GMS 6121 Exam 1 Module 1.1 Test
Questions and All Correct Answers.
How many cell types and organ systems do viruses target? - Answer All of them
Do individual viruses exhibit tropism? - Answer Yes, they favor particular cell types and organs
What type of parasites are viruses? - Answer Obligate intracellular
What do viruses lack that they must gain from their host? - Answer 1. enzymes that produce
basic chemical building blocks
2. enzymes that generate usable energy
3. enzymes, tRNAs, and/or ribosomes that direct protein synthesis
4. membranes that concentrate and localize key molecules
What do ALL viruses have? - Answer nucleic acid
capsid - protein coat encoded by the virus
What do SOME viruses have? - Answer envelope - lipid membrane provided by the host
What is a virion? - Answer a complete, infectious virus particle
How do viruses compare to bacteria? - Answer MUCH smaller
first discovered because of their size, used a filter to screen out bacteria and found pathogenic
particles still present = virus
What is the basic virus structure? - Answer DNA or RNA + Capsid protein = nucleocapsid
Nucleocapsid = naked capsid virus
, Enveloped virus = sensitive to drying, heat, detergents, acid
What are the pros and cons of naked capsid virus? - Answer -retain infectivity on drying
-survive well on environmental surfaces
-spread easily via fomites
-can survive acidic environment of GI tract
-MUST kill host cells to release mature virus particles
-Antibody response may be sufficient to neutralize infection
What are the pros and cons of enveloped virus? - Answer -does not need to kill cells in order
to spread
- may require both humoral and cellular immune responses
-can not survive GI tract
-must stay wet during transmission
-transmission in large droplets and secretions
Capsids are usually: - Answer simple = 1-3 proteins
symmetrical
What are the two configurations of capsids? - Answer icosahedral
helical
for both enveloped and naked
What is the configuration of a helical naked capsid virus? - Answer nucleic acid spiraled in the
center
proteins wrap around outside
ex. tobacco mosaic virus
Questions and All Correct Answers.
How many cell types and organ systems do viruses target? - Answer All of them
Do individual viruses exhibit tropism? - Answer Yes, they favor particular cell types and organs
What type of parasites are viruses? - Answer Obligate intracellular
What do viruses lack that they must gain from their host? - Answer 1. enzymes that produce
basic chemical building blocks
2. enzymes that generate usable energy
3. enzymes, tRNAs, and/or ribosomes that direct protein synthesis
4. membranes that concentrate and localize key molecules
What do ALL viruses have? - Answer nucleic acid
capsid - protein coat encoded by the virus
What do SOME viruses have? - Answer envelope - lipid membrane provided by the host
What is a virion? - Answer a complete, infectious virus particle
How do viruses compare to bacteria? - Answer MUCH smaller
first discovered because of their size, used a filter to screen out bacteria and found pathogenic
particles still present = virus
What is the basic virus structure? - Answer DNA or RNA + Capsid protein = nucleocapsid
Nucleocapsid = naked capsid virus
, Enveloped virus = sensitive to drying, heat, detergents, acid
What are the pros and cons of naked capsid virus? - Answer -retain infectivity on drying
-survive well on environmental surfaces
-spread easily via fomites
-can survive acidic environment of GI tract
-MUST kill host cells to release mature virus particles
-Antibody response may be sufficient to neutralize infection
What are the pros and cons of enveloped virus? - Answer -does not need to kill cells in order
to spread
- may require both humoral and cellular immune responses
-can not survive GI tract
-must stay wet during transmission
-transmission in large droplets and secretions
Capsids are usually: - Answer simple = 1-3 proteins
symmetrical
What are the two configurations of capsids? - Answer icosahedral
helical
for both enveloped and naked
What is the configuration of a helical naked capsid virus? - Answer nucleic acid spiraled in the
center
proteins wrap around outside
ex. tobacco mosaic virus
