Two genes that are on the same chromosome can assort independently in which of the following cases?

• A. They are located very close together on the chromosome, preventing crossing over.
• B. They are located far apart on the chromosome, allowing crossing over to occur between them during meiosis.
• C. They are on homologous chromosomes but not on the same chromatid.
• D. They are always inherited together because they are on the same chromosome.

Answer: (B)

Verified step by step guidance

1. Understand the concept of gene linkage: Genes located on the same chromosome are said to be linked and tend to be inherited together because they are physically connected.
2. Recall that independent assortment typically applies to genes on different chromosomes or genes far apart on the same chromosome, where crossing over can separate them.
3. Recognize that when two genes are very close together on the same chromosome, crossing over between them is rare, so they do not assort independently.
4. Identify that if two genes are far apart on the same chromosome, crossing over during meiosis can occur between them, allowing the genes to assort independently.
5. Conclude that independent assortment of genes on the same chromosome happens only when crossing over can separate them, which requires the genes to be located far apart.