Prokaryotes

1. Prokaryotes Chapter 19

2. Y. pestis (cause of bubonic plague) Prokaryotes! • The small wonder… First inhabited the earth ____________! • Continued to rule alone for 1.5 billion years until they gave rise for more complex organisms • Still exist today (bacteria) and are still one of the most fierce predators, as well as important helpers associated with human health. • Have ____________ • Even though they are in ________ _____________________they are very similar in morphology • Generally single celled ESCHERICHIA COLI is a type of bacteria that lives in the intestinal tract, aiding the digestive process by suppressing the growth of harmful bacteria and synthesizing vitamins

3. Prokaryotes are broken into two major groups… diverged a long time ago Archaea • Has its ______________ ____________(some match Eukaryotes) • Use ________________ ____________similar to eukaryotes • _____________________ • Some Carbon chains, mostly branched Bacteria • Has unique rRNA sequences • Replicates with _______ ____________________ • _____________________________________cell wall (Gram Stain) • Unbranched carbon chains in the membrane lipids

4. Prokaryotes are divided by the way they get nourishment • Earliest life needed to be autotrophs (make their own food). Need Energy (make ATP… to do so they need a carbon source!) • Photoautotrophs: Energy from ______________… carbon from _______(Cyanobacteria… No Archaea just bacteria) • Chemoautotrophs____________________________ and break their bonds for energy… get their carbon from ______(many Archaea metabolize this way)

5. More Prokaryote divisions Purple bacteria • Once some Autotrophs existed organisms can start eating other organisms (_________________) • Photoheterotrophs: Energy from ___________, Carbon from ________ _________________ (some purple and green bacteria) • Chemoheterotrophs: Get energy by _________________________, also get their carbon from _____________ ______________ (similar to animals… largest group, includes E. coli and SOME Archaea) Anthrax (Bacillus anthracis )

6. Archaea

7. Archaea are found in unusually harsh environments • Very similar to Eukaryotes in many of their DNA sequences • Can obtain nutrients in the same ways and be the same size as bacteria • Resemble ancient life because they live in environment close to the original earth’s environment • Extreme halophiles: Live in ______________________ like the dead sea • Extreme thermophiles: Live in _____________________ • Methanogens: Live without oxygen and _________________

8. Bacteria

9. Bacteria come in 3 basic shapes • Spherical shaped (Cocci), often in clumps (streptococcus: strep throat) • Rod-Shaped (often called _________) and live singularly… not touching • Curved or Spiral shaped (vibros, spirilla or ______________). Syphilis is caused by a spirochete

10. Some bacteria cause disease... • Any disease causing agent is called a _______________________ • Half of human diseases are caused by pathogenic bacteria • Classified into two mechanisms • ___________ Producing: • Bacteria ________________ that is pathogenic • usually VERY dangerous… just a little infection can kill you) • Ex: Clostridium botulinum • _________________Producing: • Bacteria themselves _____________ _____________________________ • generally more mild but do include major illness like food poisoning and typhoid fever Vibrio cholerae causes a life-threatening diarrhea using both endo and exo toxins

11. Virulence and Prevention • Virulence of a pathogen is measured by LD50… the amount of pathogen that will kill 50% of those exposed to it • The __________________________ __________________________and dangerous the microbe. • With bacteria most treatments are _______________ and the best way to prevent onset is with good _______________________ The Komodo dragon carries at least 3 strains of highly virulent bacteria in its mouth…this way it __________________________ ____________________________

12. Current uses for Bacteria • Biological warfare: Not a new idea… • during the Middle Ages plague victims were used as ‘bombs’ and tossed into enemy lines • Europeans unknowingly and knowingly gave bacterial (and viral) infections to the people they were trying to concur (Yellow fever and the American Indians ring a bell?) • US started using researching anthrax, as well as botulism back in 1943 • Now this bioterrorism is becoming a threat to the US… Anthrax easily spreads and aerosolizes

13. Not all bacteria are bad! (Bioremediation) • Cleaning the environment: Bacteria can also be used for good • Used to ______________________ _____________________(clean out septic tanks and help keep pipes flowing) • ____________________(there are natural bacteria that metabolize oil waste and they can be cultivated to clean up habitats that have been damaged by humans)

