Which two types of direct examinations are commonly used with a microscope to identify microorganisms?

• A. Agar plate and broth culture
• B. Gram stain and PCR
• C. Wet mount and stained smear
• D. ELISA and Western blot

Answer: (C)

Verified step by step guidance

1. Understand that direct examination methods involve observing microorganisms directly under a microscope to identify their presence and characteristics.
2. Recognize that 'wet mount' is a technique where a drop of liquid sample is placed on a slide and observed immediately under the microscope, allowing visualization of live microorganisms and their motility.
3. Know that 'stained smear' involves fixing microorganisms on a slide and applying specific stains (such as Gram stain) to enhance contrast and reveal structural details, aiding in identification.
4. Differentiate these from other methods listed: agar plate and broth culture are culture techniques, PCR is a molecular method, and ELISA and Western blot are immunological assays, not direct microscopic examinations.
5. Conclude that the two common direct microscopic examination types are 'wet mount' and 'stained smear' because they involve direct visualization of microorganisms under the microscope.