Acellular Microbes (Viruses)

Question 1

What is the basic structural unit of a virus?

Answer 1

A virus is made up of a nucleic acid core (either DNA or RNA) surrounded by a protein coat called a capsid.

Question 2

True or False: Viruses have a cellular structure.

Answer 2

False: Viruses do not have a cellular structure.

Question 3

What is the function of the viral capsid?

Answer 3

The viral capsid protects the viral nucleic acid and aids in the delivery of the viral genome into host cells.

Question 4

Fill in the blank: The envelope of a virus is derived from the __________ of the host cell.

Answer 4

membrane

Question 5

What are the two main types of viral nucleic acids?

Answer 5

DNA and RNA.

Question 6

What is a viral envelope?

Answer 6

A viral envelope is a lipid bilayer that surrounds some viruses, derived from the host cell’s membrane.

Question 7

True or False: All viruses have an envelope.

Answer 7

False: Not all viruses have an envelope; those without are called naked viruses.

Question 8

What role do viral proteins play in the virus structure?

Answer 8

Viral proteins are involved in the virus’s attachment to host cells and can also have enzymatic functions.

Question 9

What is the term for the specific shape of a virus determined by its capsid?

Answer 9

The shape of a virus is referred to as its morphology, which can be helical, icosahedral, or complex.

Question 10

Multiple Choice: Which of the following is NOT a type of viral morphology? A) Helical B) Icosahedral C) Quadrilateral D) Complex

Answer 10

C) Quadrilateral

Question 11

What is the significance of viral glycoproteins?

Answer 11

Viral glycoproteins are crucial for the virus’s ability to attach to and enter host cells.

Question 12

True or False: Viruses can replicate independently of host cells.

Answer 12

False: Viruses cannot replicate independently; they require a host cell.

Question 13

What is the term for the protein subunits that make up the capsid?

Answer 13

Capsomers.

Question 14

What is a bacteriophage?

Answer 14

A bacteriophage is a type of virus that specifically infects bacteria.

Question 15

Fill in the blank: The genetic material of a virus can be __________ or __________.

Answer 15

single-stranded or double-stranded

Question 16

What is the primary function of the viral genome?

Answer 16

The viral genome carries the information necessary for the virus to replicate and produce new viral particles.

Question 17

Multiple Choice: Which structure helps a virus to evade the host immune response? A) Capsid B) Envelope C) Nucleic acid D) All of the above

Answer 17

B) Envelope

Question 18

What is the role of the viral matrix proteins?

Answer 18

Matrix proteins provide structural support and play a role in the assembly of the virus.

Question 19

True or False: Viruses can contain both DNA and RNA in their structure.

Answer 19

False: Viruses contain either DNA or RNA, not both.

Question 20

What are non-structural proteins in a virus?

Answer 20

Non-structural proteins are proteins that are not part of the virus’s structure but are involved in the virus’s life cycle, such as replication and assembly.

Question 21

Fill in the blank: The __________ is the outermost layer of a virus that may help it enter host cells.

Answer 21

envelope

Question 22

What is the role of the viral core?

Answer 22

The viral core contains the nucleic acid and associated proteins essential for viral replication.

Question 23

Multiple Choice: Which type of virus has a helical structure? A) Influenza B) HIV C) Adenovirus D) Polio

Answer 23

A) Influenza

Question 24

What is the importance of the viral life cycle for understanding virus structure?

Answer 24

Understanding the viral life cycle helps in identifying structural components that are critical for infection and replication.

Question 25

What is a virus?

Answer 25

A virus is a microscopic infectious agent that can only replicate inside the living cells of an organism.

Question 26

True or False: Viruses are considered living organisms.

Answer 26

False

Question 27

Fill in the blank: Viruses consist of genetic material surrounded by a ______.

Answer 27

protein coat

Question 28

What are the two main types of viral genetic material?

Answer 28

DNA and RNA

Question 29

Multiple Choice: Which of the following is NOT a characteristic of viruses? A) They can reproduce on their own B) They contain genetic material C) They can infect living cells D) They are smaller than bacteria

Answer 29

A) They can reproduce on their own

Question 30

What is the term for the protein coat surrounding a virus?

Answer 30

Capsid

Question 31

True or False: Viruses can infect all forms of life.

Answer 31

True

Question 32

What is a viral envelope?

Answer 32

A viral envelope is a lipid membrane that surrounds some viruses, derived from the host cell membrane.

Question 33

Fill in the blank: Viruses can be classified based on their ______ type.

Answer 33

nucleic acid

Question 34

Short Answer: Name one method viruses use to enter host cells.

Answer 34

Endocytosis

Question 35

Multiple Choice: Which of the following is a characteristic of RNA viruses? A) They have double-stranded DNA B) They can mutate rapidly C) They are always enveloped D) They are larger than DNA viruses

Answer 35

B) They can mutate rapidly

Question 36

What is the role of viral receptors?

Answer 36

Viral receptors are proteins on the surface of host cells that viruses use to attach and enter the cells.

