Question 1

Which of the following statements best describes the difference between prokaryotic and eukaryotic cells?

Accepted Answer

Eukaryotic cells have a nucleus surrounded by a membrane, whereas prokaryotic cells lack a true nucleus.

Question 2

A scientist observes a microbe under a microscope and notes it is about 1 µm in diameter. Based on size alone, which type of organism is it most likely to be?

Accepted Answer

Bacterium or archaeon

Question 3

Which of the following is NOT a way microbes benefit humans?

Accepted Answer

Causing infectious diseases

Question 4

The spontaneous generation hypothesis stated that:

Accepted Answer

Living organisms can arise from non-living matter.

Question 5

Which experiment disproved spontaneous generation at the micro level?

Accepted Answer

Pasteur's swan-neck flask experiment

Question 6

During the Golden Age of Microbiology, which of the following advances was NOT made?

Accepted Answer

Proof of spontaneous generation

Question 7

The Germ Theory of Disease led to which of the following improvements in human health?

Accepted Answer

Development of aseptic techniques in medical procedures

Question 8

Which of the following is a major difference between Gram-positive and Gram-negative bacterial cell walls?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer, while Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane.

Question 9

Which cell structure is responsible for motility in bacteria and is involved in the run-and-tumble movement pattern during chemotaxis?

Accepted Answer

Flagella

Question 10

A bacterial colony becomes visible on a streak plate. Approximately how many cells does it take for a colony to be visible?

Accepted Answer

$$10^6$$

Question 11

Which of the following best describes the function of the cytoplasmic membrane?

Accepted Answer

Acts as a selectively permeable barrier controlling the movement of substances into and out of the cell

Question 12

Which of the following statements about plasmids is TRUE?

Accepted Answer

Plasmids are small, circular DNA molecules that can carry antibiotic resistance genes.

Question 13

Which of the following is a function of microtubules in eukaryotic cells?

Accepted Answer

Chromosome separation during mitosis

Question 14

Which of the following is a reason why anthrax can be used as a biological weapon?

Accepted Answer

Anthrax spores are highly resistant to environmental conditions and can be easily dispersed.

Question 15

Which of the following is TRUE regarding the Kirby-Bauer disc diffusion test?

Accepted Answer

It uses antibiotic-impregnated discs to assess bacterial susceptibility by measuring the zone of inhibition.

Question 16

A micropipette labeled 'P1000' shows (from top to bottom) a red 0, black 4, and black 5. What volume is being measured?

Accepted Answer

$$0450\,\mu L$$

Question 17

Which of the following best explains how resistant bacteria become prevalent in a population?

Accepted Answer

Antibiotic use kills susceptible bacteria, allowing resistant bacteria to survive and multiply.

Question 18

Which of the following is NOT a function of a capsule or slime layer in bacteria?

Accepted Answer

Motility

Question 19

Which of the following is a difference between facilitated diffusion and active transport across the cytoplasmic membrane?

Accepted Answer

Active transport moves molecules against their concentration gradient, while facilitated diffusion moves molecules down their concentration gradient.

Question 20

Which of the following is the correct format for a scientific name?

Accepted Answer

Genus species

Microbiology Unit 1 Study Guide – Step-by-Step Guidance

Study Guide - Practice Questions

Study Guide - Flashcards