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Home , Accessory pigment, Domain (biology), Protist

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Domain Eukarya- The Most taxonomist now recognize the as the largest . The three taxa at the domain level are the , Archae, and Eukarya. All eukaryotes are in the domain Eukarya. Within those domains are super groups. The king- doms are found within the super groups. Of the five king- doms three have survived-Animalia, Plantae, and Fungi. The Monerean and Protista kingdoms are no longer recognized.

The major difference between prokaryotic and eukaryotic cells, is the existence of membrane bound . These organelles include the nucleus, E.R., lysosome, , and . The advantage of having compartmentalization allows for specialization of tasks and greater efficiency. The of the organelles involves two different processes- involution of membranes to form the cytomembrane (endomembrane) system and endosymbiosis. Shown is the possible outline of sequence of events that led to the cytomembrane system which led to the develop-ment of the nucleus, E.R., Golgi apparatus, lysosome, vacoules and vesicles. The origination of the mitochondrion is thought to have come about by a prokaryotic cell engulfing another aerobic heterotrophic . This cell took up residence and eventually became the mitochondrion. Evidence for this includes that the mitochondrion like prokaryotic cells have circular, nonhistone DNA. The mitochondrion has prokaryotic-like ribosomes and does proteins synthesis like a prokaryotic cell. The mitochondrion replicates doing binary like a prokaryotic cell. The origination of (, and leukoplasts) thought to have come about by a prokaryotic cell engulfing another photosynthetic, aerobic prokaryote. This cell took up residence and eventually became the chlroroplast. Evidence for this includes that the plastids like prokaryotic cells have circular, non-histone DNA. The plastid has prokaryotic- like ribosomes and does proteins synthesis like a prokaryotic cell. The plastid replicates doing binary fission like a prokaryotic cell. In the course of evolution this has happened many . The that were involved in a secondary endosymbiosis have 3-4 membranes on their chloroplasts.

 All have a nucleus and are therefore eukaryotic.

 Protists are either -like, -like or -like.

1)PROTOZOANS Animal-like protists Notes 3 * unicellular * live in H2O * * microscopic * 4 phyla classified by locomotion (how they move)

Amoebas: Sporozoans: Group shapeless parasitic protists Rhizopoda Zoomastigina Ciliophora Sporozoa 8,000 kinds of = Flagella whip Cilia covers body No movement Locomotion cytoplasm- from side to immobile containing side extensions; change shape Example Trypanosome (get (freshwater by fly bite) *Contractile All are parasites. and salt One that in to get water) guts rid of excess water Type of Asexual Binary fission Binary fission & = reproduction Conjugation reproductive by binary cell that forms fission without fertilization Diseases? African sleeping sickness The Prostista no longer exists. Protists though are considered to be unicellular (or multicellular without differentiation). In other words any not considered to be a plant, animal or fungus is a protist. Remember, protists, , fungi, and are all in the same domain, Eukarya. There are five recog- nized super groups in the domain Eukarya 1. 2. 3. 4. (plant kingdom found in this group) 5. Unikonta (Animal and Fungi Kingdom found in this group) All the tan boxes represent groups that used to be in the Protista Kingdom. The super group Excavata (relationship in the Eukarya is not clear) a. Grove on one side of the cell body b. and have reduced mitochondria c. Euglenozoans have flagella with unique spiral rod i. Kinetoplastids-have large mitochondrion with large mass of DNA-feed on ii. -some in do in the dark become heterotrophic. Have protein pellicle under the .

Giradia intestinalis (shown) can cause intestinal distress and diarrhea. vaginalis is a sexually transmitted parasite that can infect both males and females causing damage. Has the ability to change surface proteins to evade recognition by the . (tricky little suckers!) The tsetse fly – sleeping sickness

The super group- Chromalveolata I. Alvelolates-have membrane bags under cell membrane A. -cellulose plates with perpendicular grooves with flagella. Cause of red . Some , heterotrophs and mixotrophs. B. Apicomplexan-parasites (Plasmodium) causes malaria. Complex cycle C. Ciliates-Covered with cilia () has large and small nuclei II. -covered with numerous fine “hairy”flagella which is paired with regular shorter Dinoflagellates: The Spinning Ones

Spin around using two flagella Responsible for Red Create toxins that can kill animals and sometimes people

The life cycle of Plasmodium, the cause of malaria Cilliates to include stentor and parmecium

Dinoflagellate causes red tide

Sexual reproduction

Asexual reproduction

 Binary  fission II. Stramenopiles-covered with numerous fine “hairy”flagella which is paired with regular shorter flagellum. Stores in form of laminarin (polysaccharide) and oil. A. -cell walls of silicon dioxide (glass) that overlap Petri dish. Very strong . Over 100,000 . B. have yellow and brown caroteinoids. Most unicellular, some mixotrophs. C. -Most complex of all the algae. Somewhat like plants (analogous structures) beds Used for food in some countries. DIATOMS

The brown algae exhibits the life cycle like plants- alternation of generations. D. (water ) was once classified as fungus because of hyphae (long strings of cells) but case of . Has cell walls of cellulose not chitin. No longer has plastid and are decomposers. Cause of potato blite in 19th century. Decomposer. ` The super group- Rhizaria Many members have long, stringy pseudopods (fake extension) A. Forams (foraminerferans) have shells made of calcium carbonate. Pseudopods extend through the pores. B. Radolarians internal of silica with pseudopods extending out.

Globerigerina-radolarian

Radolarian The super group- Archaeplastida Contains , and Plant Kingdom A. Red algae-contain photosynthetic accessory , A and . Makes the algae appear red-green to red depending on the amount. Phycoerythrin absorbs blue and green light so red algae can survive in deeper water that blue and green light penetrates. Mostly multicellular and has alternation of generation life cycle with no flagellated . B. Green algae-contain and B like higher plants 1. Chlorophytes unicellular, colonial and multicellular species. Reproduction includes alternation of generations.

Example of red algae to the left and green algae above Chlamydomonas are actually unicellular and flagellated. A is a hollow boll composed of hundreds of flagellated cells in a single layer. Life cycle of chlamydonas-single celled green algae 2. Charophytes rosette shaped cellulose synthesizing complexes, and other characteristics in common with higher plants. Closest relative to land plants. Super group Unikonta-two major Amoebozoans and . Include slime molds, amoebas, fungi and animals. I. Amoebozoans- A. Gymnamoebas- amoebas with club-like pseudopods. Heterotrophs consuming prokaryotes and other protists B. Entamoebas- parasitic amoebas. Entaboeba histoytica causes dysentery. C. Slime molds- Two types Plasmodial slime molds form acelluar masses where as cellular slime molds form cellular plasmodial masses. Can live as individual cells

II. Opisthokonts-Includes nucleariids, fungi, and animal. A. Nucleariids are -like protists and more closely related to fungi than other protists B. Kingdom Fungi that are absorptive heterotrophs. Characterized by columns of cells called hyphae. Most are multicellular. C. Choanoflagellates are flagellated protists that will form colonies. Individuals look much like cells. D. Kingdom Animalia are multicellular ingestive heterotrophic .

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