A Level Biology Practice Exam

What is a phylum in biological classification?

1. A major division of a kingdom

2. The smallest taxonomic group

3. All organisms living in the same habitat

4. A type of viral classification

The correct answer is: A major division of a kingdom

A phylum is indeed a major division of a kingdom in biological classification. In the hierarchical system of taxonomy, it is categorized as one of the higher levels, situated between the kingdom and class. This level groups organisms based on shared characteristics, such as body plans or evolutionary traits. For example, in the animal kingdom, the phylum Chordata encompasses all animals with a notochord, which includes fish, birds, mammals, and reptiles. This designation allows biologists to organize and study the diversity of life in a structured way, facilitating communication and understanding of biological relationships among different groups of organisms.