The document summarizes key information about animal-like protists (protists without chloroplasts). It discusses their modes of locomotion/movement including cilia, flagella, and pseudopodia. It also describes their various modes of reproduction like binary fission, conjugation, and fragmentation. The major groups of protists are identified including ciliates, dinoflagellates, apicomplexans, amebas, and others.

1. Animal-like Protists

2. Core Concepts Animal-like protists usually are unicellular eukaryotic organisms. The absence of choroplasts and chlorophyll distinguishes these organisms from plant-like protists. Most protozoans are microscopic in nature and are seen usually in freshwater environment.

3. There are four major groups of protists based primarily on their modes of locomotion/movement: ciliophora (cilia-bearing), zoomastigina (flagella-bearing), sporozoa (in fluids as parasites) and sarcodina (with pseudopodia)

4. Different modes of reproduction are present in animal-like protists namely: binary/longitudinal fission, conjugation and fragmentation. Animal muticellularity also evolved in one of these groups exemplified by the choanoflagellate.

5. Movement is key to Identification THERE IS NO PROTOZOAN THAT IS NOT MOTILE!!!!!

6. PROTOZOAN VS METAZOAN Proto- first; Zoa- animal Meta – after; zoa- animal

7. Keywords Ciliophora anal pore choanoflagellate Cilliate food vacuole sarcodina Cilium/cilia contractile vacuole pseudopod Paramecium Zoomastigina amoeba Trichocyst flagellum/flagella vector Macronucleus flagellate host Micronucleus sporozoa conjugation Gullet pellicle binary fission

8. Phylogeny Most recent ancestral stock of members of Animal Kingdom Genetic make-up is not the basis What characteristic was used?

11. Protozoa No cell wall Have one motile stage Mostly ingest food Unicellular Niche is limited At least 10000 species are symbionts

13. Locomotion

14. Cilia and Flagella Axoneme- made up of 9 external pairs surrounding an internal pair Outside the cell Kinetosome- internal part of both structures

15. Pseudopodia- an extension for movement

16. Other forms of Pseudopodia Lobopodia- large and blunt extensions Filopodia- thin and usually branching Reticulopodia- forms a net-like mesh Axopodia- long and thin, supported by axial rods of microtubule Homework: what are the different classifications of Sarcodines? Give examples.

17. Nutrition-Phagocytosis vs Pinocytosis Holozoic feeders, or phagotrophs , ingest particles of food. Food vacuole – the membrane-bound vesicle containing the food. Food vacuoles fuse with lysosomes containing digestive enzymes.

18. Nutrition Often, the site of phagocytosis is a definite mouth structure, the cytostome .

19. Nutrition Saprozoic feeding (ingestion of soluble food) may be by pinocytosis or by transport of solutes across the cell membrane.

20. Excretion and Osmoregulation Contractile vacuoles function in osmoregulation and excretion More common in freshwater

21. Trichocyst Organelle in ciliates and dinoflagellates that releases a filamentous and netlike protein to trap food

22. Reproduction Fission is the cell multiplication process in protozoa. Binary fission – one individual splits into two equal sized individuals. Budding – progeny cell much smaller than parent. Multiple fission – multiple nuclear divisions followed by multiple cytoplasmic divisions producing several offspring.

23. Reproduction All of above accompanied by some form of mitosis. Mitosis in protozoa divisions varies from metazoan mitosis. Nuclear membrane often persists. Spindle may form within the nuclear membrane. Centrioles not observed in ciliates. Macronucleus of ciliates elongates, constricts, and divides without mitosis (amitosis).

24. Reproduction Many types of protists reproduce sexually as well as asexually. Isogametes – all look alike. Anisogametes – two different types. Syngamy – gametes from two individuals fuse to form the zygote. Autogamy – gametes from one individual fuse. Conjugation – gametic nuclei are exchanged.

25. Cysts Many protists are able to survive harsh conditions through the formation of cysts , dormant forms with resistant outer coverings and a shutdown of metabolism.

26. Major Protozoan Taxa After the eukaryotic cell evolved, diversification followed, resulting in many clades. Opisthokonta is a very large clade characterized by a combination of flattened mitochondrial cristae and one posterior flagellum on flagellated cells. Includes animals, fungi, chaonoflagellates and microsporidians.

27. Stramenopila The clade Stramenopila includes several groups of heterotrophs as well as certain groups of algae. Most stramenopiles have a “hairy” flagellum paired with a “smooth” flagellum.

28. Stramenopila Water molds, diatoms, golden algae, brown algae.

29. Euglenozoa Phylum Euglenozoa is a diverse clade that includes predatory heterotrophs, photosynthetic autotrophs, and pathogenic parasites. Kinetoplastids & Euglenids. Persistence of nucleoli during mitosis. Cell membrane contains microtubules to stiffen it into a pellicle .

30. Euglenids Euglenids have one or two flagella that emerge from a pocket at one end of the cell. Contain chloroplasts surrounded by a double membrane – may have arisen by secondary endosymbiosis.

