Question 1

Molecular evidence suggests that:

Accepted Answer

Molecular evidence, such as ribosomal RNA sequences, has shown that Archaea and Eukarya share a more recent common ancestor with each other than either does with Bacteria, indicating that Archaea and Eukarya are more closely related to each other.

Question 2

The term "primitive", when applied to an organism means:

Accepted Answer

The term "primitive" in evolutionary biology refers to organisms that have retained characteristics similar to the earliest members of their taxonomic group, indicating they are evolutionarily closer to the original ancestor of that group.

Question 3

Which of the following statements about microbes and their cell type is FALSE?

Accepted Answer

Protozoa have eukaryotic cells, not prokaryotic cells. This makes statement D false.

Question 4

In what way are viruses distinct from other microbes?

Accepted Answer

Viruses are distinct from other microbes because they are acellular, meaning they do not have a cellular structure. This sets them apart from bacteria, archaea, and eukaryotic microorganisms, all of which have cellular structures.

Question 5

The host range of a particular virus:

Accepted Answer

The host range of a virus refers to the variety of different hosts that a virus can infect, which is determined by the virus's ability to attach to and enter the cells of those hosts.

Question 6

In enveloped viruses, viral specificity is often a consequence of:

Accepted Answer

Viral specificity, particularly in enveloped viruses, is often determined by the envelope glycoproteins. These glycoproteins interact with specific receptors on the host cell's surface, dictating which cells the virus can infect.

Question 7

The eclipse phase of a replicating virus begins immediately following:

Accepted Answer

The eclipse phase of a virus begins immediately following uncoating, which is the process where the viral capsid is removed, exposing the viral genome to the host cell's machinery, allowing replication to begin.

Question 8

Which of the following statements is true about the way that newly-assembled enveloped and non-enveloped are released from a host cell?

Accepted Answer

Enveloped viruses are typically released from the host cell by budding, which allows them to acquire their lipid envelope from the host cell membrane.

Question 9

If a bacteriophage is lysogenic, it means that:

Accepted Answer

In a lysogenic cycle, the bacteriophage infects the host cell but does not immediately replicate. Instead, the viral DNA integrates into the host cell's genome and can be replicated along with the host cell's DNA, potentially for many generations, before entering the lytic cycle where the virus begins to replicate and lyse the host cell.

Question 10

Which of the following is a difference between plant and animal viruses?

Accepted Answer

Plant viruses can move cell to cell through plasmodesmata, structures that connect plant cells, allowing them to infect neighboring cells without needing to exit into the extracellular space. Animal viruses typically must exit one cell and enter another to spread infection.

Question 11

What is the difference between an acute and a chronic viral infection?

Accepted Answer

The answer of What is the difference between an acute...

Question 12

Describe the process of reverse transcription as it occurs in retroviruses.

Accepted Answer

The answer of Describe the process of reverse transcription as...

Question 13

What is different about the way prions reproduce, compared to any other infectious agent?

Accepted Answer

The answer of What is different about the way prions...

Question 14

How does our normal microbiota protect us from some infections by pathogens?

Accepted Answer

The answer of How does our normal microbiota protect us...

Question 15

Into which category of emergent diseases would Zika virus be placed?

Accepted Answer

Zika virus fits into Category 1 because it is a known pathogen that invaded new host populations, particularly evident with its spread to the Americas in the 2015-2016 outbreak.

Question 16

Which of the following statements regarding the use of CRISPR/Cas in gene editing is FALSE?

Accepted Answer

The guide RNA does not associate with introduced foreign DNA to guide it to the insertion spot. Instead, it directs the Cas enzyme to the specific DNA sequence to be edited by being complementary to that sequence, where the Cas enzyme then makes a cut.

Question 17

What exactly is metagenomics and how does it differ from traditional genomics? What has metagenomics shown us about microbial diversity in the environment?

Accepted Answer

The answer of What exactly is metagenomics and how does...

Quiz 1: Understanding Microbes and Their Interactions: From Molecular Evidence to Emerging Diseases