Bacteria — Flashcards

Flashcard 791: Is *Leptospira interrogans* visible on Gram stain?

Answer: No

Extra: *Leptospira* (like most spirochetes) is too thin to be visualized by light microscopy or standard Gram staining. It is visualized using **dark-field microscopy** or **silver stains** (e.g., Warthin-Starry stain).

Flashcard 792: Conjugation of normal bacteria involves transfer of _____ only

Answer: plasmids

Flashcard 793: Which type of immunization has a slow onset? _____

Answer: Active immunization

Flashcard 794: Vancomycin-intermediate staphylococcus aureus (VISA) has an unusually thickened _____

Answer: cell wall

Flashcard 795: Humoral immunity is used to defend against _____-cellular agents

Answer: extra

Flashcard 796: What is the etiology of Syphilis?_____

Answer: Treponema pallidum

Flashcard 797: _____ is a anaerobic spore former that can produce a double zone of hemolysis.

Answer: Clostridium perfringens

Flashcard 798: Why doesn't Rickettsia spp. gram stain well?_____

Answer: Obligate Intracellular bacteria

Flashcard 799: Anthracycline antitumor antibiotics were first isolated from a species of _____ bacteria

Answer: Streptomyces

Flashcard 800: Due to Chlamydia spp. being obligate intracellular bacteria, they gram stain _____

Answer: poorly (well or poorly)