Question 1

Which of the following best describes the process and significance of Louis Pasteur's swan-neck flask experiment in disproving spontaneous generation?

Accepted Answer

He demonstrated that sterilized broth in a swan-neck flask remained free of microbial growth unless exposed to airborne microbes, supporting biogenesis.

Question 2

A hospital patient develops a urinary tract infection after catheterization. Which term best describes this infection?

Accepted Answer

Healthcare acquired infection (HAI)

Question 3

Which of the following statements about Gram staining is correct?

Accepted Answer

Gram-positive bacteria appear purple because their thick peptidoglycan layer retains the crystal violet-iodine complex.

Question 4

Which of the following best explains why immersion oil is used with the 100x objective lens in bright field microscopy?

Accepted Answer

Immersion oil decreases the refractive index between the lens and the slide, reducing light loss and increasing resolution.

Question 5

A scientist isolates a bacterium that is rod-shaped and forms chains. What is the correct term for this arrangement?

Accepted Answer

Streptobacilli

Question 6

Which of the following is a key difference between prokaryotic and eukaryotic ribosomes?

Accepted Answer

Prokaryotic ribosomes are 70S, while eukaryotic ribosomes are 80S.

Question 7

A bacterial cell is placed in a hypertonic solution. Predict the outcome and explain the process involved.

Accepted Answer

Water will move out of the cell by osmosis, causing plasmolysis.

Question 8

Which of the following best describes the function of a bacterial capsule?

Accepted Answer

It protects the bacterium from phagocytosis and desiccation.

Question 9

Which of the following statements about the endosymbiotic theory is correct?

Accepted Answer

It proposes that mitochondria and chloroplasts originated from free-living prokaryotes engulfed by ancestral eukaryotic cells.

Question 10

Which of the following is a correct example of binomial nomenclature for a bacterium?

Accepted Answer

Escherichia coli

Question 11

A patient is diagnosed with tuberculosis. Which staining technique would be most appropriate to confirm the presence of Mycobacterium tuberculosis in a sputum sample, and why?

Accepted Answer

Acid-fast stain, because Mycobacterium contains mycolic acid in its cell wall.

Question 12

Which of the following best describes the process of sporulation in bacteria?

Accepted Answer

It is the process by which vegetative cells form endospores in response to harsh conditions.

Question 13

Which of the following statements about biofilms is correct?

Accepted Answer

Biofilms are structured communities of microbes attached to surfaces and embedded in a self-produced matrix.

Question 14

Which of the following best describes the difference between simple diffusion and facilitated diffusion in prokaryotic cells?

Accepted Answer

Facilitated diffusion requires a transport protein, while simple diffusion does not.

Question 15

A microbiologist wants to isolate a pure culture from a mixed sample. Which technique should they use and why?

Accepted Answer

Streak plate technique, because it separates individual cells to form isolated colonies.

Question 16

Which of the following best explains why Mycoplasma bacteria are unique among prokaryotes?

Accepted Answer

They lack a cell wall entirely and have sterols in their plasma membrane.

Question 17

Which of the following is a function of the eukaryotic Golgi apparatus?

Accepted Answer

Modification, sorting, and packaging of proteins and lipids for secretion or delivery to other organelles

Question 18

A scientist observes a eukaryotic cell with numerous cilia covering its surface. Which function do these cilia most likely serve?

Accepted Answer

Movement of the cell or movement of substances along the cell surface

Question 19

Which of the following best describes the role of lysosomes in eukaryotic cells?

Accepted Answer

They contain hydrolytic enzymes that digest macromolecules and cellular debris.

Question 20

Which of the following statements about the scientific method is correct?

Accepted Answer

A scientific law describes a consistent natural phenomenon, while a theory explains the underlying reasons for the phenomenon.

Comprehensive Study Notes: Introduction to Microbiology, Prokaryotic Cells, and Eukaryotic Cells

Guida di studio - Domande di pratica

Study guide - Flashcard