Which concept explains that two genes on the same chromosome are inherited together more often when they are close together due to reduced crossing-over?

Which concept explains that two genes on the same chromosome are inherited together more often when they are close together due to reduced crossing-over?

• A. Dominant
• B. Mendel's law of segregation
• C. Linkage
• D. Sickle cell disease

Answer: (C)

The idea here is linkage: two genes that sit close to each other on the same chromosome tend to be passed on together more often because the chances of a crossover occurring between them are small. During meiosis, homologous chromosomes exchange segments through crossing-over, which can separate the alleles of nearby genes. When the genes are nearby, such recombination is less likely, so the parental allele combination is inherited as a unit more frequently. As the distance between the genes increases, recombination becomes more likely, and they start to assort more independently, which is why distant or unlinked genes behave more like Mendel’s independent assortment. The other options don’t describe this pattern: dominance is about how traits are expressed, Mendel’s law of segregation concerns how alleles separate for a single gene, and sickle cell disease is a specific inherited condition rather than a pattern of gene inheritance on a chromosome.

The idea here is linkage: two genes that sit close to each other on the same chromosome tend to be passed on together more often because the chances of a crossover occurring between them are small. During meiosis, homologous chromosomes exchange segments through crossing-over, which can separate the alleles of nearby genes. When the genes are nearby, such recombination is less likely, so the parental allele combination is inherited as a unit more frequently. As the distance between the genes increases, recombination becomes more likely, and they start to assort more independently, which is why distant or unlinked genes behave more like Mendel’s independent assortment. The other options don’t describe this pattern: dominance is about how traits are expressed, Mendel’s law of segregation concerns how alleles separate for a single gene, and sickle cell disease is a specific inherited condition rather than a pattern of gene inheritance on a chromosome.