A Level Biology Practice Exam

Which of the following terms refers to a group of organisms that can interbreed?

1. Genus

2. Species

3. Subclass

4. Phylum

The correct answer is: Species

The term that refers to a group of organisms that can interbreed is "species." In biological classification, a species is defined as a group of individuals that are capable of mating and producing fertile offspring under natural conditions. This definition underscores the reproductive isolation that distinguishes one species from another, meaning that members of different species do not typically interbreed or, if they do, their offspring are generally infertile. The importance of this definition is clear in ecology and evolution, where understanding species boundaries helps scientists study biodiversity, conservation efforts, and the processes of natural selection and speciation. In contrast, the terms genus, subclass, and phylum refer to higher levels of classification that encompass multiple species, making them broader categories that do not focus specifically on interbreeding capabilities.