Structural Pest Control Applicator Practice Exam

Diseases are caused by biological agents called ___________________.

1. Parasites.

2. Pathogens.

3. Pests.

4. Infections.

The correct answer is: Pathogens.

Diseases are caused by biological agents known as pathogens. Pathogens include a variety of microorganisms such as bacteria, viruses, fungi, and protozoa, which are responsible for infecting hosts and causing illness. This classification is essential because understanding the specific type of pathogen involved in a disease can help in diagnosing and treating the condition effectively. The other terms, while related to the broader topic of health and disease, do not accurately fit the definition needed in this context. Parasites refer specifically to organisms that live on or inside another organism (the host) and draw nutrients at the host's expense, often leading to parasitic diseases. Pests, on the other hand, are typically organisms that cause annoyance or harm to humans and their activities, often associated with agriculture or hygiene issues but not necessarily linked to disease-causing processes. Infections refer to the invasion and multiplication of pathogens within the body but do not encompass all biological agents involved in disease causation. Hence, pathogens is the precise term that represents the agents responsible for causing diseases.