BIOD 171 MODULE 6 ESSENTIAL MICROBIOLOGY EXAM PREP QUESTIONS ANSWERS BUNDLED SOLUTIONS HIGH QUALITY PRACTICE MATERIAL

BIOD 171 MODULE 6 ESSENTIAL
MICROBIOLOGY EXAM PREP QUESTIONS
ANSWERS BUNDLED SOLUTIONS HIGH
QUALITY PRACTICE MATERIAL

●● virus composition
Answer: 2 basic components:
- genomic material (DNA or RNA)
- capsid


●● capsid
Answer: membrane-like protective structure that contains genetic
material (similar to nucleus)


- most viruses have icosahedral/ helical structure
- fewer viruses have complex structure


●● viral genome
Answer: small, can be either double or single-stranded


- may be circular or linear
- size varies from few thousand to 2.5 million nucleotide base pairs

,●● DNA viral genome
Answer: - circular or linear
- often double stranded


●● RNA viral genome
Answer: - linear or segmented
- often single stranded


●● virion size
Answer: smaller than a cell


●● envelope
Answer: additional membrane to external env. surrounding capsid,
derived from host cell membrane


eg. most animal viruses


●● naked (non-enveloped)
Answer: a virus simply surrounded by protein capsid and no envelope


eg. most plant/bacteria-infecting viruses

, ●● paramyxoviruses
Answer: causative agent of measles & mumps, contain single-stranded
linear genome & fuse w/ host cell membrane to initiate entry & viral
replication


- enveloped, spherical, ~100-150 nm


●● orthomyxoviruses
Answer: causative agent of flu, contain 8 segments of RNA & enter host
cell via endocytosis


- enveloped, spherical, ~100-150 nm


●● factors grouping viral families
Answer: - DNA or RNA genome
- capsid shape (icosahedral, helical, complex)
- enveloped or naked
- structure of genome (circular, linear, segmented)
- in RNA: presence or absence of reverse transcriptase


●● microscopy to view virus
Answer: electron microscopy