Question

Two allelic genes are located on

• A. Two homologous chromosomes, each having one gene
• B. Two non-homologous chromosomes
• C. Any two chromosomes with one each
• D. Same chromosome​

Answer 1

The correct option is A

Two homologous chromosomes, each having one gene

The correct option is A :

Explanation for the correct option:

Option A:

1. It is a variant of a gene that is occasionally found on the same chromosome at the same place or genetic locus.
2. Each pair of alleles reflects the genotype of a certain gene, and each allele contributes to the organism's phenotype, which is defined as the outward appearance of the organism.
3. On two homologous chromosomes, two allelic genes are found.
4. One maternal and one paternal chromosome are joined within the cell after fertilization to form homologous chromosomes.
5. They have identical genes on each chromosome, which allows a pair of chromosomes to align precisely before separation during meiosis.
6. These chromosomes facilitate the recombination and segregation of genetic material from the mother and father into new cells during the events of meiosis and mitosis.

Option B:

Non-homologous chromosomes do not have the same pairings, and their form, which includes the length of the arms and the position of the centromere, differs from that of homologous chromosomes, and they do not couple up during the meiotic process.

Option C:

1. Chromosomes are thread-like structures that are part of an organism's genetic material.
2. They are a lengthy DNA molecule that is present in most eukaryotic organisms and involve the packing of proteins known as histones.

Option D:

Two allelic genes are not located on the same chromosomes.

Final Answer: Two allelic genes are located on Two homologous chromosomes, each having one gene