4,5,6) QUESTIONS WITH 100%
CORRECT ANSWERS 2026 VERIFIED
A+
◉ When are Viruses considered to be "alive"?
Answer: When they are inside of a host cell.
When inside, their nucleic acid (ONLY RNA OR DNA) become active.
*Virus replicates
◉ Obligatory Intracellular Parasites
Answer: Require livinghost cell in order to multiply - Such as Viruses.
◉ Defining a Virus
Answer: 1) Contains 1 Nucleic Acid (DNA or RNA)
2) Protein coat surrounds the DNA or RNA
3)Multiply within host using host machinery
---because they don't have the ways of making/obtaining their own
nutrients. like ATP or enzymes.
◉ Virus Characteristics
Answer: *Some are enclosed by an envelope which consists of lipids,
proteins, carbohydrates
,*some have spikes
*only infect the cells of ONE host.
◉ Host Range
Answer: The spectrum of host cells that a virus can infect.
-invertebrates
-vertebrates
-plants
-protist
-fungi
-bacteria
The virus must be able to attach to a the particular host's cell.
**Host range is determined b specific attachment sites on the host cell's
surface
◉ Bacteriophages
Answer: Bacteria that is infected by a virus
◉ How do Viruses attach to a host cell
,Answer: Through receptors on the host cell's surface.
There must be an interaction.
◉ Capsid
Answer: Protein coat that surrounds the Nucleic Acid of a virus. (not the
whole virus itself. That's an envelope.)
****Made up of individualized Capsomeres****
*accounts for most of the mass of a viral cell.
◉ Capsomeres
Answer: Protein subunits that make up a capsid
(think of tiny balls that come together to make a huge coating around the
Nucleic Acid)
*capsomeres can be made up of multiple types of proteins or one single
type of protein
◉ Envelope
Answer: Surrounds the virus as a whole.
*Synonymus to a somatic cell's Plasma Membrane. But around a virus.
, ***Composed of proteins, lipids and carbs.
*Could be covered in spikes
NOT ALL VIRUSES HAVE ENVELOPES
◉ Spikes
Answer: Cover the envelope of the cell
Composed of protein and carbohydrates.
-Used for attachment to the host cell
Spikes differ, and can be identified as different virus by the host body.
That's why you can get the flu more than once a year, there's a change in
spikes.
-Can be used for identification for some virsus under microscope.
◉ Helical Capsid
Answer: Long rods that are flexible and rigid
These surround the Nucleic Acid.
*Capsids are hollow cylinders surrounding the nucleic acid.