Prokaryotes like archaebacteria and eubacteria are Earth's most abundant life forms. They are capable of living in many environments and obtaining energy from different sources. Bacteria are mostly single-celled organisms that lack nuclei and organelles, have circular chromosomes, and reproduce asexually or through conjugation. Viruses are not considered living as they require a host cell to reproduce, but they do evolve and regulate gene expression like other organisms. They enter host cells and use the cell's machinery to produce more viruses through a lytic or lysogenic infection cycle.

1. BACTERIABACTERIA
TSW investigate and understandTSW investigate and understand
the life functions ofthe life functions of
Archaebacteria and EubacteriaArchaebacteria and Eubacteria

2. Prokaryote DiversityProkaryote Diversity
Earth’s most abundant life formsEarth’s most abundant life forms
Capable of surviving in many differentCapable of surviving in many different
environmentsenvironments
Capable of getting energy from many differentCapable of getting energy from many different
sourcessources

3. Prokaryote ReviewProkaryote Review
Mostly single-celledMostly single-celled
NO nucleus orNO nucleus or
organellesorganelles
CircularCircular
chromosomeschromosomes
Cell wallsCell walls
Mostly asexualMostly asexual
Anaerobic or aerobicAnaerobic or aerobic
Heterotrophic orHeterotrophic or
autotrophicautotrophic

4. ARCHAEBACTERIAARCHAEBACTERIA
No peptidoglycan in their cell wallNo peptidoglycan in their cell wall
DNA sequences are more similar to thoseDNA sequences are more similar to those
of Eukaryotes than Eubacteriaof Eukaryotes than Eubacteria
Live in extremely harsh environmentsLive in extremely harsh environments

5. EUBACTERIAEUBACTERIA
Larger of the 2 KingdomsLarger of the 2 Kingdoms
Tremendous variety…live almost anywhereTremendous variety…live almost anywhere
Cell wall of peptidoglycanCell wall of peptidoglycan
Usually contain 1 or 2 cell membranesUsually contain 1 or 2 cell membranes

6. Identifying BacteriaIdentifying Bacteria
ShapeShape
Cell WallCell Wall
How they moveHow they move
How they obtain energyHow they obtain energy

7. Bacteria are named by SHAPEBacteria are named by SHAPE
Cocci (ball-shaped)Cocci (ball-shaped)

StreptococcusStreptococcus
mutansmutans
Bacillus (rod-shaped)Bacillus (rod-shaped)

ClostridiumClostridium
botulinumbotulinum
Spirilli (spiral-shaped)Spirilli (spiral-shaped)

TreponemaTreponema
palladiumpalladium

9. ConjugationConjugation
Sexual (exchangeSexual (exchange
of genetic materialof genetic material
between bacteria)between bacteria)
A hollow bridgeA hollow bridge
forms between twoforms between two
bacteria and genesbacteria and genes
move from one cellmove from one cell
to anotherto another

10. Importance of BacteriaImportance of Bacteria
Producers that capture energy byProducers that capture energy by
photosynthesisphotosynthesis
Decomposers- breaking down theDecomposers- breaking down the
nutrients in dead matter & the atmospherenutrients in dead matter & the atmosphere
Fix nitrogenFix nitrogen
Human uses (food, digestion, medicines)Human uses (food, digestion, medicines)

11. What is a virus?What is a virus?
A typical virus isA typical virus is
composed of a corecomposed of a core
of DNA or RNAof DNA or RNA
surrounded by asurrounded by a
protein coatprotein coat
ALL viruses enterALL viruses enter
living cells & use theliving cells & use the
machinery of themachinery of the
infected cell toinfected cell to
produce more virusesproduce more viruses

12. Viral StructureViral Structure
CapsidCapsid: protein: protein
coat that enables acoat that enables a
virus to enter avirus to enter a
host cellhost cell
Proteins within theProteins within the
capsid bind withcapsid bind with
receptors on thereceptors on the
surface of the hostsurface of the host
cell & trick it intocell & trick it into
allowing it insideallowing it inside

13. Viral InfectionViral Infection
Once the virus isOnce the virus is
inside the host cell,inside the host cell,
2 things can2 things can
happenhappen

Lytic InfectionLytic Infection

LysogenicLysogenic
InfectionInfection

14. Lytic InfectionLytic Infection
The BasicsThe Basics: Virus: Virus
enters a cell,enters a cell,
makes copies ofmakes copies of
itself, & causes theitself, & causes the
cell to burstcell to burst
KEY POINTKEY POINT: Host: Host
cell is LYSED andcell is LYSED and
destroyeddestroyed

15. Lysogenic InfectionLysogenic Infection
The BasicsThe Basics: Virus integrates its DNA into: Virus integrates its DNA into
the DNA of the host cell, & the viralthe DNA of the host cell, & the viral
genetic info replicates along with the hostgenetic info replicates along with the host
cell’s DNAcell’s DNA
KEY POINTKEY POINT: Host cell makes copies of: Host cell makes copies of
the virus indefinitely; the host cell is NOTthe virus indefinitely; the host cell is NOT
destroyed right awaydestroyed right away

16. Are viruses ALIVE?Are viruses ALIVE?
No if we require that living things be madeNo if we require that living things be made
up of cells & be able to live independentlyup of cells & be able to live independently
However, have many characteristics ofHowever, have many characteristics of
living thingsliving things

Regulate gene expressionRegulate gene expression

Able to evolveAble to evolve