Why Can't Direct Microscopy Be Used to Provide a Presumptive

question 24

Multiple Choice

Why can't direct microscopy be used to provide a presumptive identification of the enteric bacteria?

• A) Some members of the genus Gram stain weakly.
• B) The microscopic characteristics are indistinguishable from other gram-negative bacteria
• C) Some members of the genus do not decolorize well and appear gram positive.
• D) Some members have very thick capsules, and these do not allow the penetration of the Gram stain.

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Definitions:

Noble Gases

A group of chemical elements with similar properties under standard conditions, including being odorless, colorless, monatomic gases with very low chemical reactivity.

Inert Gases

A group of gases which are non-reactive under a set of given conditions, including helium, neon, argon, krypton, xenon, and radon.

Atomic Symbols

Symbols assigned to elements based on their names, usually consisting of one or two letters, where the first letter is always capitalized.

Gallium

A soft, silvery metal used in electronics and low melting point alloys.