have evolved first. DNA replicates semiconservatively. During transcription, one strand of DNA acts as template to direct the synthesis of complementary RNA. The genetic code is read again on the principle of complementarity by tRNA, which acts as an adapter molecule. Protein synthesis is done by ribosomes. Both transcription and translation are energetically very expensive processes. Regulation of gene expression refers to a very broad term that may occur at various levels. The genes in a cell are expressed to perform a particular function or a set of functions. Human Genome Project was a mega project that aimed to sequence every base in human genome. Many new areas and avenues have opened up as a consequence of the project.
The human Y chromosome has _______ number of genes.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 231
The Human Genome Project found how many genes lie on each chromosome. The numbers differ a lot. Chromosome 1 has the most genes, 2968. The Y chromosome has the fewest, 231.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
NCERT Extract:
Salient Features of Human Genome – “Some of the salient observations drawn from human genome project are as follows:”
Salient Features of Human Genome – “… (viii) Chromosome 1 has most genes (2968), and the Y has the fewest (231).”