Nucleus – contains DNA. Mitochondria – organelle used in energy production. Golgi – part of the secretory system of the ER. Plastids – organelles containing photosynthetic pigments. Extrusomes – organelles that extrude something from the cell. Pseudopodia Flagella Cilia Nonmotile
Fig. 11.4 Pseudopodia are extensions of the cell cytoplasm used for locomotion.
fill with fluid and then expel the fluid outside the cell. Function in osmoregulation. More common in freshwater species. Ammonia is the form they excrete nitrogen waste. Regulate through ACTIVE TRANSPORT!
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.
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.
Members of the phylum Ciliophora use cilia to move and feed. Ciliates have large macronuclei and small micronuclei. Ciliates are a large, varied group of protists.
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
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
Phylum Dinoflagellata is a diverse group of aquatic photoautotrophs and heterotrophs. Abundant in both marine and freshwater phytoplankton.
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. Two flagella Transverse Longitudinal Some photosynthetic Some heterotrophic Some have cell wall made of plates Red tide neurotoxin
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 Some dinoflagellates are bioluminescent. Others live symbiotically with corals (zooxanthellae).
Photosynthetic dinoflagellates (brown) Live in corals Provide nutrients for coral by photosynthesis Mutualism
Stages of Infection Early - fever, weakness, headache, joint pains. Intermediate - anemia, cardiovascular, endocrine & kidney disorders. Late - CNS involvement, indifference to environment, unpredictable mood changes, coma and death.
Origin of Protozoa <ul><li>Earth is 4.6 billion years old </li></ul><ul><li>Prokaryotic cells date back over 3.5 billion years </li></ul><ul><li>1.5 Billion years ago </li></ul><ul><ul><li>Eukaryotic cells </li></ul></ul><ul><ul><ul><li>Became protozoans </li></ul></ul></ul>
Nutrition in Protozoans <ul><li>Autotrophs </li></ul><ul><li>Heterotrophs </li></ul><ul><ul><li>Phagocytosis </li></ul></ul><ul><li>Mixotrophs </li></ul>
Phylum Retortamonada Class Diplomonadea <ul><li>Giardia lamblia </li></ul><ul><ul><li>Giardiasis </li></ul></ul><ul><ul><ul><li>Backpackers disease </li></ul></ul></ul><ul><ul><ul><li>Beaver fever </li></ul></ul></ul><ul><li>Inhabits intestines of several animals and man </li></ul><ul><li>Acquired by drinking water with cysts </li></ul><ul><li>Cramping and diarrhea </li></ul>
African Sleeping Sickness <ul><li>Parasite - Trypanosoma </li></ul><ul><li>Chronic disease lasting years. </li></ul><ul><li>Affecting countries of western & central Africa. </li></ul><ul><li>Vector - Tsetse fly ( Glossina ) </li></ul><ul><li>Reservoirs - infected wild animals and humans </li></ul>
Plasmodium <ul><li>Malaria </li></ul><ul><li>Most important parasitic disease of humans today </li></ul><ul><li>WHO estimates that 270 million new cases occur annually with 2 million annual deaths </li></ul><ul><li>Transmitted by bite of infected mosquitoes of genus Anopheles </li></ul>