Endosymbiosis

1. Endosymbiosis FLASHBACK

2. Kingdom Protista

3. Kingdom Protista Single-Celled Multicellular Disease causing pathogens Eukaryotic Overiew;Protist Clip heterotrophic or autotrophic Have a Nucleus Generally aquatic Mixotrophs

4. Can be “grouped” byMethod of Nutrition Animal-like “protozoa” Fungi-like Plant-like “algae like” Absorption Heterotrophic Autotrophic

5. Plant-Like Animal-Like Fungi-Like

6. Animal-Like Classified based on Means of Locomotion 5 important phyla 1- 2-(Rhizopoda) 3- (Forams) 4- 5-

7. Ciliophora • The Ciliophora (ciliates), a diverse protist group, is named for their use of cilia to move and feed. Stentor Paramecium

8. Move by Cillia Helps regulate water level • Fresh or salt water • Most Ciliates are free-living Locomotion Oral Groove Waste Removal Paramecium

9. macronucleus controls the everyday functions of he cell micronuclei -required for sexual processes

10. Ciliated generally reproduce asexually by binary fission of the macronucleus, rather than mitotic division. The micronuclei (with between 1 and 80 copies) are required for sexual processes that generate genetic variation.

11. The sexual shuffling of genes occurs during conjugation, during which micronuclei that have undergone meiosis are exchanged. In ciliates, sexual mechanisms of meiosis and syngamy are separate from reproduction.

12. Paramecium Conjugation

13. Sporozoa • Parasites of animals • Nonmotile • Release spores • Cause malaria • strictly parasitic protozoans that are usually immobile Plasmodium falciparum Malaria Clip

14. Clip • Plasmodium, the parasite that causes malaria, spends part of its life in mosquitoes and part in humans.

15. The incidence of malaria was greatly diminished in the 1960s by the use of insecticides against the Anopheles mosquitoes, which spread the disease, and by drugs that killed the parasites in humans. • However, resistant varieties of the mosquitoes and the Plasmodium species have caused a malarial resurgence. • About 300 million people are infected with malaria in the tropics, and up to 2 million die each year. -transmitted by the bite of an Anopheles mosquito

16. Cryptosporidiosis • diarrheal illness • acute short-term infection but can become severe and non-resolving in children and immunocompromised individuals Cryptosporidium

17. Illness is usually minor • If weakened immune system, could be fatal Toxoplasmosis Toxoplasma gondii.

18. Zooflagellates • Move with flagella • Some mutalistic w/termites • Others are parasites • Trypanosoma transmitted by the tsetse fly causes African sleeping sickness

19. Termites Symbiosis Trichonympha

20. Giardia lamblia, a parasite that infects the human intestine. • 2 nuclei, multiple flagella • The most common method of acquiring Giardia is by drinking water contaminated with feces containing the parasite in a dormant cyst stage

21. Rhizopoda • Amoebas • Move by pseudopods • Engulf food by phagocytosis

22. Move by Pseudopods

23. Clip

24. Foraminifera • Porous shells called “tests” • test-a technical term for internal shells • Hardened CaCO3 • Pseudopodia extend through the pores • Some species are geologically short-lived and some forms are only found in specific environments. Therefore, a paleontologist can examine the specimens in a small rock sample like those recovered during the drilling of oil wells and determine the geologic age and environment when the rock formed.

25. Plant-Like • Eukaryotes • Most unicellular, but some multicellular • Autotrophic – contain chlorophyll & make food by photosynthesis Found in freshwater, marine, and moist soil habitats • Range in size from microscopic to seaweeds hundreds of feet in length 10

26. algae Volvox Plant-like Protist Clip Spirogyra Chlamydomonas

27. Phytoplankton (including planktonic eukaryotic algae and prokaryotic cyanobacteria) are the bases of most marine and freshwater food chains.

