Question

Select the incorrect statement:

• A. Chromosome 1 has the most genes and chromosome Y has the fewest.
• B. Chromosome 21 has the most genes and chromosome Y has the fewest.
• C. Less than 2 percent of the genome codes for proteins.
• D. The functions of over 50 percent of discovered genes are unknown.

Answer 1

The Correct Option is B

The incorrect statement among the given options is: Chromosome 21 has the most genes and chromosome Y has the fewest. 

To understand why this is incorrect, let's examine the facts:

• Chromosome 1 is known to have the most genes, making it the largest in terms of gene content.
• Chromosome Y is the smallest in terms of gene content, containing the fewest genes.
• Chromosome 21, contrary to the incorrect statement, has significantly fewer genes compared to Chromosome 1.
• Less than 2 percent of the human genome codes for proteins, which is accurate as most of the genome consists of non-coding regions.
• The statement that the functions of over 50 percent of discovered genes are unknown is also correct, as ongoing research continues to uncover the roles of many genes.

Conclusively, the statement regarding Chromosome 21 having the most genes is factually incorrect, thus identifying it as the incorrect option.

Answer 2

• Chromosome 1 has the most genes, not Chromosome 21. Chromosome 1 contains approximately 2,000 to 2,500 genes, making it the largest and most gene-rich chromosome.
• Chromosome Y indeed has the fewest genes among the chromosomes. It has about 50 to 200 functional genes, significantly fewer than the other chromosomes.
• Less than 2 percent of the genome codes for proteins is correct. The human genome consists of a large amount of non-coding DNA.
• The functions of over 50 percent of discovered genes are unknown is also true. Many genes have been discovered, but their precise roles in the body are still unclear.