Which of the following best describes a genotype?

The best description of a genotype is the underlying genetic makeup of an organism. A genotype refers to the specific alleles or genetic variants that an organism carries, which can be composed of dominant and recessive traits. This genetic composition is responsible for the potential traits and characteristics that may be expressed in the organism.

The genotype forms the basis for hereditary transmission and influences various traits, ranging from physical features to susceptibility to certain diseases. For instance, an individual may carry alleles for eye color, height, or other traits, regardless of whether those traits are visually apparent.

In contrast, the physical appearance of an organism pertains to its phenotype, which is influenced by both its genotype and environmental factors. The process of phenotypic expression refers to how the genotype manifests as observable traits, and a diagram used for genetic crossing, often called a Punnett square, helps visualize potential genetic combinations between parents. Each of these alternative definitions highlights aspects related to genetics but does not specifically define what a genotype is, which is fundamentally about the internal genetic information.