Question 1

Which of the following statements best describes the theory of biogenesis?

Accepted Answer

Living organisms arise only from preexisting living cells.

Question 2

A scientist discovers a new microorganism that is unicellular, lacks a nucleus, and has peptidoglycan in its cell wall. To which group does this organism most likely belong?

Accepted Answer

Bacteria

Question 3

Which of the following is a correct application of binomial nomenclature for naming microorganisms?

Accepted Answer

Staphylococcus aureus

Question 4

A patient presents with a fungal infection. Which of the following characteristics would help you distinguish the causative agent as a fungus rather than a bacterium?

Accepted Answer

Presence of chitin in the cell wall

Question 5

Which of the following best explains why viruses are not classified as living organisms?

Accepted Answer

They cannot carry out metabolic processes independently.

Question 6

A bacterial cell is observed to have a thick, waxy cell wall and is resistant to desiccation and many antibiotics. Which structure is most likely responsible for these properties?

Accepted Answer

Endospore

Question 7

Which of the following equations correctly represents the process of conjugation in bacteria, where a plasmid is transferred from a donor (F+) to a recipient (F-) cell?

Accepted Answer

$$ F^+ + F^- \rightarrow 2F^+ $$

Question 8

A patient is diagnosed with a disease caused by a nematode. Which of the following best describes nematodes?

Accepted Answer

Round, unsegmented worms with a complete digestive tract

Question 9

Which of the following is a medically important protozoan that causes malaria?

Accepted Answer

Plasmodium

Question 10

A virus is found to have a single-stranded RNA genome and an envelope. Which of the following best describes its structure?

Accepted Answer

It has a protein capsid, a lipid envelope, and RNA as its genetic material.

Question 11

Which of the following best describes the lytic cycle of a bacteriophage?

Accepted Answer

The virus enters the host cell, replicates, and causes cell lysis to release new virions.

Question 12

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 13

A patient is infected with a DNA oncogenic virus. Which of the following is a possible outcome of this infection?

Accepted Answer

The virus integrates its DNA into the host genome, potentially leading to uncontrolled cell division.

Question 14

Which of the following best describes the function of the glycocalyx in eukaryotic cells?

Accepted Answer

It is involved in cell recognition and protection.

Question 15

A mutation changes a codon from UAU (tyrosine) to UAA (stop codon). What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 16

Which of the following best explains why prions are unique infectious agents?

Accepted Answer

They are composed solely of protein and lack nucleic acids.

Question 17

A patient is diagnosed with a persistent viral infection. Which of the following best describes this type of infection?

Accepted Answer

The virus remains in the host for long periods, often with ongoing production of low levels of virus.

Question 18

Which of the following best describes the role of arthropods in the transmission of microbial diseases?

Accepted Answer

They act as vectors, transmitting pathogens between hosts.

Question 19

A bacterial cell is exposed to a chemical mutagen that causes the insertion of a single nucleotide into a gene. What is the most likely result of this mutation?

Accepted Answer

Frameshift mutation

Question 20

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

Accepted Answer

Transfer of bacterial DNA from one cell to another via a bacteriophage

BIO 225 Unit 1: Microbiology Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards