Kingdom: PROTISTA PROTOZOANS 3/7/2006 1
Kingdom: PROTISTA Single celled (unicellular), colonial or multicellular organisms Reproduce sexually or asexually Three major categories: Protozoans - first animals Algae plant-like Molds fungus-like 3/7/2006 2
CHARACTERISTICS OF UNICELLULAR ORGAISMS: BACTERIA KINGDOMS: Eubacteria & Archaebacteria CHARACTERISTICS: Cell Wall No Nucleus Tiny in size Many cause disease Reproduction binary fission Limited locomotion (movement) Classification based on shape PROTOZOANS KINGDOM: Protista Characteristics: No cell wall Nucleus present Larger than bacteria Can cause disease Reproduction: Binary fission Conjugation Spores Specialized Locomotion Classification based on locomotion Sarcodines (pseudopod) Cilliates(cilia or little hairs) Flagellates (flagella) Sporozoans (spores) 3/7/2006 3
Four Major Groups of Protozoans pseudopod Amoeba 1. Sacrodines Move by means of pseudopod ( false foot ) Some have shell-like coverings Example: Foraminiferons chambered outer shell made of calcium carbonate (limestone) Classic example: Amoeba» Typical sacrodine» Blob-like body form» Moves and feeds by pseudopod 3/7/2006 4
Four Major Groups of Protozoans Cont ( Sacrodines Cont ) Amoeba feeding: Pseudopod traps food particle Food vacuole engulfs and releases digestive chemicals Digestive food is used and waste particles (including CO2) are eliminated through the cell membrane Oxygen is absorbed through the cell membrane Excess water is eliminated through the Contractile Vacuole 3/7/2006 5
( Sacrodines Cont ) Amoeba Reproduction: Binaryfission parent cell divides into two identical cells Amoeba also respond to changes in environment: Light sensitive Various chemical responses 3/7/2006 6
Ciliates Paramecium 2.Ciliates Classic example: Paramecium Typical ciliate structure Covered with hair-like projections called cilia Cilia can be specialized for feeding and locomotion 3/7/2006 7
(Ciliates cont ) Paramecium anatomy: Pellicle hard covering on outer surface ( slipper shape) Oral groove indentation that cilia sweep food towards; Leads to gullet Gullet funnel shape structure leading to food vacuole Food vacuole moves through organism distributing food particles 3/7/2006 8
(Ciliates cont ) Two nuclei Micronucleus: small nucleus that controls reproduction Macronucleus: larger nucleus that controls other cell functions 3/7/2006 9
(Ciliates cont ) Reproduction: Binary fission (splitting in two) Conjugation (sharing of genetic material) Two paramecium line up and join together Macronuclei disappear;micronuclei divide in two One micronuclei from each pair pass through tube joining paramecium together Paramecium separate and new micro and macro nuclei form 3/7/2006 10
3.Flagellates Flagellates Move by means of flagella ( whip-like structure) Flagella move organism through watery environment in which they live Unicellular (one cell) and colonial (clusters of cells) 3/7/2006 11
(Flagellates cont ) Three main groups of flagellates: Daughter colony Individuals 1. AUTOTROPHIC: Contain chlorophyll and are therefore able to make there own food Classic example: Volvox (also forms colonies) Volvox 3/7/2006 12
(Flagellates cont ) Three main groups of flagellates cont : Trypanosoma ssp. 2.HETEROTROPHS: Can t make own food No chloroplasts Usually parasites Example: Trypanosoma ssp. Causes African sleeping sickness 3/7/2006 13
Pellicle chloroplasts Four Major Groups of Protozoans Cont. (Flagellates cont ) Three main groups of flagellates: Euglena eyespot flagella nucleus Paramylon body 3. Autotrophic and Heterotrophic: Classic example: Euglena Tiny oval shaped One pointed end and one round end Rounded end with flagellum and eyespot (reddish light sensitive structure) Moves towards light to capture energy to make own food (contain chloroplasts) 3/7/2006 14
(Flagellates cont ) Three main groups of flagellates cont : Reproduction: Binary fission (the long way) Results in mirror images or symmetrical offspring 3/7/2006 15
4. Sporozoans Complicated life cycles with spores produce at some stage: Spores: Contain hereditary material and a small amount of cytoplasm Can develop directly into mature Sporozoans 3/7/2006 16
Sporozoans cont Classic example: Plasmodium: Causes Malaria an infection of the bloodstream (destroys blood cells) common in tropical climates and spread by the Anopheles mosquito Mosquito acts as a VECTOR (carries malaria Sporozoans in its saliva from person to person) Can be treated with quinine 3/7/2006 17