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Eukarya is now divided into 4 supergroups, , SAR , and Unikonta. It replaces the earlier 5- classification of – all , Protista – early and 3 multicellular kingdoms , Fungi and . Kingdom monera is replaced by 2 new domains and . The classification of Eukarya is going on. Molecular data has broken the boundaries between protista and 3 multicellular kingdoms. Eukarya is likely to get more than 20 kingdoms but none of them is protista. : of past are separated into 7 new groups that also have plants, fungi and animals. 1. Excavata 2. 3. Alveolata 4. 5. Archaeplastida, also has plants 6. Ameobozoans 7. , also has fungi and animals Protists were first eukaryotes to evolve. Protists include unicellular eukaryotes and their simple multicellular relatives. The latter are filamentous or colonial. , and sexual arose for the first time in this kingdom. All the of plants, fungi and animals arose in this kingdom. Protists also possess many unique organelles not found anywhere else in the 3 domains. Like the 3 higher kingdoms the Protists are photosynthetic (like plants) or heterotrophic absorptive (like fungi) or heterotrophic Ingestive (like animals). Excavata: is a clade, some have excavated groove on side of body, reduced or modified mitochondria and unique flagella. include , and Eugleonozoans (kinetoplastids and euglenoids). a) Diplomonads: reduced mitochondria, called which cannot use , therefore, diplomonads are anaerobic. intestinalis in intestines of . It has 2 similar nuclei and several flagella. It causes abdominal cramps and diarrhea in humans. b) Parabaslids have reduced mitochondria called and produce some ATP anaerobically and generate . vaginalis causes sexually transmitted infections of vagina and urethra in males. c) Euglenozoans are a diverse clade having , and parasites. All have a spiral or crystal rod of unknown function in flagella. a. Kinetoplastids have a single with organized DNA mass called . cause sleeping sickness, fatal if untreated. bites and spreads the sleeping sickness in Africa. Trypanosoma has undulating membrane to locomote in thicker plasma. b. Euglenoids has a pocket at one end and 1or 2 flagella emerge from it. Flagella have a crystalline rod besides 9+2 found in all eukaryotic flagella. has eyespot to shield photodetector present on long . It enables Euglena to swim towards source of light. Pellicle covers the body. It has strips below membrane. Besides swimming, Euglena can glide by changing its shape. Mixotrophic Nutrition: Euglena has several covered with 3 membranes but can be heterotrophic and absorb organic from surroundings. Euglena divides by longitudinal and lacks . Stramenopiles have , golden , and . Most have one long hairy and one short smooth flagellum. d) Diatoms (100,000 species) are most abundant unicellular forms in . The body is covered with an intricately designed 2-half silica shell. Adults are Diploid and lack cilia or flagella. Main reproduction is by binary fission. Sexual reproduction is by flagellated . The remains of shells produce mined for filtering and abrasive materials. It acts as Biological Pump to move CO2 from air to floor. Diatoms are most important producers in biosphere. e) have and brown and all cells have 2 flagella at one end. Most golden algae are autotrophs but some are mixotrophic. Most golden algae are in marine or fresh . is a a colonial golden alga of . f) Brown Algae - are usually the large sea weeds called . In addition to Chl a, these have a brown . Coastal areas have and Sea palm () lives off west coast of Canada and Unites States. Body has like holdfast, stem like stipe and like blades. Blades bear sporangia. Cells in sporangia undergo meiosis and form with 2 flagella. Zoospores germinate to form multicellular male and female . Male gametophytes produce also with 2 flagella. Female gametophytes develop eggs. Fertilization of egg and forms which divides to form the . Alternation of generations involves a dominant diploid sporophyte generation and multicellular haploid generation. Algin a gelatinous material added to ice creams and cream cheese is extracted from brown algae. g) Oomyces include water molds, white rusts and the downy mildews. These have cell walls of . These have like septate hyphae. by flagellated zoospores and sexual reproduction involves flagellated sperms. Phytophthora infestans causes potato late blight and was responsible for Irish Famine in 19th century killing a million people. h) Alveoates: have membrane bound sacs below . i) – Pyrrophyta are unicellular covered with cellulose plates. They have 2 flagella placed at right angle to each other. These are important in oceans. They are also responsible for causing Red Tides, example . The is caused due to sudden growth due to availability of Nitrogen or Phosphorus brought by rivers. Apicomplexans are unicellular parasites of animals and include causing species. No flagella present. All have apical complex at one end of cell to penetrate host cells. . It is transmitted by females of , species. Malarial parasite completes sexual phase in Anopheles and asexual reproduction in human liver and red blood cells. Sporozoites, asexual stages of malarial parasite attack liver cells and later erythrocytes and brain cells. Malaria kills 2 million deaths per out of 300 million affected each year. j) have cilia and covered with pellicle. Common example is species. It has a Meganucleus and a . They have 2 contractile surrounded by feeding canals to expel excess water entered due to endosmosis. Oral groove guides like bacteria and form a food . Food vacuoles stream in a circular path inside the body. Lysosomes join and help to digest food. These reproduce asexually by transverse . Sexual rep is by Conjugation for which 2 paramecia join temporarily and exchange nuclei and separate. 2 nuclei from different paramecia fuse to result in fertilization. k) Rhizarians include a diverse group of unicellular with thread like . l) Forams: are having body covered with porous shells called tests with many chambers outside cell membrane. Forams are unicellular heterotrophs and some may grow to several centimeters. Forams form sediments and have been discovered from . . m) Radiolarians are unicellular and have internal delicate form of silica. Pseudopodia radiate from the central body. Archaeplastida are autotrophs and include , and land plants. Plastids in red and green algae arose by primary endosymbiosis by engulfing a cyanobacterium. n) Red Algae - These are mainly filamentous or leafy. Besides a, these have red and to give various colors. Red algae are delicate sea weeds. Red algae are important sources of gelling agents and Carageenan. is edible red alga used as a -wrap. Green Algae include Chlorophytes and Charophytes. These are most common in fresh water. These have and b, store food as and have cellulose in cell walls. All characteristics are common with plants. Asexual reproduction can be by flagellated called zoospores or spores without flagella. Sexual reproduction is by flagellated gametes. Many algae, like plants, form a non-flagellated egg and a flagellated sperm. This sexual reproduction is called . Algae lack multicellular sex organs.They have various forms: unicellular-; filamentous-; leafy - Ulva or colonial - with daughter colonies inside. Land plants originated from charophytes.

o) Slime Molds are naked protists which feed by . Plasmodial Slime Molds have protoplasmic masses called plasmodium. These reproduce asexually by spores formed in walled sporangia in a cluster called fruiting body. Spores develop into amoeboid or flagellated gametes. Common example is species. Cellular Slime Molds live as solitary amoeboid cells. Under unfavorable conditions these can form aggregations called pseudoplasmodium. When favorable conditions return sporangia in a fruiting body produce spores. The spores give rise to single cells to complete the cycle. p) Tubulinids form tube like pseudopodia and are covered with cell membrane. They change, all the time, their body-shape. They feed by phagocytosis. Freshwater forms have contractile vacuoles to expel excess water. Common example is proteus. q) Entamoebas include 6 species living in humans and E. histolytica causes amoebic -blood in stools. Opisthokonts have posterior flagella. These include Nucleariids, fungi, and animals r) Nucleariids are closest to fungi. s) Choanoflagellates are simple multicellular protists and closest line to animals. t) Animals arose from an ancestor close to choanoflagellates.