Massachusetts Esthetics Practice Exam 2025 – Complete Study Guide

Microorganisms is a broad term that encompasses a variety of microscopic organisms, including those that have characteristics of both plant and animal life. This inclusive definition captures various groups, notably protozoa, which are commonly recognized for their animal-like behavior and nutritional habits, and algae, which possess plant-like traits. Understanding micro-organisms as a collective category allows for a better comprehension of their diverse functions and roles in different environments.

The other choices focus on specific types of microorganisms. Viruses are distinct entities that lack cellular structure and cannot be classified as either plants or animals. Bacteria are single-celled organisms that exhibit characteristics of living organisms but generally do not fit the definition of possessing both plant and animal traits. Protozoa specifically represent one category of microorganisms with animal-like characteristics but do not encompass the entire range of organisms that could be considered under the broader definition of microorganisms.