1. Bacteria & Protists
Conjugation
Binary fission

2. Bacteria and early life
The __________ life-form was bacterial, ~ 3.8 bya
Some were probably __________________
“chemo-” = extract energy from _______ compounds
“auto-” = synthesize sugars from ____
Others got energy by _________ respiration of sugars
__ was rare in early Precambrian
~3.0 bya, _____________ bacteria appear
Very successful, worldwide
Released __ as a byproduct of ____
Changed Earth’s atmosphere
Bacteria > early life

3. Photosynthetic membranes of individual bacterium
Living mats of bacteria
Stromatolites: fossilized mats of photosynthetic bacteria

4. The major branches of life
Kingdoms:
______
(external
digestion)
_________
(photosynthetic)
________
(ingest food)
Multicellular
Unicellular
Domains:
Prokaryotic
cell design
Eukaryotic
1st cellular organism

5. Protists: single-celled organisms
Taxonomy of protists changed as knowledge improved
1700s – 1800s: K:Plantae, K:Animalia
New knowledge:
Fungi are not photosynthetic
Bacterial cells differ greatly from plant & animal cells
Early 1900s: K:_______, K:Fungi, K:Plantae, K:Animalia
New knowledge:
Some single-celled creatures are equally plant & animal
Late 1900s: K:Monera, K:Fungi, K:Plantae, K:Animalia, K: ______
New knowledge:
Archaebacteria are much different than all other life-forms
Differences between protist taxa are greater than plant vs. animal
~ 2000: 3 _______: Bacteria, Archaea, Eukaryota
Many (20?) Protist Kingdoms within Eukaryota
Protists

6. Only superficially similar to ______ bacteria
Archaebacteria
Only superficially similar to ______ bacteria
Unique cell membrane & cell wall
Rare today
____________: live in extreme environments
Geothermal pools, salt lakes, deep sea ____
Bacteria > Archaebacteria

7. Eubacteria (_________ Bacteria)
General features:
Cell wall (________ to plants’)
Pili: ‘hairs,’ stick to _________
Sex ____ for conjugation
Exchange of ____
Endospore (in many species)
Thick wall
Resists _________, heat, chemicals
Can remain dormant for _________
Must _________ at 250oF to destroy
Bacteria > Eubacteria

8. Most abundant life-form today
Taxonomy based on: 1) ________ of cell wall
Gram positive (stain ________):
Anthrax
Thick wall made of ____________acid
Gram negative (stain ________):
Thin wall covered by outer membrane
2) shape:
1) Cocci, ________
e.g., Gonococcus
2) Bacilli, r________
e.g., Anthrax
3) Spirochete, _____
e.g., Syphilis
Bacteria > Eubacteria

9. ~ 1/1,000 as much DNA as eukaryotic cells
Prokaryotic DNA
~ 1/1,000 as much DNA as eukaryotic cells
Occurs as a single ________ chromosome
Contains all _________ genes
Can also have small circular DNA _______
DNA
Plasmid
Conjugation
tube
(cell 1)
(cell 2)
Contains genes for _______circumstances
e.g., antibiotic resistance
Can be exchanged between cells
By conjugation
Allows “_____” of useful traits
Scientists use plasmids to insert
and clone _______
Bacteria > Eubacteria > genetics

10. Prokaryotic protein synthesis
Transcription and translation occur ________
Prokaryotes have no nuclear membrane
________ translate mRNA as it is transcribed
Simple, more direct than eukaryotes
DNA
Ribosome
Messenger RNA
Protein
transcription
translation
Bacteria > Eubacteria > genetics

11. Ecological roles of modern bacteria
Many have _____ byproducts that cause disease:
E.g, plague, TB, cholera, anthrax
Others are ________ recyclers:
1) Decomposers:
Break down ________wastes
2) Fixers:
Make ______ available to plants & animals
E.g., nitrogen-________ bacteria
Live in root ______ of legume plants
Convert N gas into _____ N compounds
A type of ________
Bacteria provide N, plants provide _______
Bacteria > Eubacteria > ecology

12. Single-celled Eukaryotes
Paramecium
Protist Kingdoms:
Single-celled Eukaryotes
Appeared ~__ bya
Evolved from __________
Through endosymbiosis
E.g., photosynthetic bacterium became
_________ of eukayrotic cell
Can be animal-like, plant-like, or fungus-like
Formerly included in those kingdoms
Occur in all _______ environments
Including _______ other eukaryotes
Protists

13. 1) Animal-like protists
Unifying feature: _____ food, digest it internally
a. Flagellates
Move by flagella
Trypanisoma
Giardia
Protists > Flagellates

14. b. Ciliates
Move by cilia
Protists > Ciliates

15. Move by pseudopodia – “________” Edge of cell spreads like “The Blob”
c. Amoebas
Move by pseudopodia – “________”
Edge of cell spreads like “The Blob”
Pseudopodia
Protists > Amoebas

16. 2) Plant-like protists: Unicellular algae
Most are photosynthetic
a. Green algae
-__________
-2 flagella
-Cell wall contains _______
Protists > unicellular algae > green algae

17. Cell wall contains ____ (glass)
b. Diatoms
Cell wall contains ____ (glass)
Very abundant in the sea
Form ‘diatomaceous earth’
and _____ foam
Protists > unicellular algae > diatoms

18. 3) Fungus-like protists: e.g., slime molds
_________ digestion, no ingestion
Eat decaying matter and bacteria
Can have uni- and multicellular ______
Lack of ____ initiates stage transition
Multicellular slime mold “slug”
Protists > fungus-like

19. 1) Food becomes depleted
Life cycle of slime molds:
3) Fruiting bodies
bear ______
4) Amoeboid generation
emerges from spores,
eats food
_______ body develops
Slime mold cells
cover food
2) Food source found,
1) Food becomes depleted
Multi-cell _____ forms, moves
Protists > fungus-like