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THE PROTOZOA. UNICELLULAR - EUCARYOTIC MICROORGANISMS FOUND IN THE KINGDOM PROTISTA NO COMMON BASIC STRUCTURE, SIZE OR SHAPE SIZE VARIES GREATLY - 2 TO 5,000 MICROMETERS DISTRIBUTION FREE LIVING FORMS. I. Protozoan Characteristics (65,000, 12 are extinct) Environment Found In Ocean
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THE PROTOZOA UNICELLULAR - EUCARYOTIC MICROORGANISMS FOUND IN THE KINGDOM PROTISTA NO COMMON BASIC STRUCTURE, SIZE OR SHAPE SIZE VARIES GREATLY - 2 TO 5,000 MICROMETERS DISTRIBUTION FREE LIVING FORMS
I. Protozoan Characteristics (65,000, 12 are extinct) • Environment Found In • Ocean • Zooplankton (primary energy source in aquatic eco.) • Vegetation • Rivers • Ponds • Soil • Bodies of other organisms • Found: in cells, tissue and blood stream of Host • Cause: malaria, amebic dysentery, giardiasis
B. Heterotrophic • Ingest small molecules or cells • a. Food Vacuoles - break food down
C. Reproduction 1. Asexual , a. Binary Fission -2 identical individuals b. Multiple Fission - more than 2 indenticals indo 2. Sexual a. Conjugation -, exchange genetic material
D. Classification - according to how they move or not 1. FivePhyla/Plus Euglenophyta • Sarodina , move by psuedopods (false feet) • Ciliophora - move by cilia (eyelash like) • Zoomastigina - move by flagella (whiplike) • Sporozoa - none motile • Euglenophyta - flagella (both plant/animal
Adaptations- for monitoring envirionment • Eyespot- • Detect quantity and quality of light • Cyst- (means sac in Greek) • Crate hardened covering (Lack of food, H2O, O2) • Metabolic activity stops • Important for Protozoans between hosts • Conditions Good- Protozoan emerges, resumes metabolic activity
Evolution: • First Prokaryotes: 3.5 bya • First Eukaryotic: 1.5 bya a. Endosymbiosis: one prokaryote lives inside another until both become dependent on each other (first eukaryotes)
II. Phylum Sarcodina- 40,000 Species are Amoebas • Environment • fresh/salt water • Soil a. Pelomyxa carlinensis (mud, rock, slow moving streams, ponds)
Structures • Psuedopodia- movement/feeding • Endoplasm- inner cytoplasm (thin consistency) • Ectoplasm- outer cytoplasm (thick consistency) (Fig. 26-4) • Amoeboid movement- Cytoplasmic • Endocytosis- engulfing • Phagocytosis- feeding • Pinocytosis- dinking • Contractile Vacuole- pumps out excess water
Ecological Role • Foraminifera- Shell (test) med of calcium carbonate • Created limestone/chalk deposits • Found in White Cliffs of Dover/ Pyramids
Radioalarians- Shell (test) made of silicon dioxide • Created Chert and Jasper (rock)
D. Human Diseases (non-free living amoebas) Entamoeba histolytica Enters from contaminated water, food Lives in large intestine (enzymes attack lining causing ulcers) Causes: Amoebic Dysentery diarrhea dehyd, bloody stool, death ACANTHAMOEBA Sp. Causes: 1. Granulomatous Amoebic Encephalitis 2. Keratitis
Environment • Ponds(Marine/Fresh) • Slow moving streams Monodinium spp. Stentor Euplotes http://ucf.tekkom.net/bsc2011/?sort=class&lab_number=1
Food Source • Bacteria • Algae Vorticella Stentor
Internal Structure • Pellicle • Surrounds cell membrand • Made of protein (clear and elastic) • Gives shape • Oral groove (lined with cilia) • Creates currents to sweep food to Mouth Pore • Mouth Pore open to Gullet • Gullet forms Vacuoles • Vacuoles circulate food to cytoplasm • Anal Pore- undigested food passes out
