Final answer:
The correct option is 2. Tuberculosis is not caused by a eukaryotic organism but by a bacterium, Mycobacterium tuberculosis; thus, it is the correct option for the disease not caused by a eukaryotic organism among those listed.
Step-by-step explanation:
Eukaryotic Organisms and Human Diseases
Eukaryotic organisms are associated with a variety of human diseases. However, when discerning which of the listed afflictions is not caused by a eukaryotic organism, it is important to understand the causative agents of each. The diseases mentioned–giardiasis, Chagas disease, sleeping sickness, and malaria–are indeed all caused by protozoa, which are single-celled eukaryotic parasites. This leaves us with tuberculosis, which is caused by Mycobacterium tuberculosis, a bacterium, and therefore not a eukaryotic organism. Hence, tuberculosis is the correct answer for the disease not caused by a eukaryotic organism.
Giardiasis is caused by Giardia lamblia, Chagas disease by Trypanosoma cruzi, and sleeping sickness by Trypanosoma brucei. Malaria is caused by the genus Plasmodium. All these are protozoan parasites responsible for significant health issues worldwide, particularly in tropical regions where they are most prevalent. While these diseases are caused by eukaryotic pathogens, tuberculosis, being bacterial in nature, stands out as the exception in the list provided.
It is critical to recognize the types of organisms that cause diseases to understand treatment and prevention strategies better. For eukaryotic organisms, treatments often focus on antiprotozoal medications, while bacterial infections like tuberculosis require antibiotics to effectively treat the disease.