1. Virus
Chapter 2 Lesson 1

2. What are the characteristics of Viruses?
Non-living
Tiny
Genetic material protected by a protein coat
Unable to reproduce on their own

3. Why are viruses considered nonliving?
Lack characteristics of living things:
are not cells
don’t use their own energy to grow or respond to surroundings
cannot make food, take in food or produce wastes
cannot reproduce on their own

4. Viral shapes Bacteriophages Spherical (RNA) Crystal (stable. Polio)
Cylinder (plant)

5. Virus Structure
Two parts: core of genetic material & a protein coat with surface proteins
The virus surface proteins, like keys, only fit into certain host cells
Ex. HIV infects the cells of the immune system

6. Viruses & the World Can cause disease Useful
Once recovered from a viral illness the body becomes immune
Useful
Vaccines, built from viruses, are used to cause immunity in organisms so they cannot be made ill from a virus
Gene therapy uses the viral mechanism for infection to deliver new genetic material to cells that need it