Question

Statement 1: The physical distance between two linked genes determines both the strength of linkage and frequency of crossing over between them.
Statement 2: Linked genes show a higher chance of inheritance together if the distance between them is longer.

Choose the correct option

• A. Both the statements are correct
• B. Statement 1 is correct and statement 2 is incorrect
• C. Statement 1 is incorrect and statement 2 is correct
• D. Both the statements are incorrect
  

Answer 1

The correct option is B Statement 1 is correct and statement 2 is incorrect

Linkage is the association of genes. This phenomenon explains that two genes that are located close to each other on a chromosome tend to inherit together. The physical distance between two genes determines both the strength of linkage and frequency of crossing over between the genes. If one gene is distantly located on the chromosome to the other, then there is a high probability of crossing over between the genes resulting in recombination.
Crossovers during meiosis occur at more or less random positions along the chromosome, the distance between the genes determines the effective crossing over. If the genes are closely associated then there is less chance of crossover, hence less chance of recombination. When the genes are distantly located on the chromosome, there is a high probability of crossing over and recombination.