Microbiology Practice Exam

What bacterium is responsible for causing Tuberculosis?

1. Salmonella enterica

2. Mycobacterium tuberculosis

3. Streptococcus pneumoniae

4. Staphylococcus aureus

The correct answer is: Mycobacterium tuberculosis

Mycobacterium tuberculosis is the bacterium responsible for causing tuberculosis (TB). This pathogen is a slow-growing, aerobic bacterium that typically infects the lungs but can also affect other parts of the body. The unique cell wall composition of Mycobacterium tuberculosis, which includes mycolic acids, contributes to its resistance to many common disinfectants and antibiotics, making treatment and control of TB more challenging. The choice of Mycobacterium tuberculosis is particularly significant because it is distinctly recognized for its ability to cause disease, specifically TB, which is characterized by a chronic cough, fever, night sweats, and weight loss. Other bacteria listed do not cause tuberculosis; for instance, Salmonella enterica is known for causing foodborne illnesses, Streptococcus pneumoniae is associated with pneumonia and other respiratory infections, and Staphylococcus aureus is often involved in skin infections and other localized infections. Understanding the specific bacteria associated with various diseases helps in effective diagnosis and treatment.