Classification

1. Classification The evolution of Complexity: single cell prokaryote to multicellular eukaryotes

2. Aristotle to Linneaus Taxonomy- classifying organisms Binomial nomenclature and scientific names Canis lupus, Turdis migratoris, Felis catus Systematics- the study of biodiversity and its classification, create phylogenies Phylogeny- an organism’s evolutionary history, a phylogenetic tree

3. Modern Classification System • Domain Archea, Eubacteria, and Eukarya • Kingdom Archeabacteria, Eubacteria, Protista, Fungi, Plant, Animal • Phylum • Class • Order • Family • Genus First part of Scientific name • Species Second part of Scientific name

4. The Evolution of Complexity • Earth is approximately 4.5 billion years old • 1st living things, prokaryotic bacteria cells are found in the fossil record dating 3.5 billion years ago • 1st eukaryotic cells appear in fossil record dating 2.1 billion years ago • Between 635-530 million years ago the fossil record shows the diversity of algae and small animal like organisms

5. Origin of Life • Spontaneous Generation: life from non-life was replaced with – Biogenesis • Oparin’s hypothesis of the origin of life was tested by Miller and Urey, creating organic compounds but not life • Endosymbiosis- the hypothesis behind the evolution of eukaryotes from prokaryotes

6. What is a Virus?- nonliving… Composed of genetic material, RNA or DNA, and a protein coat Genetic material surrounded by a protein coat, must have a host cell in order to reproduce Life cycles:Lytic (kills host cell) or Lysogenic (incorporates DNA into host)

7. Human viral diseases Virus- disease • Flavivirus- Yellow Fever • HIV- AIDS • Herpes virus 3- Chicken pox • Filovirus- Ebola • Hepatitus B- Hepatitus • Influenza virus- Influenza or pneumonia • Epstien- Barr virus- Mono • Polio virus- Polio • Rhabdovirus- Rabies • Voriola virus- Smallpox • Paramyxovirus- Mumps

8. 3 Domains • Archea • Eubacteria • Eukarya Bacteria once belonged to the same Kingdom, Monera, but through Molecular Biology and the study of evolution, Biologist realized they had critical differences and should be placed into their own category so the “Domain” classification level was created.

9. 6 Kingdoms

10. Archea and Eubacteria • Archea Kingdom All prokaryotic single celled organisms. No Peptidoglycan in cell wall Most ancient and extreme They live in the harshest environments Methanogens (anaerobic), thermoacidophiles (hot) and halophiles (salty) • Eubacteria Kingdom True bacteria, all prokaryotic single celled Have Peptidoglycan in cell wall Classified by their shape and gram staining Gram + have more peptidoglycan and stain purple Gram – have less peptidoglycan and stain pink

11. Shapes and Examples • Sphere- Cocci, can occur in chains Streptococcus Pneumoniae which can cause strep throat or Scarlet fever, or grapelike clusters Staphylococcus aureus which can cause skin infections and Toxic Shock syndrome • Rod- Bacillus ex Escherichia coli (E.coli), Lactobacilli which can cause tooth decay or one strain makes Sourdough bread, other bacilli can cause botulism, typhoid fever, and anthrax • Spiral- Spirilla comes in 3 shapes 1. Vibro which is curved caused Cholera, 2. Spirillum (thick spiral), and 3. Spirochete (thin spiral) ex. Treponema pallidum causes Syphilis and another strain can cause Lyme disease

12. Images of bacteria Syphilis and Cholera Strep- chain Staph - cluster E. coli

13. Essential Bacteria: ecosystems depend on these small organisms • Cyanobacteria- photosynthetic/producers, building blocks of most aquatic food webs • Nitrogen- Fixing Bacteria- symbiotic relationship with plants, they help them absorb nitrogen from the soil. • Helpful: fermentation, digestion, biotechnology, nitrogen fixing, decomposers, oxygen producers • Antibiotics kill bacteria by destroying the cell wall, gram negative have an extra lipid layer that prevents the antibiotics from entering the cell.

