Happy Wednesday, BIO-NINJAS
What you need: Writing Utensil, Bellwork Sheet, Journal
and virus worksheets.
Have Homework out. (Journals and worksheet)
Bellwork Today: Draw and Label the viruses
On your Vocab sheet: Highlight or mark these
words then glue into your journal
HOST CELL
GENETIC MATERIAL
VIRUSES
RETROVIRUS
IMMUNIZATION
LYTIC
LYSOGENIC
HIV
BACTERIOPHAGE
CAPSID
PATHOGEN
PARASITE
Vocab Quiz tomorrow over these words
You have 4 minutes to glue in your: Lysogenic
Sheet and Lytic sheet.
4 minutes
Set up today’s page in your journal…
• Date: 2-3-15
• Title: Viral Reproduction
• Essential Question: What takes place
when a virus reproduces?
YES - Cornell notes, please!
•
•
•
•
•
BIO.4C
The student will:
compare the structures of viruses to cells,
describe viral reproduction
describe the role of viruses in causing diseases
such as human immunodeficiency virus (HIV)
and influenza.
When a virus invades…
Viruses have both living and nonliving
characteristics.
Living
Non-Living
Reproduce Quickly
Need a host cell to function
They have DNA/RNA
Not made of cells
They can Mutate
Do Not Grow/Develop
Do not Metabolize/use energy
Do not react to the
environment
1. Lysogenic Cycle
Take a look at your “Lysogenic” sheet.
• Without me telling you anything, what do you
think is happening in the diagram?
*remember what you learned yesterday about
virus structure 
1. Lysogenic Cycle
• Viruses “hide” for a while inside host cells before becoming
active
• Example = HIV
1.
2.
3.
4.
5.
6.
Steps to the Lysogenic Cycle:
Virus attaches to cell
Virus injects DNA/RNA
Virus DNA/RNA Integrates and Waits (months or years) in
cell DNA
Virus DNA removes from cell DNA
Becomes active (starts lytic cycle)
Cell undergoes “lysis” (bursts)
- Viruses
Lysogenic Cycle
Ways to remember…
• Lysogenic is a Looooooong word
• LYS-ogenic---> sounds like “lies”
around or “lays low”
Lysogenic Example: HIV
• Enveloped virus
• Retroviruses transcribe RNA to DNA.
• Two viral strands of RNA found in core surrounded by
protein capsid.
AIDS
• White blood count drops below 200
person is considered to have advanced
HIV disease
• Most deaths occur with a white blood
count less than 50
• AZT = medicine used to treat HIV/AIDS
– Blocks “reverse trascriptase”
Lytic Cycle
Take a look at your “Lytic” sheet.
• Without me telling you anything, what do you
think is happening in the diagram?
*remember what you just learned about virus
replication 
Lytic Cycle
•Lysis- to cut or to burst
•Active viruses enter cells and immediately begin to
multiply, leading to the quick death of the invaded cells.
Steps to the lytic cycle:
1. Attach to cell
2. Inject DNA/RNA
3. Produce (replicate) virus parts
4. Assemble new virons
5. Cell undergoes “Lysis”- viruses are released to
infect other cells
- Viruses
Lytic Cycle
Ways to remember
• Lytic = the shorter word, therefore shorter cycle
• Lytic = Bang Bang (kill you dead)
• Lytic  sounds like you got “lit up”
Lytic Example: Influenza
• Enveloped virus with a
segmented RNA
• Symptoms appear
within days/weeks
• Infects a wide range of
animals other than
humans
• Undergoes extensive
mutations
• Causes the flu
Spread of influenza virus
Today’s Activity:
Sage and Scribe
Happy Friday
Comic Strip
Lytic or Lysogenic?
DISEASE
VIRUSES
AIDS
HIV
Wart
Herpes Simplex
Virus
Flu
Measles
Cancer
Influenza
Morbillivirus
Hepatitis B
Dengue Fever
.