28. Red Algae Green Algae Phyla • Euglenophyta • Euglenoids • Dinoflagellata • Dinoflagellets • Bacillariophyta • Diatoms • Chrysophyta • Golden Algae • Chlorophyta • Green Algae • Phaeophyta • Brown Algae • Rhodophyta • Red Algae Algae Diatoms Golden Algae

29. Euglenophyta • Euglenoids • 1, 2 or 3 flagella • Pellicles- protein strips- outside of their membrane • Mixotrophic • Eyespot permits phototaxis

30. -Euglena, a single celled mixotrophic protist, can use chloroplasts to undergo photosynthesis if light is available or live as a heterotroph by absorbing organic nutrients from the environment. Euglenophyta Unique glucose polymer, paramylon, as a storage molecule

31. Euglena Detects light • Contractile vacuole to pump out excess water • Chloroplasts to make food by photosynthesis • Can be heterotrophic in the absence of light Most live in freshwater, but some live in moist soil & the digestive tracts of certain animals

32. Clip Dinoflagellata • Two flagella sit in perpendicular grooves and produce a spinning movement. • Some are bioluminescent • Some produce nerve toxins • The dinoflagellates are abundant components of the phytoplankton that are suspended near the water surface. • Dinoflagellates and other phytoplankton form the foundation of most marine and many freshwater food chains.

33. Some dinoflagellates are heterotrophic. • Most dinoflagellates are unicellular, but some are colonial. • Each dinoflagellate species has a characteristic shape, often reinforced by internal plates of cellulose.

34. Dinoflagellate blooms, characterized by explosive population growth, cause red tides in coastal waters. The blooms are brownish-red or pinkish-orange because of the predominant pigments in the plastids.

35. They release a neurotoxin into the environment. Shellfish concentrate this toxin and it can kill people who eat the contaminated shellfish. Also produce massive invertebrate and fish kills. These toxins can be deadly to humans as well

36. Bacillariophyta • Diatoms • Two silica (SiO2) shells that overlap like a shoe box.

37. Diatoms

38. Chrysophyta • Golden algae (Chrysophyta), named for the yellow and brown carotene and xanthophyll pigments, are typically biflagellated. • Some species are mixotrophic and many live among freshwater and marine plankton. • At high densities, they can form resistant cysts thatremain viable for decades.

39. While most are unicellular, some are colonial.

40. Chlorophyta • Green algaeare named for their grass-green chloroplasts. • These are similar in ultrastructure and pigment composition to those of plants. • The common ancestor of green algae and plants probably had chloroplasts derived from cyanobacteria by primary endosymbiosis. • Believed to be the ancestors of plants

42. Most of the 7,000 species of chlorophytes live in freshwater. • Other species are marine, inhabit damp soil or snow, or live symbiotically within other eukaryotes. • Some chlorophytes live symbiotically with fungi to form lichens, a mutualistic collective. • Chlorophytes range in complexity, including: • Biflagellated unicells that resemble gametes and zoospores. • Colonial species and filamentous forms. • Multicellular forms large enough to qualify as seaweeds.

43. Large size and complexity in chlorophytes has evolved by three different mechanisms: (1) The formation of colonies of individual cells (Volvox) (2) the repeated division of nuclei without cytoplasmic division to form multinucleate filaments (Caulerpa). Volvox Caulerpa

44. (3) The formation of “true” multicellular forms by cell division and cell differentiation (Ulva). Ulva-sea lettuce

45. Chlorophyta Life Cycle of Chlamydomonas(Alternation of Generations) Clip Syngamy-the union of two gametes to form a zygote

46. Phaeophyta • Brown algae (Phaeophyta) are the largest and most complex algae. • Most brown algae are multicellular. • Most species are marine. • Brown algae are especially common along temperate coasts in areas of cool water and adequate nutrients. • They owe their characteristic brown or olive color to accessory pigments in the plastids.

47. The life cycle of the brown alga Laminaria is an example of alternation of generations. The diploid individual, the sporophyte, produces haploid spores (zoospores) by meiosis. The haploid individual, the gametophyte, produces gametes by mitosis that fuse to form a diploid zygote. Clip

48. Structural and biochemical adaptations help seaweeds survive and reproduce at the ocean’s margins • The largest marine algae, including brown, red, and green algae, are known collectively as seaweeds. • Seaweeds inhabit the intertidal and subtidal zones of coastal waters. • This environment is characterized by extreme physical conditions, including wave forces and exposure to sun and drying conditions at low tide.

49. Seaweeds have a complex multicellular anatomy, with some differentiated tissues and organs that resemble those in plants. • These analogous features include the thallus or body of the seaweed. • The thallus typically consists of a rootlike holdfast and a stemlike stipe, which supports leaflike photosynthetic blades.

50. Some brown algae have floats to raise the blades toward the surface. • Giant brown algae, known as kelps, form forests in deeper water. • The stipes of these plants may be 60 m long. Holdfast of a kelp