Biology - Viruses

Virus Structure

• protein coat (capsid)

• nucleic acid (RNA or DNA)

LIving Features of Viruses

• contain genetic material (DNA or RNA)

• have a protein coat

• can replicate inside a living cell

Non Living Features of Viruses

• non-cellular

• cannot reproduce by themselves

• do not have ribosomes, mitochondria, or other cell organelles

• only have one type of nucleic acid

Virus Shapes

• round

• rod-shaped

• complex

Obligate Parasites

viruses cannot replicate by themselves (they must multiply using the energy and structures of a live host cell)

Bacteriophage

a virus that infects bacteria

Viral Replication

1. Attachment

2. Entry (nucleic acid pushed through)

3. Synthesis

4. Assembly

5. Release

Disadvantages of Viruses

1. human diseases

2. plant diseases

3. animal diseases

Benefits of Viruses

• transfer genes from one organism to another

• control bacterial infections

Antibiotics

do not affect viruses