14. Reproduction • Bacteria reproduce asexually, binary fission • Each bacteria has a single chromosome but can have additional DNA in the form of plasmids. • Plasmids increase Bacterial genetic variation and contribute to Bacteria evolution • Plasmids can be exchanged between different bacteria (even different species) by a process called conjugation. • Plasmids can also be taken up by bacteria from their environment via transformation. • Additional DNA recombination can be introduced via a bacteriophage, this is called transduction.

15. All bacteria: Reproduce asexually Single celled Have cell wall Single strand of DNA Some Bacteria: Autotrophic Heterotrophic Some move by flagella, slime, spiral motion Some produce endospores which allow them to go dormant during hostile conditions Some produce toxins Review of Bacteria

16. Kingdom Protista • Kingdom of Mostly single celled organisms • Categorized by their likeness to 3 other kingdoms • All Eukaryotic some Autotrophic and some Heterotrophic

17. Algae- Plant like Protist • Algae or Plant-like, Autotrophic, classified by pigment with no cell wall, come form elaborate colonies and multicellular structures (kelp and seaweed) • Chrysophyta- Golden Algae ex diatoms • Pyrrophyta- bioluminescent/glow ex. Dinoflagellates • Euglenaphyta- ex Euglena • Rhodophyta- red • Phaeophyta- brown, seaweed and kelp • Chlorophyta- green, ex Volvox, Spirogyra

18. Images of algae • Volvox • Spirogyra • Red algae • Seaweed • Kelp • Diatoms

19. Protozoa or Animal like Protist Protozoa or Animal-like, classified by mode of movement • Sarcodina ex. Amoeba- move by pseudopodia “false foot” • Ciliophora ex Paramecium- move by cilia, tiny hairs • Zoomastigina ex Trypanosoma (African Sleeping Sickness) moves by flagella • Sporozoa, are the parasitic animal like protista, include Plasmodium which causes Malaria

20. Images of Protozoa • Amoeba • Paramecium • Trypanosoma

21. Fungus-like Protista • Fungus-like are all Heterotrophic with no cell wall, absorbing nutrients directly through cell membrane • Include Plasmodium or Slime Molds and Downy Mildews

22. Kingdom Fungi • All Eukaryotic, multicellular, heterotrophs (saprotrophs or detrivores living off dead and decaying organisms or decomposers), cell wall made of chitin (type of protein), and classified by reproductive structures. • Mycoses is the term for Fungal Infection, Fungus destroys the cells around the infection site, to fight fungal infection you have to destroy the cell wall • Fungi are important part of an ecosystem because they recycle nutrients/ decomposers

23. Classifications of Fungi • Club Fungi – Basidiomycota , Basidia, ex Mushrooms • Sac Fungi- Ascomycota, Asci, ex. Truffles, Morels,Yeast, and Athletes Foot Fungus • Zygote Fungi – Zygomycota, Sporangia, ex. Bread molds • Imperfect- Deuteromycota, reproduce asexually, ex Penicillian • Lichen- Mycophycophyta, symbiotic relationship between fungus and photosynthetic cells of cyanobacteria or algae.

24. Images of Fungi

25. Kingdom Plante • Multicellular, Eukaryotic, Cell wall made of cellulose, Autotrophs, not capable of movement, reproduce sexually some produce spores and others seeds. • Most have vascular tissues which include roots, stems, and leaves, and specialized tissues called xylem and phloem.

26. Plant evolution • Evolved from green algae, 400-450 mya • Evidence: they both… • Chlorophyll a, b, and carotenoids • Thylakoid membranes • Cell walls of cellulose • Stored carbohydrates as starch **Primitive plants were aquatic, but adaptations have allowed them to be successful on land.

