Question 1

Which of the following best describes a macronutrient in microbial metabolism?

Accepted Answer

A nutrient required in large amounts for cell growth and function

Question 2

Which element is the most abundant in an E. coli cell by dry weight?

Accepted Answer

Carbon (C)

Question 3

Autotrophs differ from heterotrophs in their source of which essential element?

Accepted Answer

Carbon

Question 4

Which type of laboratory media contains compounds that selectively inhibit the growth of some microbes but not others?

Accepted Answer

Selective media

Question 5

What is the primary function of vitamins in microbial metabolism?

Accepted Answer

They function as coenzymes in metabolic reactions

Question 6

Which of the following is a trace element required by most microorganisms for electron transport?

Accepted Answer

Iron (Fe)

Question 7

A pure culture in microbiology refers to:

Accepted Answer

A culture containing only a single kind of microbe

Question 8

Which macronutrient is a key component of nucleic acids and phospholipids?

Accepted Answer

Phosphorus (P)

Question 9

Which of the following is NOT a function of magnesium (Mg) in microbial cells?

Accepted Answer

Serving as a major energy source

Question 10

Which statement about complex media is correct?

Accepted Answer

It is composed of digests of chemically undefined substances

Question 11

Which of the following best explains why agar is preferred over gelatin as a solidifying agent in microbial culture media?

Accepted Answer

Agar remains solid at higher incubation temperatures

Question 12

Which macronutrient is required for the synthesis of sulfur-containing amino acids and coenzyme A?

Accepted Answer

Sulfur (S)

Question 13

Which of the following is a plausible consequence of omitting iron (Fe) from a microbial growth medium?

Accepted Answer

Defective electron transport and energy generation

Question 14

Which type of media would you use to distinguish between bacteria that ferment lactose and those that do not?

Accepted Answer

Differential media

Question 15

Which of the following elements is NOT considered a macronutrient for microbial growth?

Accepted Answer

Iron (Fe)

Question 16

Which of the following best describes the role of potassium (K) in microbial cells?

Accepted Answer

Required for enzyme activity

Question 17

A student prepares a medium using yeast extract and peptone. What type of medium is this?

Accepted Answer

Complex medium

Question 18

Which of the following is a plausible reason for adding additional nutrients to a complex medium?

Accepted Answer

To support the growth of nutritionally demanding organisms

Question 19

Which of the following is a micronutrient required by some marine microbes?

Accepted Answer

Sodium (Na)

Question 20

Which of the following best describes the function of growth factors in microbial metabolism?

Accepted Answer

They are organic compounds required in small amounts for growth

Microbial Metabolism: Nutritional Requirements and Laboratory Culture

Study Guide - Practice Questions