Question

Students were discussing inheritance in science class. They came up with the following four statements describing genes. Which of their explanations is correct?

A. Chromosomes are made up of genes that provide instructions for the traits that get passed on from parents to offspring.
B. Genes are made up of chromosomes, and they provide instructions for the traits that get passed on from parents to offspring.
C. Chromosomes are made up of genes that determine the behaviors organisms learn throughout their lifetime.
D. Genes are made up of chromosomes, and they determine the behaviors organisms learn throughout their lifetime.

Answer 1

The correct statement is A, which describes that chromosomes are made up of genes that provide instructions for inherited traits. Genes contain the genetic code for proteins and are located on chromosomes, which are passed from parents to offspring. Refuting statement B, genes are not composed of chromosomes; rather, they reside on them.

Step-by-step explanation:

The correct explanation among the choices provided by the students is A. Chromosomes are indeed comprised of genes that carry the necessary instructions for various traits that are passed from parents to offspring. This concept is deeply rooted in the chromosomal theory of inheritance, which indicates that chromosomes, found within the nucleus of cells, act as vectors for genetic information.

Genes are specific sequences of DNA that contain these instructions, coding for the development of traits in an organism. As such, genes do not make up chromosomes but are rather located on the chromosomes. Each chromosome houses many genes, which can come in different versions known as alleles. These alleles can be different for the same gene and are responsible for the diversity seen in the traits of organisms.

The behaviors that organisms learn throughout their lifetime are not determined by genes; these are typically influenced by a combination of genetic predispositions and environmental factors. Therefore, statements C and D are incorrect as they incorrectly suggest that genes determine learned behaviors. Additionally, statement B is incorrect because it incorrectly asserts that genes are made up of chromosomes. The proper relationship is that chromosomes are the larger structures on which genes are located.

Gregor Mendel’s work laid the foundation for understanding how traits are inherited. He proposed that the inheritance patterns are due to the transmission of genes from parents to offspring. According to Mendel, these genes are located on chromosomes, which occur in pairs. Each parent contributes one chromosome to the pair, thereby influencing the offspring’s traits.