Humber Admissions Practice Test

What is an allele?

1. A combined set of traits

2. The observable effect of a gene

3. Different forms of a gene

4. The process of trait inheritance

The correct answer is: Different forms of a gene

An allele refers to the different forms of a gene that occupy the same position on homologous chromosomes. Each gene can have multiple alleles, which can result in variations in a particular trait. For instance, a gene controlling flower color in plants may have several alleles that result in different colors, such as red, white, and blue. Understanding alleles is crucial for grasping the concepts of heredity and genetic diversity, as they contribute to the variations seen among individuals in a population. The other options do not accurately define an allele. The concept of a combined set of traits refers more broadly to an organism's phenotype, which is distinct from the specific forms of genes. The observable effect of a gene pertains to the phenotype as well, describing how the alleles manifest in physical expression, rather than the alleles themselves. Finally, the process of trait inheritance focuses on how traits are passed from parents to offspring, which is a separate aspect of genetics that involves alleles but is not a definition of what an allele is.