OCCC Microbiology Unit 6 Powerpoint and Objectives
UPDATED ACTUAL Questions and CORRECT Answers
No universal agreement on how and when viruses
originated
Viruses are considered most abundant microbes on
earth
Viruses played role in evolution of Bacteria, Archaea,
and Eukarya
Viruses are obligate intracellular parasites
, ACTIVITY: Create a Venn diagram of the properties of Bacteria/cells:
viruses and cells (This will help you think about how - living organism
viruses and cells are different and similar). - unicellular
- microscopic
- reproduces by fission
- usually treated with antibiotics
Viruses:
- non living
- noncellular
- ultramicroscopic
- reproduce by taking over the host cell
- antiobiotics don't have an effect
- bear no resemblance to cells/only contain parts needed to invade host cell
Both:
- Cause disease
- Similar modes of transmission
- Possibility to be vaccinated
- Can be fatal
Viral components of a virus
- Capsids
- Nucleic acids
- Envelopes
Viruses bear no resemblance to cells (they lack
protein-synthesizing machinery)
Viruses contain only parts needed to invade and
control host cell
GENERAL STRUCTURE OF VIRUSES: CAPSID
All viruses have capsids
*capsid* Protein coat surrounding a virus (enclose and protect their nucleic acid)
*Nucleocapsid* capsid together with a nucleic acid
Some viruses have an external covering called
*envelope; those lacking an envelope are naked*
Each capsid is constructed from identical subunits
called *capsomers* made of protein
GENERAL STRUCTURE OF VIRUSES: SHAPE
Two structural types for a virus:
1. helical
2. Icosahedral
UPDATED ACTUAL Questions and CORRECT Answers
No universal agreement on how and when viruses
originated
Viruses are considered most abundant microbes on
earth
Viruses played role in evolution of Bacteria, Archaea,
and Eukarya
Viruses are obligate intracellular parasites
, ACTIVITY: Create a Venn diagram of the properties of Bacteria/cells:
viruses and cells (This will help you think about how - living organism
viruses and cells are different and similar). - unicellular
- microscopic
- reproduces by fission
- usually treated with antibiotics
Viruses:
- non living
- noncellular
- ultramicroscopic
- reproduce by taking over the host cell
- antiobiotics don't have an effect
- bear no resemblance to cells/only contain parts needed to invade host cell
Both:
- Cause disease
- Similar modes of transmission
- Possibility to be vaccinated
- Can be fatal
Viral components of a virus
- Capsids
- Nucleic acids
- Envelopes
Viruses bear no resemblance to cells (they lack
protein-synthesizing machinery)
Viruses contain only parts needed to invade and
control host cell
GENERAL STRUCTURE OF VIRUSES: CAPSID
All viruses have capsids
*capsid* Protein coat surrounding a virus (enclose and protect their nucleic acid)
*Nucleocapsid* capsid together with a nucleic acid
Some viruses have an external covering called
*envelope; those lacking an envelope are naked*
Each capsid is constructed from identical subunits
called *capsomers* made of protein
GENERAL STRUCTURE OF VIRUSES: SHAPE
Two structural types for a virus:
1. helical
2. Icosahedral