27. Plant evolution cont’d • Adaptations to terrestrial life • Cuticle (leaf)- keep water in • Stoma (leaf)- control gas exchange • Development of specialized tissues leaf, root, stem, root hairs, vascular tissue • Symbiosis with fungi and bacteria to increase nutrient uptake • Secondary growth- lateral meristem to thicken structures • Spores and seeds not dependent on water

28. Basic Plant Anatomy • The leaf • Cuticle - Vascular bundles • Stoma - mesophyll

29. Alternative Pathways in Photosynthesis involve evolution in leaf anatomy and storage of CO2 within the leaf

30. Figure 10.20 A review of photosynthesis

31. “C3” Plants

32. Photosynthesis relies on CO2 entering the leaf and O2 leaving the leaf Leaf surfaces contain stomata 18 µm Pore Stoma Guard cells

33. Carbon dioxide diffuses into leaves through stomata H2O Leaf cross-section BUT: water also escapes through the stomata CO2

34. Remember… the roles of H2O and CO2 in photosynthesis? • H2O is needed for PSII in the light reaction to produce ATP • CO2 is needed for the Calvin Cycle and Carbon Fixation into G3P

35. Photosystem II Photosystem I ETC of Photosynthesis chlorophyll a chlorophyll b

36. Noncyclic Photophosphorylation • Light reactions elevate electrons in 2 steps (PS II & PS I) • PS II generates energy as ATP • PS I generates reducing power as NADPH ATP

37. Cyclic photophosphorylation • If PS I can’t pass electron to NADP…it cycles back to PS II & makes more ATP, but no NADPH • coordinates light reactions to Calvin cycle • Calvin cycle uses more ATP than NADPH  ATP 18 ATP +12 NADPH  1 C6H12O6

38. NADP Photophosphorylation cyclic photophosphorylation NONcyclic photophosphorylation ATP

39. Another problem for C3 plants • Photorespiration is a process in plant metabolism by which RuBP (a sugar) has oxygen added to it by the enzyme (rubisco), instead of carbon dioxide during normal photosynthesis • Photorespiration can occur when carbon dioxide levels are low, for example, when the stomata are closed to prevent water loss during drought. In most plants, photorespiration increases as temperature increases. Photorespiration produces no ATP and leads to a net loss of carbon and nitrogen (as ammonia), slowing plant growth. • Potential photosynthetic output may be reduced by photorespiration by up to 25% in C3 plants.

40. C4 plants sequester CO2 in certain cells CO2 CO2 stored in mesophyll cell Organicacid C4 pathway CO2 CO2 used inadjacent bundle sheath cell Calvin cycle G3P Examples of C4 plants: corn, sugarcane, many grasses

41. Figure 10.18 C4 leaf anatomy and the C4 pathway

42. C4 Plantsinclude sugar cane and corn

43. CAM plants sequester CO2 at night CO2 CO2 storedat night Organicacid C4 pathway CO2 Calvincycle CO2 usedduring the day G3P Examples of CAM plants: pineapples, cacti, and most succulents.

44. CAM Plants Photosynthetic adaptation to arid conditions evolved in many succulent, water-storing plants: cacti, pineapples

45. Figure 10.19 C4 and CAM photosynthesis compared

46. Spore Producing Divisions of Plant 9 Phyla of Plants: can be divided into spore or seed producers Spore producers • Bryophytaonly nonvascular plants, ex moss and liverwort (gametophyte dominant stage of life cycle know as alternation of generations) • Lycopodophytaex. 1,000 species of Club and Spike moss • Pterophytes12,000 species of ferns, horsetails, and whisk ferns have compound leaves called fronds (dominant stage is the sporophyte)

47. Spore producing plant images

48. Seed producers • Gymnosperms: reproductive structure is the cone , “naked seed” • Cycadophyta 130 species of these tropical plants • Ginkgophyta 1 species remains the Gingko tree • Coniferophyta 600 species of conifers, pine, spruce, cypress, juniper, fir • Gnetophyta75 species of these arid/semi-desert dwelling plants

49. Seed producers Angiosprems- reproductive structure is the flower, seeds are surrounded by fleshy or dry fruit that ripen to encourage animals to disperse the seeds. 30,000 or more identified species maple, hickory, oak, aloe, roses, tulips, dogwood, magnolia, corn, beans, tobacco, apple tree, pecan tree 2 classes: Monocots – with one seed leaf or cotyledon and parallel veins on the leaf, orchids, lilies, grass, corn, grains Dicots- with two seed leafs and branched veins on the leaf, roses, peas, beans, and oaks

50. Seed producers- gymnosperms “Cone Bearers”