Which statement best describes the organism Bacillus anthracis as given in the material?

Which statement best describes the organism Bacillus anthracis as given in the material?

• A. Gram-negative, aerobic, catalase-negative, non-spore-forming
• B. Gram-positive, aerobic, catalase-positive, non-motile, spore-forming
• C. Gram-positive, anaerobic, catalase-positive
• D. Gram-negative, motile bacillus

Answer: (B)

Bacillus anthracis is best understood by its characteristic combination: it is a Gram-positive rod that grows in the presence of oxygen (aerobic), produces the enzyme catalase (catalase-positive), does not move on its own (non-motile), and forms spores. This cluster of traits—Gram-positive cell wall with thick peptidoglycan, aerobic metabolism, catalase activity, lack of motility, and spore formation—fits B. anthracis precisely. The other descriptions conflict with one or more of these features (for example, Gram-negative or non-spore-forming, anaerobic, or motile), so they don’t describe this organism.

Bacillus anthracis is best understood by its characteristic combination: it is a Gram-positive rod that grows in the presence of oxygen (aerobic), produces the enzyme catalase (catalase-positive), does not move on its own (non-motile), and forms spores. This cluster of traits—Gram-positive cell wall with thick peptidoglycan, aerobic metabolism, catalase activity, lack of motility, and spore formation—fits B. anthracis precisely. The other descriptions conflict with one or more of these features (for example, Gram-negative or non-spore-forming, anaerobic, or motile), so they don’t describe this organism.