If two genes are located on the same chromosome and very close together, their inheritance tends to be

• A. They always assort independently.
• B. Inherited together more often.
• C. They are never inherited.
• D. They produce a 9:3:3:1 ratio.

Answer: (B)

Two genes that are very close on the same chromosome are linked. Because they’re so near each other, crossing over between them during meiosis is unlikely, so they tend to be passed on to the next generation as a unit. That means their alleles are inherited together more often than not. Only rarely does recombination separate them, which is why the parental allele combinations appear most frequently. If the genes were far apart or on different chromosomes, independent assortment would dominate and you'd see many more recombined (mixed) allele combinations.