What is a virus?
Particles of nucleic acid, protein and sometimes lipids that can reproduce
only by infecting other cells
What is the structure of a virus?
Composed of a core of either DNA or RNA surrounded by a protein coat.
How much genetic material does a virus have?
Simple viruses have a few genes, more complex viruses can have more than
one hundred genes
What parts do all types of viruses have in common?
A capsid, and a core of nucleic acid, either DNA or RNA
What is a capsid and what does it do?
A capsid is a virus’s outer protein coat. The proteins in the capsid “trick” a
cell into allowing the virus inside.
What are some diseases caused by viruses?
Polio, measles, mumps, influenza, yellow fever, rabies and the common cold.
How can someone protect themselves against a viral disease?
A vaccine is a preparation of weakened or killed virus which when injected
into the body stimulates the immune system to fight against the virus
immediately.
Viruses that contain RNA copy their genetic information backwards,
from RNA to DNA. What are these viruses called?
Retroviruses, like HIV, do not contain DNA
What are protein particles that can cause disease called?
Prions, which is short for protein infectious particles, may be the cause of
Mad Cow disease
LYTIC INFECTION
Virus enters cells, makes copies of itself and causes the cell to burst.
LYSOGENIC INFECTION
Virus embeds its DNA into host’s DNA and is replicated along with host’s DNA.
This can go on indefinitely.
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#1:
The results support the idea that DNA is the genetic material. Most of the
viral DNA entered the host, while most of the protein remained outside the cell.
The radioactive DNA was replicated in the cell.
#2:
If both proteins and DNA had entered the cell, this would not have
provided a possible explanation to the question.