Chapter 6: Acellular Pathogens

Question 1

It is a microscopic infectious agent that requires a living host cell to replicate. It is composed of an infection which is a strand of an acellular microorganism.

Answer 1

biological virus

Question 2

A protein shell that encloses the viral genome (DNA or RNA) and has a helical, icosahedral, or complex structure.

Answer 2

capsid

Question 3

It is an additional lipid bilayer surrounding the capsid of some viruses, which is derived from the host cell membrane.

Answer 3

envelope

Question 4

What is the typical size range of viruses?

Answer 4

20 to 300 nanometers

Question 5

It is an organism that transmits the virus from one host to another, spreading viral infections.

Answer 5

Vector

Question 6

A type of vector wherein the virus replicates inside itself before being transmitted to a new host.

Answer 6

Biological Vector

Question 7

What type of vector are mosquitoes which transmit dengue & yellow fever viruses?

Answer 7

Biological Vector

Question 8

A type of vector that carries the virus on its body or mouthparts but does not allow replication inside itself.

Answer 8

Mechanical Vector

Question 9

It is a complete virus particle that is infectious and can infect host cells.

Answer 9

Virion

Question 10

The genetic material of the virus, which can be either DNA or RNA.

Answer 10

Genome

Question 11

What are the two categories of viruses according to general composition?

Answer 11

Naked viruses or Non-enveloped viruses & Enveloped viruses or Viral envelope

Question 12

These are viruses that lack an outer lipid envelope and consist only of a protein capsid and genetic material. They are more resistant to harsh conditions and spread through surfaces, water, or the fecal-oral route.

Answer 12

Naked viruses or Non-enveloped viruses

Question 13

These viruses have a lipid membrane derived from the host cell, making them more fragile but better at evading the immune system. They spread through direct contact, respiratory droplets, or bodily fluids.

Answer 13

Enveloped viruses or Viral envelope

Question 14

A viral capsid shape wherein its proteins form a spiral around the genetic material, which is often RNA.

Answer 14

Helical

Question 15

What is the capsid shape of the Tobacco mosaic virus?

Answer 15

helical

Question 16

A viral capsid shape that is symmetrical and has 20 sides. Its surface is made up of equilateral triangles. This form is incredibly effective and sturdy.

Answer 16

Icosahedral

Question 17

What is the capsid shape of the Poliovirus?

Answer 17

Icosahedral

Question 18

A viral capsid shape that is more complex or asymmetrical, frequently combining icosahedral and helical elements or other structural elements.

Answer 18

Complex

Question 19

What is the capsid shape of the Variola virus?

Answer 19

Complex

Question 20

It is a dynamic and complex field that helps researchers understand the diversity of viruses and track the emergence of new viral strains.

Answer 20

Virus taxonomy

Question 21

Based on the Baltimore classification system, how many groups are viruses classified into?

Answer 21

7

Question 22

In Baltimore classification system, viruses are categorized according to their …

Answer 22

genome type and replication strategy

Question 23

Adenoviruses, Herpesviruses, & Poxviruses belong to which classification of viruses?

Answer 23

Group I: Double-stranded DNA (dsDNA) viruses

Question 24

Most dsDNA viruses replicate using host DNA polymerase, however, Poxviruses replicate in the ____ because of its size.

Answer 24

cytoplasm

Question 25

Where do most RNA viruses that infect animal cells replicate?

Answer 25

Cytoplasm

Question 26

This group converts into dsDNA before transcription. It includes the Parvoviruses.

Answer 26

Group II: Single-stranded DNA (ssDNA) viruses

Question 27

This group requires RNA-dependent RNA polymerase for transcription. It includes the Reoviruses (Rotaviruses).

Answer 27

Group III: Double-stranded RNA (dsRNA) viruses

Question 28

What are the three groups of RNA viruses?

Answer 28

Group III: Double-stranded RNA (dsRNA) viruses, Group IV: Positive-sense single-stranded RNA (+ssRNA) viruses, & Group V: Negative-sense single-stranded RNA (- ssRNA) viruses

Question 29

This group of viruses can be directly translated into proteins.

Answer 29

Group IV: Positive-sense single-stranded RNA (+ssRNA) viruses

Question 30

To which group do Coronaviruses, Flaviviruses (Dengue, Zika), Picornaviruses (Polio, Rhinovirus) belong?

Answer 30

Group IV: Positive-sense single-stranded RNA (+ssRNA) viruses

Question 31

What are the two groups of Reverse Transcribing Viruses?

