What is a phenotype?

• A. The genetic makeup of an organism
• B. The observable traits of an organism
• C. The process of cell division
• D. The role of DNA in inheritance

Answer: (B)

A phenotype refers to the observable traits or characteristics of an organism, which can include physical appearance, behavior, biochemical properties, and physiological attributes. These traits are influenced by the organism's genotype, which is its specific genetic makeup, as well as environmental factors. The concept of phenotype is crucial in fields such as genetics and evolutionary biology, as it helps in understanding how traits are expressed and how they can change over generations.

In this context, while the genetic makeup of an organism (genotype) is fundamental to determining its phenotype, the phenotype itself specifically encompasses those traits that can be seen or measured. This distinction is essential for studies involving inheritance and the expression of genetic traits. The process of cell division and the role of DNA in inheritance are important biological concepts but do not relate directly to the definition of phenotype.