Macronucleus a. Controls Metabolic/ Developmental Activities • Micronucleus • Controls reproduction (conjugation) 8. Cilia- External Cytoplasm-movement
Reproduction • Asexual • Binary Fission (Macro-splits) • (Micro- divides mitotically)
Sexual- conjugation • Macro- disintegrates • (p515) Micro-nuc-Meiosis occurs (2n) • 4 Haploid Micro-Nuclei produced • All but 1 micor nucli disintegrate in each Paramecium • Remaining Micro-nuc divide by mitosis (n) • 2 Paramecium exchange (n) micro nuc./ fusing forming 2n micro-nuc • Cells separate/ new macro forms • Following conjugation/ paramecium divide producing 4 identical paramecium (different from original 2)
IV. Phylum Zoomastigina- 2500 species • Environment • Ponds • Lakes Peranema Giardia
Movement- flagella 1. Hairlike structure made of microtubules
Human Diseases Zooflagulates (parasitic) • Trypanosoma (Genus) • Found in blood fish, amphibians, reptiles, birds, mammals • Spread by blood sucking insects from Host to Host
Kinds of Zooflagellates • T. trypanosomiasis (African Sleeping Sickness) • Transmitted by the Tse Tse fly • Causes lethargy, mental deterioration, coma
b. T. cruzi (Chaga’s disease) • Transmitted by “kissing bug” • People suffer fever/ heart disease
c. Leish mania donovani • Sandflies • Blood disease (p516) • Africa, Asia, Latin America • Fatal
d. Giardia lamblia • Transmitted by feces in water • Causes diarrhea/cramps
Treatment for protozoan infections is usually an antibiotic called metranidazole also called flagyl.
Characteristics • No locomotion • Parasitic • Complex life cycles • Spore encased in protective coat
5. Live in the host blood/tissues • Example: Toxoplasma gondii- found in birds, rodents, cats. In Human it causes toxoplasmosis- which can cause birth defects in newborns
SPOROZOA ALL OBLIGATE INTRACELLULAR PARASITES ALL HAVE COMPLEX LIFE CYCLES PATHOGENIC SPOROZOAN-PLASMODIUMSp. CAUSATIVE AGENT OF MALARIA FOUR SPECIES CAUSE MALARIA
1. P. MALARIAE 2. P. OVALE 3. P. VIVAX 4. P. FALCIPARUM LIFE CYCLE OCCURS IN TWO ORGANISMS MOSQUITO (ANOPHELES Sp.) AND ANIMAL BODY SEXUAL CYCLE IN MOSQUITO ASEXUAL CYCLE IN HUMAN BODY
3 IMPORTANT STAGES IN LIFE CYCLE SPOROZOITE MEROZOITE GAMETOCYTE LIFE CYCLE OF PLASMODIUM
TOXOPLASMOSIS • CAUSED BY TOXOPLASMA GONDII • SEEN MOSTLY IN PEOPLE WITH COMPROMISED IMMUNE SYSTEMS • CATS ARE AN ESSENTIAL PART OF THE LIFE CYCLE OF THIS PROTOZOAN • THE ORGANISM REPLICATES IN THE INTESTINE OF THE CAT. • IT PASSES OUT OF THE CAT IN ITS FECAL MATERIA • PEOPLE INJEST THE ORGANISM
Plasodium • Causes Malaria (victim die: anemia, kidney failure, brain damage) • Cause more deaths than any other genus in history • 500 million people a year infected • 2.7 million die a year
Life cycle • Bitten by – anopheles (female mosquito) • P. sporozitesenter blood to live cells • Merozoites emerge to infect RBC where they reproduce asexually • RBC burst, releasing toxins (must kill both blood and liver merozoites) • Merozoites form Gametacytes • Anopheles bites, injests Gametocytes • Sperm-egg form zygote • Zygote burst releasing sporozoites to salivary glands/cycle repeats • Cure- derived from cinchona tree (quinine) 500 years