1. Bacteria & Viruses
Unit 6 – Lecture 1

2. Note:
Read and LISTEN!!
I mentioned this at the beginning of the year and semester , but as the year progresses, you’ll have less and less notes given on the screen…
in this unit, you’ll have both information on the screen itself, AND info that you’ll need to listen for [not everything will be on the board]
so Read and LISTEN!!

3. Recall Classification
Organisms are classified by:
cell type
body type
how they attain nutrition
genetic composition

4. Domains
There are three domains of Life:
Bacteria
Archaea
Eukarya

5. Domain: Bacteria
Kingdom Eubacteria
prokaryotic
unicellular

6. Domain: Bacteria Kingdom Eubacteria asexual reproduction
sometimes with conjugation using pili [sing = pilus]

7. Domain: Bacteria Kingdom Eubacteria strong cell wall
can be autotroph or heterotroph
saphrophyte
parasite
chemoautotroph
photoautotroph

8. Domain: Bacteria Kingdom Eubacteria
found almost everywhere except for extreme environments
some have locomotion
flagella
cilia

9. Domain: Bacteria Kingdom Eubacteria three basic body shapes: bacillus
coccus
spirillum
strep = chains
staph = clusters

11. Discuss
Summarize the characteristics of Eubacteria and check over your notes with a partner to make sure you got everything.

12. Domain: Archaea Kingdom Archaebacteria prokaryotic unicellular
asexual reproduction
sometimes with conjugation

13. Domain: Archaea Kingdom Archaebacteria
strong cell wall with unique composition
autotrophic
photoautotroph
chemoautotroph

14. Domain: Archaea Kingdom Archaebacteria
closer genetically to eukaryotes than eubacteria
live in extreme environments
high heat, high salt

15. Discuss
Summarize the characteristics of Archaebacteria and check over your notes with a partner to make sure you got everything.

16. Domain: Eukarya Kingdoms Protista, Fungi, Animalia, Plantae
very diverse but all are eukaryotic
unicellular or multicellular
highly organized
sexual or asexual reproduction

17. Recall – Characteristics of Life
It is debatable if viruses are truly alive or not.
Discuss with a partner whether or not you think a virus fulfills the characteristics which all living things must have.
organized (into cells)
reproduces
can pass traits to offspring
grows/develops
needs energy
maintains homeostasis
responds to stimuli ?

18. Viruses
Multiple forms:
helix
icosahedral
bacteriophage
and more

19. Viruses Nucleic Acid Bacteriophage anatomy
[aka T-4 bacteriophage or just “phage”]
head = capsid
sheath aka tail
Nucleic Acid

20. Viruses Reproduction must occur in a host cell two cycles: lytic cycle
lysogenic cycle

21. Viruses Lytic Cycle attachment infection incorporation of nucleic acid
replication: viral DNA uses host to replicate DNA and make more viruses
destruction of cell

22. Viruses Lysogenic Cycle attachment infection
incorporation of nucleic acid
DNA is dormant & replicates with cell info during cell cycle

23. Viruses Prion – “evil misshapen protein” / viral protein
responsible for mad cow disease which destroys brain tissue
recent discoveries, however, show that “normal” prions may have an important role in keeping nerve cells healthy

24. Viruses
Uses for viruses
vaccines
gene therapy
Cystic Fibrosis

25. Recall – Characteristics of Life
So…are viruses alive? Why or Why Not? Which characteristics does it share with living things?
organized (into cells)
reproduces
can pass traits to offspring
grows/develops
needs energy
maintains homeostasis
responds to stimuli ?

26. Homework Complete the worksheet on the backside of your lecture notes
Draw, Label & Color Bacteria & Viruses