Linkage is

Options

A. Stronger between genes located far away from each other upon the chromosome
B. Stronger between genes located close together upon the chromosome
C. Strength of linkage is not dependent upon the distance between the genes
D. It depends upon the nature of the concerned genes

Answer

**Step-by-Step Text Solution:**

1. **Definition of Linkage**: Linkage refers to the tendency of genes that are located close to each other on a chromosome to be inherited together during the process of meiosis. This is because they are physically close, reducing the likelihood of crossing over occurring between them.

2. **Distance and Linkage**: The strength of linkage is stronger between genes that are located close together on a chromosome. When genes are close, the probability of crossing over (the exchange of genetic material between homologous chromosomes) is lower.

3. **Crossing Over and Frequency**: As the distance between genes increases, the probability of crossing over increases. This means that genes that are far apart on a chromosome are less likely to be inherited together, leading to a decrease in linkage.

4. **Incorrect Options Analysis**:
- The first option incorrectly states that linkage is stronger between genes located far apart, which contradicts the definition of linkage.
- The third option suggests that the strength of linkage is not dependent on the distance between genes, which is incorrect since distance is a crucial factor.
- The fourth option implies that linkage depends on the nature of the genes involved, which is also incorrect; it primarily depends on their distance on the chromosome.

5. **Conclusion**: The correct understanding is that linkage is stronger between genes that are located close together on the chromosome, and as the distance between the genes increases, the likelihood of crossing over increases, leading to a decrease in linkage.