31. Kinetoplastids Kinetoplastids have a single, large mitochondrion that contains an organized mass of DNA called a kinetoplast. Include free-living consumers of bacteria in freshwater, marine, and moist terrestrial ecosystems. Others are parasitic. Trypanosoma

32. Diplomonads Diplomonads : Are adapted to anaerobic environments. Lack plastids. Lack mitochondria but may have mitochondrial genes in the nucleus. Diplomonads have two nuclei and multiple flagella. Giardia

33. Retortamonads Phylum Retortamonada includes commensal and parasitic unicells. Lack mitochondria & Golgi

34. Alveolata Members of the clade Alveolata have membrane-bounded sacs (alveoli) just under the plasma membrane. Dinoflagellates, apicomplexans, ciliates.

35. Alveolata - Ciliates Members of the phylum Ciliophora use cilia to move and feed. Ciliates have large macronuclei and small micronuclei.

36. Alveolata - Ciliates Ciliates are a large, varied group of protists.

37. Alveolata - Ciliates Ciliates are structurally complex. All ciliates have a kinety system made up of the cilia, kinetosomes and other fibrils. Many have structures that can be expelled such as trichocysts and toxicysts . Defensive function

38. Alveolata – Types of Ciliates Suctorians – ciliates that lose cilia as adults, grow a stalk and become sessile. Use tubelike tentacles for feeding. Symbiotic ciliates – some commensal, others parasitic. Free-living ciliates – may be swimmers, or sessile. Stentor , Vorticella , Paramecium

39. Alveolata – Reproduction in Paramecium Paramecium , as well as many other protists, reproduce asexually by binary fission .

40. Alveolata – Reproduction in Paramecium Conjugation is a sexual process that produces genetic variation. Conjugation is separate from reproduction which generally occurs by binary fission.

41. Alveolata – Dinoflagellates Phylum Dinoflagellata is a diverse group of aquatic photoautotrophs and heterotrophs. Abundant in both marine and freshwater phytoplankton.

42. Alveolata – Dinoflagellates Each has a characteristic shape that in many species is reinforced by internal plates of cellulose. Two flagella make them spin as they move through the water.

43. Alveolata – Dinoflagellates Rapid growth of some dinoflagellates is responsible for causing “red tides,” which can be toxic to humans. California Noctiluca Bloom http://www.whoi.edu/redtide/index.html

44. Alveolata – Dinoflagellates Some dinoflagellates are bioluminescent. Others live symbiotically with corals (zooxanthellae).

45. Alveolata – Apicomplexans Apicomplexans are parasites of animals and some cause serious human diseases. Named because one end, the apex, contains a complex of organelles specialized for penetrating host cells and tissues. Have a non-photosynthetic plastid, the apicoplast .

46. Alveolata – Apicomplexans Most apicomplexans have intricate life cycles w ith both sexual and asexual stages that often require two or more different host species for completion.

47. Parabasalids Parabasalids move by means of flagella and an undulating part of the plasma membrane. This clade may have diverged from the main eukaryotic clade very early. Trichomonas

48. Amebas Amebas are found in fresh and salt water as well as moist soil. An ameba feeds by wrapping a pseudopod around its food – phagocytosis.

49. Nonactinopod Amebas Nonactinopod amebas include amebas that form lobopodia, filipodia or rhizopodia. Mostly heterotrophic and actively seek and consume bacteria and other protists.

50. Entamoebas Entamoebas are parasites of vertebrates and some invertebrates. Entamoeba histolytica causes amebic dysentery in humans.

51. Granuloreticulosa This clade has slender pseudopodia that extend through openings in the test , then branch and run together forming a net. Foraminiferans , or forams are named for their porous, generally multichambered shells, called tests.

52. Granuloreticulosa Pseudopodia extend through the pores in the test. Foram tests in marine sediments form an extensive fossil record.

53. Actinopod Amebas Actinopod amebas form a polyphyletic group. Radiolarians are one type of actinopod ameba. They have very diverse and beautiful forms.

54. Actinopod Amebas The pseudopodia of radiolarians, known as axopodia radiate from the central body.

55. Phylogeny and Adaptive Diversification Phylum Chlorophyta Phylum Retortamonada Class Diplomonadea Order Diplomonadida Phylum Axostylata Class Parabasalea Order Trichomonadida Phylum Euglenozoa Subphylum Euglenida Class Euglenoidea Subphylum Kinetoplasta Class Trypanosomatidea Phylum Apicomplexa Class Gregarinea Class Coccidea Phylum Ciliophora Phylum Dinoflagellata Amebas Rhizopodans Granuloreticulosans Actinopodans

56. Choanoflagellate Collared flagellates One apical flagellum surrounded by 30-40 microvilli Closest relative of animals Mitochondrial genome suggests that choanoflagellates are an outgroup of metazoans

57. Choanocyte of sponges