MICROBIOLOGY A SYSTEMS APPROACH
EXAM PREP 2026 SOLVED QUESTIONS
ANSWERS GRADED A PLUS LAB
DIAGNOSTICS HANDBOOK
◉ Ivanovski and Beijernick
Answer: discovered that tobacco disease caused by virus
◉ Loeffler and Frosch
Answer: discovered foot-and-mouth disease caused by virus
◉ filterable virus
Answer: infectious fluids were passed through filters designed to
trap bacteria.
the cell-free fluid remained infectious
= proved that an agent smaller than bacteria was the cause of
disease
◉ True/False: Viruses can be cultured using the same methods as
bacteria and fungi.
Answer: False; need living host such as chick embryo
,◉ Pasteur developed a vaccine for the _______ virus
Answer: Rabies
◉ Viruses were discovered by filtering infectious fluid through a
filter designed to trap ________.
Answer: bacteria
◉ Unique properties of viruses
Answer: Infectious particles; rather than organisms
Active or inactive; rather than alive or dead
Obligate intracellular parasites:
-cannot multiply unless they invade a specific host cell
-must instruct the genetic and metabolic machinery of the host cell
to make and release new viruses
◉ True/False: Viruses are alive.
Answer: False
◉ What percentage of the bacterial chromosome is composed of
viral genes?
Answer: 10-20%
,◉ Discuss the predominant view among scientists as to the nature of
viruses.
Answer: infectious particle
◉ List and describe 5 unique properties of viruses.
Answer: not alive, do not reproduce on their own, very small, core
contains nucleic acids,
◉ virus size
Answer: ultra microscopic size
electron microscope required to see them
parvoviruses: 20 nm in diameter
mimiviruses: 450 nm in length - larger than some small bacteria
cylindrical viruses: 800 nm long, but 15 nm in diameter
◉ capsid
Answer: shell surrounds the nucleic acid
◉ nucleocapsid
Answer: capsid and nucleic acid together
, ◉ envelope
Answer: usually a modified piece of the host cell membrane
◉ naked virus
Answer: consists only of a nucleocapsid
◉ spikes
Answer: found on both naked and enveloped viruses
project from either the nucleocapsid or envelope
allow viruses to dock with their host cells
spikes: protruding glycoproteins essential for attachment to the host
cell
◉ virion
Answer: fully formed virus able to establish infection in a host
◉ capsomeres
Answer: - identical protein subunits that spontaneously self
assemble to form the capsid
EXAM PREP 2026 SOLVED QUESTIONS
ANSWERS GRADED A PLUS LAB
DIAGNOSTICS HANDBOOK
◉ Ivanovski and Beijernick
Answer: discovered that tobacco disease caused by virus
◉ Loeffler and Frosch
Answer: discovered foot-and-mouth disease caused by virus
◉ filterable virus
Answer: infectious fluids were passed through filters designed to
trap bacteria.
the cell-free fluid remained infectious
= proved that an agent smaller than bacteria was the cause of
disease
◉ True/False: Viruses can be cultured using the same methods as
bacteria and fungi.
Answer: False; need living host such as chick embryo
,◉ Pasteur developed a vaccine for the _______ virus
Answer: Rabies
◉ Viruses were discovered by filtering infectious fluid through a
filter designed to trap ________.
Answer: bacteria
◉ Unique properties of viruses
Answer: Infectious particles; rather than organisms
Active or inactive; rather than alive or dead
Obligate intracellular parasites:
-cannot multiply unless they invade a specific host cell
-must instruct the genetic and metabolic machinery of the host cell
to make and release new viruses
◉ True/False: Viruses are alive.
Answer: False
◉ What percentage of the bacterial chromosome is composed of
viral genes?
Answer: 10-20%
,◉ Discuss the predominant view among scientists as to the nature of
viruses.
Answer: infectious particle
◉ List and describe 5 unique properties of viruses.
Answer: not alive, do not reproduce on their own, very small, core
contains nucleic acids,
◉ virus size
Answer: ultra microscopic size
electron microscope required to see them
parvoviruses: 20 nm in diameter
mimiviruses: 450 nm in length - larger than some small bacteria
cylindrical viruses: 800 nm long, but 15 nm in diameter
◉ capsid
Answer: shell surrounds the nucleic acid
◉ nucleocapsid
Answer: capsid and nucleic acid together
, ◉ envelope
Answer: usually a modified piece of the host cell membrane
◉ naked virus
Answer: consists only of a nucleocapsid
◉ spikes
Answer: found on both naked and enveloped viruses
project from either the nucleocapsid or envelope
allow viruses to dock with their host cells
spikes: protruding glycoproteins essential for attachment to the host
cell
◉ virion
Answer: fully formed virus able to establish infection in a host
◉ capsomeres
Answer: - identical protein subunits that spontaneously self
assemble to form the capsid
