MIC 205A Exam #3 2025 Questions and
Answers
Which of the following statements regarding lichens is FALSE? - ANS Lichens represent a
parasitic relationship between a fungus and an alga or cyanobacterium
Inactivation of a cell's interferon genes would likely have which outcome? - ANS The cell
would no longer alert neighboring cells to respond to a viral infection
What is a component of innate immunity? - ANS Antibody
A virion is composed of - ANS Protein, either RNA/DNA, and possibly lipid
Which causes uncontrolled growth of plant tissue, resulting in a tumor? - ANS Agrobacterium
What definitely set viruses apart from other organisms? - ANS -Viruses are not made of cells
-Viruses replicate by assembly
Viruses may NOT be cultivated in - ANS Cell-free complex media
Which statement regarding bacteria is FALSE? - ANS Lactobacilli can grow easily on nutrient
agar in the presence of oxygen
Pg. 1 Copyright © 2025 Jasonmcconell. ALL RIGHTS RESERVED.
, The Gram-positive rod that is also acid-fast and is a human pathogen is - ANS Myobacterium
tuberculosis
The best possible analogy available below for the way in which variable (V), diversity (D), and
joining (J) antibody gene segments get put together to create the diversity possible in
hypervariable regions is: - ANS To think of the various segments as a bingo game-each
segment is randomly selected, but you're going to need one of each V, D, and J to form a
functional molecule. The right combination varies depending on which antigen is eventually
going to be binding to the molecule (i.e., your bingo card would be the eventual antigen, and
the random calling out of the number/letter combinations would be the forming of the VDJ
hypervariable region).
A bacterium being examined in a microbiology laboratory is found to be lysogenized by phage
A. Which of the following statements is TRUE? - ANS The bacterium is immune to reinfection
by phage A but susceptible to infection by phage B
Which of the following statements about innate immunity is true? - ANS Toll-like receptors
recognize molecules derived from pathogens
Match the following descriptions with the correct groups of viruses - ANS dsRNA viruses:
carry an RNA-dependent RNA polymerase in their virions
Single-stranded (+) sense RNA viruses: viral genome can be translated directly by host
ribosomes
Single-stranded DNA viruses: carry an RNA-dependent DNA polymerase in their virions
dsDNA viruses: replication and gene expression follow the central dogma of molecular biology
Retroviruses: carry an RNA-dependent DNA polymerase in their virions
If your cell-mediated immune response were compromised, which of the following would
happen? - ANS You would be more susceptible to infections by viruses
Skin and mucous membranes (Check all that apply) - ANS -Contain antimicrobial secretions
Pg. 2 Copyright © 2025 Jasonmcconell. ALL RIGHTS RESERVED.
Answers
Which of the following statements regarding lichens is FALSE? - ANS Lichens represent a
parasitic relationship between a fungus and an alga or cyanobacterium
Inactivation of a cell's interferon genes would likely have which outcome? - ANS The cell
would no longer alert neighboring cells to respond to a viral infection
What is a component of innate immunity? - ANS Antibody
A virion is composed of - ANS Protein, either RNA/DNA, and possibly lipid
Which causes uncontrolled growth of plant tissue, resulting in a tumor? - ANS Agrobacterium
What definitely set viruses apart from other organisms? - ANS -Viruses are not made of cells
-Viruses replicate by assembly
Viruses may NOT be cultivated in - ANS Cell-free complex media
Which statement regarding bacteria is FALSE? - ANS Lactobacilli can grow easily on nutrient
agar in the presence of oxygen
Pg. 1 Copyright © 2025 Jasonmcconell. ALL RIGHTS RESERVED.
, The Gram-positive rod that is also acid-fast and is a human pathogen is - ANS Myobacterium
tuberculosis
The best possible analogy available below for the way in which variable (V), diversity (D), and
joining (J) antibody gene segments get put together to create the diversity possible in
hypervariable regions is: - ANS To think of the various segments as a bingo game-each
segment is randomly selected, but you're going to need one of each V, D, and J to form a
functional molecule. The right combination varies depending on which antigen is eventually
going to be binding to the molecule (i.e., your bingo card would be the eventual antigen, and
the random calling out of the number/letter combinations would be the forming of the VDJ
hypervariable region).
A bacterium being examined in a microbiology laboratory is found to be lysogenized by phage
A. Which of the following statements is TRUE? - ANS The bacterium is immune to reinfection
by phage A but susceptible to infection by phage B
Which of the following statements about innate immunity is true? - ANS Toll-like receptors
recognize molecules derived from pathogens
Match the following descriptions with the correct groups of viruses - ANS dsRNA viruses:
carry an RNA-dependent RNA polymerase in their virions
Single-stranded (+) sense RNA viruses: viral genome can be translated directly by host
ribosomes
Single-stranded DNA viruses: carry an RNA-dependent DNA polymerase in their virions
dsDNA viruses: replication and gene expression follow the central dogma of molecular biology
Retroviruses: carry an RNA-dependent DNA polymerase in their virions
If your cell-mediated immune response were compromised, which of the following would
happen? - ANS You would be more susceptible to infections by viruses
Skin and mucous membranes (Check all that apply) - ANS -Contain antimicrobial secretions
Pg. 2 Copyright © 2025 Jasonmcconell. ALL RIGHTS RESERVED.