14. It’s diversity that helps prokaryotes continue to survive • Unique structural features that allow prokaryotes to make up for their small singular size… • Prokaryotic ____________ (allows for locomotion) • _________(allows for adhesion to a favorable environment) • _____________ : Resting structure for bacteria in an unfavorable environment… lets it hang out until conditions get better (used like seed in plants) • Clostridium and Bacillus anthraces form endospores

15. Eukaryotes Chapter 20

16. Review • Prokaryotes: Domains Archaea and Bacteria • Protista: The Junk Kingdom • Fungi • Plantae • Anamalia Right Now Before the Final

17. In the beginning (or a couple million years later) • Eukaryotes evolved from prokaryotes using a couple cool features • Membrane infolding…When the ________________________ ___________________________________________ (like ER) • ______________________… One cell living within another, benefiting both (like Mitochondria and chloroplasts)

18. Do you have a junk drawer? • The protista are a junk kingdom… which is really probably a lot of kingdoms • They are placed together because they don’t fit in the other kingdoms, not because they have something in common. • They can be classified by how they look– but DNA doesn’t always agree Fungus- like Protists Ancient Protists Plant- like Protists Animal- like Protists

19. For now we’ll go with this • Protista is broken into 3 major groups based on their lifecycle… most groupings are non-monophylogenetic. • Diploid dominant (like animals) • Alternation of generations (like plants) • Haploid/ gametophyte dominant (like fungi) **Note– these are not evolutionary linages

20. Dominant Diploid Generation • Diploid dominant… heterotrophic and sometimes parasitic • Flagellates: __________________, include Giardiawhich lives in the intestine, and Trypansoma which lives in the blood and causes African sleeping sickness • Shelled Amoebas: Secrete a shell then extend their ______________ (fake feet)out to move, they also use them for endocytosis • Alveolates... Next page Giardia

21. Dominant Diploid Generation… continued Alveolates • Apicomplexa: specialized with complex organelles for being a ___________________. Include Plasmodium which causes malaria • Ciliates: Move via cilia. Have 2 kinds of nuclei (1 macro and several micro) ______________ ______________________. Live in aquatic environments • Some _____________: Although they ARE alveolates we will discuss them with Algae because most are photosynthetic

22. Alternation of Generations • When a species alternates LIVE GENERATIONS. • It lives _____________ ___________________ • Plants have distinct alternations… so do these next protista

23. Unicellular Algae • Act like single celled plants… (photosynthetic, autotrophic)… not a monophyletic group • Dinoflagellates: distinct look per species. Two flagella that cause them to spin around. _________________________________________and can be deadly. (some _________) • Diatoms: Huge marine food source. Have a shell made of __________ (look glassy). Float near the surface of the ocean • Green Algae: single celled, multiple life stages… more to come

24. More on Green Algae • ________________________________________________________________________________________________________________________ • Their early evolution can be ‘seen’ in modern species • Chlamydomonas seems to be the precursor to Volvox. • When Volvox reproduces the cells that leave (red or green biflagellate cells) look like those of Chlamydomonas. • When Volvox is in its growth state it appears as an aggregation of those same Chlamydomonas- like cells

25. Multicellular Algae • Most complex algae… • ______________________________________________________________________________________________________ • Brown algae (not all brown) ______________ _________________________, diverged from diatoms. Form large kelp forests that are indispensable to fish, otters and even gray whales (have “hold fasts” instead of roots) • Red Algae: can __________________. Life in tropical waters and play an important role in reef building (have unicellular members– dinoflagellates) • Multicellular green algae:_____________ ___________________(like many plants do). This is a cycle of haploid and diploid organisms being formed

26. Cellular Slime Molds • Gametophyte dominant • Unicellular and multicellular life stages • ________________________________________________________… making them fungus-like • CASE EXAMPLE: Dictostelium • Feeds on bacteria… if they are plentiful it leads a happy solitary, single celled (amoeboid) life. Reproducing by mitosis and moving very little. • When bacteria is scarce the _______ ______________________________ (using cAMP signals) to form a colony with more motility. • Moves to what it thinks might be a better place __________________ ______________________________ (the colony differentiates its cells… crazy)