Question 37

True or False: All viruses have an outer envelope.

Answer 37

False

Question 38

What is a bacteriophage?

Answer 38

A bacteriophage is a type of virus that specifically infects bacteria.

Question 39

Fill in the blank: Viruses that only infect eukaryotic cells are called ______ viruses.

Answer 39

eukaryotic

Question 40

Short Answer: Describe how viruses replicate inside host cells.

Answer 40

Viruses hijack the host's cellular machinery to replicate their genetic material and produce new virus particles.

Question 41

Multiple Choice: Which of the following best describes the lytic cycle? A) The virus integrates its DNA into the host genome B) The virus causes the host cell to burst C) The virus remains dormant in the host D) The virus only infects plants

Answer 41

B) The virus causes the host cell to burst

Question 42

What is the difference between the lytic and lysogenic cycles?

Answer 42

The lytic cycle results in the destruction of the host cell, while the lysogenic cycle involves the integration of viral DNA into the host genome without immediate destruction.

Question 43

True or False: Viruses can evolve over time.

Answer 43

True

Question 44

Fill in the blank: The study of viruses is known as ______.

Answer 44

virology

Question 45

Short Answer: What is a viral mutation?

Answer 45

A viral mutation is a change in the viral genome that can affect the virus's properties, such as its ability to infect host cells.

Question 46

Multiple Choice: What is one way viruses can be transmitted from one host to another? A) Photosynthesis B) Direct contact C) Cellular respiration D) Fermentation

Answer 46

B) Direct contact

Question 47

What are antiviral drugs?

Answer 47

Antiviral drugs are medications used to treat viral infections by inhibiting the development of the virus.

Question 48

True or False: Vaccines can provide immunity against viruses.

Answer 48

True

Question 49

Fill in the blank: The process by which a virus is released from a host cell is called ______.

Answer 49

budding

Question 50

What are the main stages of the viral growth cycle?

Answer 50

The main stages are attachment, penetration, uncoating, replication, assembly, and release.

Question 51

True or False: Viruses can replicate independently without a host cell.

Answer 51

False

Question 52

Fill in the blank: The process by which a virus attaches to a host cell is called __________.

Answer 52

attachment

Question 53

What happens during the uncoating stage of the viral growth cycle?

Answer 53

The viral capsid is removed, releasing the viral genome into the host cell.

Question 54

Multiple Choice: Which step follows the penetration of the virus into the host cell? A) Assembly B) Uncoating C) Attachment D) Release

Answer 54

B) Uncoating

Question 55

What is the role of viral RNA or DNA during replication?

Answer 55

It serves as a template for synthesizing new viral proteins and genomes.

Question 56

True or False: The assembly stage involves the formation of new virions from replicated components.

Answer 56

True

Question 57

What is the significance of the release stage in the viral growth cycle?

Answer 57

It allows new virions to exit the host cell and infect other cells.

Question 58

Fill in the blank: The lifecycle of a virus is often referred to as the __________ cycle.

Answer 58

viral growth

Question 59

What is a virion?

Answer 59

A complete virus particle that consists of nucleic acid surrounded by a protein coat.

Question 60

Multiple Choice: Which of the following is NOT a method of viral release? A) Lysis B) Budding C) Binary fission D) Exocytosis

Answer 60

C) Binary fission

Question 61

Describe the role of host cell machinery in viral replication.

Answer 61

Host cell machinery is hijacked by the virus to produce viral components necessary for replication.

Question 62

True or False: Viruses can infect any type of cell.

Answer 62

False

Question 63

What determines the specificity of a virus for its host?

Answer 63

The presence of specific receptors on the host cell surface that the virus can bind to.

Question 64

Fill in the blank: The viral genome can be either __________ or __________.

Answer 64

RNA, DNA

Question 65

What is the difference between lytic and lysogenic cycles?

Answer 65

In the lytic cycle, the virus destroys the host cell, while in the lysogenic cycle, the viral genome integrates into the host genome and can remain dormant.

Question 66

Multiple Choice: Which stage is critical for the production of new viral particles? A) Attachment B) Penetration C) Replication D) Release

Answer 66

C) Replication

Question 67

What is the primary outcome of the viral growth cycle?

Answer 67

The production of new virions that can go on to infect additional host cells.

Question 68

True or False: All viruses have an envelope.

Answer 68

False

Question 69

What is the function of a viral envelope?

Answer 69

It helps the virus enter host cells and evade the host immune response.

Question 70

Fill in the blank: The __________ phase of viral growth is when the virus is actively replicating.

Answer 70

exponential

Question 71

What does the term 'viral load' refer to?

Answer 71

The amount of viral particles present in a given volume of fluid.

Question 72

Multiple Choice: Which of the following is a common method for studying viral replication? A) PCR B) Western blot C) Microscopy D) All of the above

Answer 72

D) All of the above

Question 73

What is a common outcome of the lytic cycle?

Answer 73

Cell lysis and the release of new virions.

Question 74

True or False: Viruses can evolve over time.

Answer 74

True