Question 1

Which of the following is a unique feature of Gram-negative bacterial cell walls that distinguishes them from Gram-positive cell walls?

Accepted Answer

Outer membrane containing lipopolysaccharide (LPS)

Question 2

A scientist observes a bacterium with a spiral shape and flexible movement. Which term best describes this organism's morphology?

Accepted Answer

Spirochete

Question 3

Which cellular structure is responsible for the transfer of genetic material between bacteria during conjugation?

Accepted Answer

Pili

Question 4

According to Koch’s postulates, which step is necessary to demonstrate that a specific microorganism causes a particular disease?

Accepted Answer

The microorganism must be isolated from a diseased organism and grown in pure culture.

Question 5

Which scientist is credited with developing antiseptic techniques in surgery, significantly reducing infection rates?

Accepted Answer

Joseph Lister

Question 6

Which of the following is evidence supporting the endosymbiotic theory for the origin of mitochondria and chloroplasts?

Accepted Answer

Both organelles have double membranes and their own circular DNA.

Question 7

A virus with a lipid envelope is most likely to be:

Accepted Answer

More susceptible to drying and detergents than a non-enveloped virus

Question 8

Which enzyme allows aerobic bacteria to neutralize hydrogen peroxide, a toxic oxygen product?

Accepted Answer

Catalase

Question 9

A bacterium is classified as a thermophile. Which temperature range would best support its growth?

Accepted Answer

45–80°C

Question 10

Which of the following correctly describes the function of bacterial endospores?

Accepted Answer

Enable survival under harsh environmental conditions

Question 11

Which of the following is a characteristic of eukaryotic cells but NOT prokaryotic cells?

Accepted Answer

Membrane-bound nucleus

Question 12

Which of the following is a cytopathic effect observed in cells infected by viruses?

Accepted Answer

Cell lysis and inclusion bodies

Question 13

A bacteriophage infects a bacterial cell and integrates its DNA into the host genome. This process is known as:

Accepted Answer

Lysogenic cycle

Question 14

Which of the following is NOT a correct scientific name according to binomial nomenclature rules?

Accepted Answer

bacillus subtilis

Question 15

Which of the following organic molecules is primarily responsible for storing genetic information?

Accepted Answer

Nucleic acids

Question 16

Which eukaryotic organelle is responsible for ATP production through cellular respiration?

Accepted Answer

Mitochondrion

Question 17

A patient presents with ringworm, a fungal infection. Which type of eukaryotic microbe is responsible for this disease?

Accepted Answer

Fungus

Question 18

Which of the following best describes a prion?

Accepted Answer

A proteinaceous infectious particle lacking nucleic acids

Question 19

A virus is cultivated in a laboratory using a bacterial host. This process is most likely used for which type of virus?

Accepted Answer

Bacteriophage

Question 20

A microbe is classified as an obligate anaerobe. Which equation best represents the absence of oxygen in its metabolism?

Accepted Answer

$\mathrm{C_6H_{12}O_6} \rightarrow 2\mathrm{C_2H_5OH} + 2\mathrm{CO_2}$

Unit 1 Study Guide: Microbiology Fundamentals (Chapters 1, 3, 4, 5, 6)

Study Guide - Practice Questions