Massachusetts State Board Esthetics Practice Exam

Which term describes organisms that live on or in another organism without providing any benefits?

1. Fungi

2. Parasites

3. Mutualists

4. Commensals

The correct answer is: Parasites

The term that describes organisms living on or in another organism while providing no benefits to the host is "parasites." Parasites rely on their host for survival and often cause harm in the process. This relationship typically involves the parasite extracting resources from the host, which can lead to various negative effects on the host's health, such as nutrient depletion or disease. In contrast, fungi can have varying interactions with hosts, from detrimental (as in some pathogenic fungi) to beneficial (as in mycorrhizal fungi that help plants). Mutualists are organisms that engage in a symbiotic relationship where both parties benefit, while commensals refer to organisms that live in close association with a host but do not cause harm or provide any benefits. Therefore, the distinguishing feature of parasites is the lack of any benefit to the host and the presence of harm, clearly aligning with the definition provided.