Researchers Studying the Rigidity and Fexibility of the Cell Envelope

question 90

Multiple Choice

Researchers studying the rigidity and fexibility of the cell envelope used chemotaxis to measure the ability of microbes to squeeze through tight spaces. E. coli, a gram-negative bacterium, was able to traverse narrower channels than B. subtilis, a gram-positive microbe, even though both cells are the same size when grown without restriction. E. coli has the more fexible cell envelope because _______.

• A) it has fewer flagella
• B) there are fewer protein receptors
• C) it has only a single membrane
• D) lipopolysaccharide has no charge
• E) there is less structural carbohydrate

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Definitions:

Mercury

A heavy metal that can be found in the environment and in certain foods, such as fish, and is toxic to humans in high amounts.

Pesticides

Chemical substances used to eliminate or control pests that threaten agriculture, public health, or comfort.

Iodine

A trace element essential for the synthesis of thyroid hormones, which regulate metabolism, growth, and development.

Foodborne Illnesses

Illnesses resulting from the consumption of contaminated food, typically caused by bacteria, viruses, or parasites.