Answer 31

Group VI: Single-stranded RNA retroviruses (ssRNA-RT) & Group VII: Double-stranded DNA retroviruses (dsDNA-RT)

Question 32

These viruses require RNA-dependent RNA polymerase to convert themselves into +ssRNA before translation.

Answer 32

Group V: Negative-sense single-stranded RNA (- ssRNA) viruses

Question 33

To which classification do Influenza, Measles, Rabies, Ebola belong?

Answer 33

Group V: Negative-sense single-stranded RNA (- ssRNA) viruses

Question 34

These viruses convert RNA into DNA using reverse transcriptase.

Answer 34

Group VI: Single-stranded RNA retroviruses (ssRNA-RT)

Question 35

To which classification do HIV (Human Immunodeficiency Virus), HTLV (Human T-cell Leukemia Virus) belong?

Answer 35

Group VI: Single-stranded RNA retroviruses (ssRNA-RT)

Question 36

These viruses [including Hepatitis B virus (HBV)] use reverse transcription during replication.

Answer 36

Group VII: Double-stranded DNA retroviruses (dsDNA-RT)

Question 37

What are the 2 groups of DNA Viruses?

Answer 37

Group I: Double-stranded DNA (dsDNA) viruses & Group II: Single-stranded DNA (ssDNA) viruses

Question 38

These are viruses that specifically infect and replicate within bacteria or prokaryotes.

Answer 38

Bacteriophages or phages

Question 39

What are the two types of Bacteriophages?

Answer 39

Virulent phages & Temperate phages

Question 40

These bacteriophages have a lytic life cycle during which they take over the cell, reproduce new phages, and destroy the cell through cell lysis.

Answer 40

Virulent phages

Question 41

These bacteriophages can become part of a host chromosome and are replicated with the cell genome until such time as they are induced to make newly assembled viruses.

Answer 41

Temperate phages

Question 42

What are the two life cycles of Temperate phages?

Answer 42

lysogenic and lytic.

Question 43

It is a new virus particle produced by the replication cycle of an existing virus within a host cell.

Answer 43

progeny viruses

Question 44

What type of bacteriophage is the T-even phage?

Answer 44

Virulent phage

Question 45

In this viral life cycle, instead of killing the host, the phage genome integrates into the bacterial chromosome and becomes part of the host.

Answer 45

The Lysogenic Cycle

Question 46

What viral life cycle does lambda phage has?

Answer 46

The Lysogenic Cycle

Question 47

In the lysogenic cycle, the integrated phage genome is called a ...

Answer 47

prophage

Question 48

What is a bacterial host with a prophage called?

Answer 48

lysogen

Question 49

The process by which a bacterium is infected by a temperate phage is called ...

Answer 49

lysogeny

Question 50

As a lysogen replicates its chromosome, the prophage is also replicated and passed on to new daughter cells during reproduction, altering their phenotype. This change in the host phenotype is called ...

Answer 50

lysogenic conversion or phage conversion

Question 51

What process results in the excision of the viral genome from the host chromosome, after which the temperate phage can proceed through a lytic cycle and then undergo lysogeny in a newly infected cell?

Answer 51

Induction

Question 52

This occurs when a bacteriophage transfers bacterial DNA from one bacterium to another during sequential infections.

Answer 52

Transduction

Question 53

What are the two types of Transduction?

Answer 53

Generalized transduction & Specialized transduction

Question 54

This type of transduction occurs when a random piece of bacterial chromosomal DNA is transferred by the phage (transducing phage) during the lytic cycle.

Answer 54

Generalized transduction

Question 55

A transduced bacterial cell or the cell that integrates a bacterial DNA transferred by a transducing phage from another bacterium to its chromosome is also called ...

Answer 55

Transductant

Question 56

Enumerate the stages of the Lytic Cycle in chronological order.

Answer 56

Attachment, Penetration, Biosynthesis, Maturation, & Lysis (Release)

Question 57

This type of transduction occurs at the end of the lysogenic cycle, when the prophage is excised and the bacteriophage enters the lytic.

Answer 57

Specialized transduction

Question 58

Enumerate the stages of the Specialized transduction in chronological order.

Answer 58

Viral attachment & penetration, Integration, Excision, Infection, & Recombination

Question 59

Many viruses are host-specific, meaning they only infect a certain type of host; and most viruses only infect certain types of cells within tissues. This phenomenon is known as ...

Answer 59

Tissue Tropism

Question 60

Which tissues does Poliovirus exhibit tropism?

Answer 60

tissues of the brain and spinal cord

Question 61

Which tissue does influenza virus has a primary tropism for?

Answer 61

respiratory tract tissues