Which statement best describes the chromosome theory of inheritance?

Which statement best describes the chromosome theory of inheritance?

• A. A basic principle in biology stating that genes are located on chromosomes and the behavior of chromosomes during meiosis accounts for inheritance patterns.
• B. Genes are located in the cytoplasm and do not involve chromosomes.
• C. Inheritance occurs independently of chromosome behavior during meiosis.
• D. Chromosomes have no role in the transmission of genetic information.

Answer: (A)

The main idea being tested is that genes reside on chromosomes and that what chromosomes do during meiosis explains how traits are passed from parents to offspring. This is the basis of the chromosome theory of inheritance: genes have a physical location on chromosomes, and the way these chromosomes segregate and assort during meiosis produces the patterns of inheritance we observe. This statement is the best because it directly links gene location to the behavior of chromosomes in meiosis. During meiosis, homologous chromosomes separate so that each gamete gets one member of each pair, and independent assortment of different chromosome pairs leads to the variety of combinations seen in offspring. This linkage between chromosome behavior and inheritance patterns aligns with all the classic Mendelian observations and the greater body of genetic evidence, including how alleles on the same chromosome can be inherited together or separated through recombination. The other choices don’t fit because they either place genes outside the chromosomes (in the cytoplasm), claim inheritance is unaffected by chromosomal behavior in meiosis, or deny any role for chromosomes in transmitting genetic information. Those views contradict the experimentally supported understanding that the physical basis of heredity lies in chromosomes and their meiotic movement.

The main idea being tested is that genes reside on chromosomes and that what chromosomes do during meiosis explains how traits are passed from parents to offspring. This is the basis of the chromosome theory of inheritance: genes have a physical location on chromosomes, and the way these chromosomes segregate and assort during meiosis produces the patterns of inheritance we observe.

This statement is the best because it directly links gene location to the behavior of chromosomes in meiosis. During meiosis, homologous chromosomes separate so that each gamete gets one member of each pair, and independent assortment of different chromosome pairs leads to the variety of combinations seen in offspring. This linkage between chromosome behavior and inheritance patterns aligns with all the classic Mendelian observations and the greater body of genetic evidence, including how alleles on the same chromosome can be inherited together or separated through recombination.

The other choices don’t fit because they either place genes outside the chromosomes (in the cytoplasm), claim inheritance is unaffected by chromosomal behavior in meiosis, or deny any role for chromosomes in transmitting genetic information. Those views contradict the experimentally supported understanding that the physical basis of heredity lies in chromosomes and their meiotic movement.