Download Virus Structure

Virus Structure
Bellwork
CO: I will compare and describe the
structure of a virus to a cell.
LO: I will read and watch a video
about viruses. I will build a virus.
Science Fact of the Day:
Some migratory birds have a "magnetic compass" in
their body (a sense called Magnetoreception) to help
them navigate using Earth's magnetic field.
Viruses
Anticipation Guide:
Discuss the following statements with
a partner. Determine if you think they
are true or false.
1.
2.
3.
4.
5.
Viruses affect us just like bacteria.
Viruses have DNA.
Viruses can be cured by antibiotics.
Viruses are not alive.
Being a zombie is caused by a virus.
OVERVIEW
Generalized Structure of Viruses
Viral components
– Nucleic acids
• DNA or RNA
– Capsid
• Protein
– Envelope
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Generalized Structure of Viruses
Generalized Structure of Viruses
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Viruses are highly specific to the cells they infect
Examples: 1) plant viruses infect plant cells
2) animal viruses infect only certain
related species of animals
3) bacterial viruses (bacteriophage)
infect only certain types of bacteria.
So, what about
zombies?
Think-Pair-Share
Are viruses alive?
(Justify your answer)
Viruses have both living and nonliving
characteristics.
Living characteristics of viruses:
• They reproduce at a fantastic rate, but only
in living host cells.
• They can mutate.
• They contain DNA or RNA
Nonliving characteristics of viruses:
• They are acellular, they contain no cytoplasm
or cellular organelles. They are not made of
cells.
• They carry out no metabolism on their own
and must replicate using the host cell's
metabolic machinery.
• They do not grow or develop
Viruses are NOT alive because
they DO NOT have ALL of the
characteristics of life.
Viruses range in size from 20 nanometers (nm) – 250 nanometers (nm)
1 nm = 0.00000004 inches
atom
proteins
If a cell was the size of your classroom, then an average virus
would be the size of a softball.
viruses
animal
cells
bacteria
0m
10-6 m
10-5 m
10-7 m
10-8 m
10-9 m
Go five more feet!
10-10 m
A virus’ size helps it to reproduce. We’ll talk about
this tomorrow.
Virus Structure
Cell Structure
Virus Structure Activity
• Create a model of a virus as instructed by your
teacher
• Label the model correctly
• Summarize in 14 words how the structure of
your virus is different than a cell.