Four Flasks Are Prepared with a Broth That Supports Microbial

question 3

Multiple Choice

Four flasks are prepared with a broth that supports microbial growth. Broth A is boiled and then sealed to prevent the entry of air. Broth B is boiled and left open to the air. Broth C is boiled and left open, but the flask is fitted with an S-shaped neck. Broth D is boiled, left open to the air, and fitted with an S-shaped neck, but after two days the neck is removed. If the broths are examined after four days, which ones will contain living microorganisms?

• A) All broths will contain microorganisms.
• B) None of the broths will contain microorganisms.
• C) broths B & D
• D) broths A & C
• E) broths B, C & D

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Definitions:

Avoidance Behavior

Actions taken to prevent or avoid the occurrence of an unpleasant stimulus or scenario.

Delay

A period of time before an event or action takes place.

Aversive Event

An unpleasant or harmful event or stimulus that an organism seeks to avoid or escape.

Avoidance Response

A behavior aimed at preventing an unpleasant or harmful event before it occurs.