Download PowerPoint Presentation - Ch. 10 Molecular Biology of the Gene

Ch. 10
Molecular Biology of the Gene
10.17 – 10.22
• What are two ways in
which bacteriophage can
reproduce?
• Lytic cycle: Lysis or
breaking open of the cell
• Lysogenic cycle: inserts
its DNA into a
chromosome of the host
cell, which will replicate
both the virus and its own
DNA.
• An influenza virus, aka: “the
flu” has RNA rather than DNA.
• What is the purpose of RNA?
• Serves as template for making
more viral-genome RNA &
mRNA for synthesis of new
viral-proteins
• What is the purpose of the
glycoprotein spikes?
• Helps virus enter and leave
cells
• Other RNA viruses include the
common cold, measles &
mumps.
• DNA viruses include hepatitis,
chicken pox & herpes.
• How does a virus
reproduce without having
DNA polymerase or
ligase?
• Virus uses that infected
cells organelles to
reproduce (HIJACK)
• RNA is replicated inside
the host cell by special
enzymes encoded by the
virus.
• Viral RNA serves as
mRNA for synthesis of
viral proteins.
• In what ways do Viruses
enter humans?
• Lesions or bodily fluids,
insects, contaminated
foods & surfaces
• How do they get into
plant cells?
• Lesions caused by injury
• Transfered from insects
feeding on them
• Contaminated farming or
gardening tools
• Mutations of existing
viruses is a major source
of new viral diseases.
Why is this dangerous?
• Cause disease in people
with immunity to the old
virus.
• Come from animals (Give
example…chirp chirp)
• Start isolated and spread
suddenly (AIDS)
• HIV has some special
twists to it such as?
• Membrane envelope like
mumps to leave the cell
(disguised)
• 2 strands of RNA
• HIV is a retrovirus…what
is that?
• Retrovirus – reverse
transcription because of
reverse transcriptase
(RNA to DNA)
• How can a retrovirus make
DNA from RNA?
• Uses RNA as template to
synthesize DNA from its RNA
genome, sends DNA into cell
nucleus
• What’s a provirus?
• Foreign DNA inserted into your
DNA…
• Can be transcribed, translated
to viral proteins. New viruses
are made & leave cell to infect
and reproduce in other cells.
• What do you think are
all the blue dots on
the red blob?
• HIV attacking the
white blood cells
killing them, and
weakening your
immune system.