Zoology Exam 2
What are the diseases for each parasitic protist and their lifecycles?
* Trypanosoma 1. Inside the host, the trypomastigotes invade cells near the site of inoculation, where they differentiate into intracellular amastigotes 2. The amastigotes multiply by binary fission 3. Differentiate into trypomastigotes, and then are released into the circulation as bloodstream trypomastigotes 4. Trypomastigotes infect cells from a variety of tissues and transform into intracellular amastigotes in new infection sites 5. The "kissing" bug becomes infected by feeding on human or animal blood that contains circulating parasites 6. The ingested trypomastigotes transform into epimastigotes in the vector's midgut 7. The parasites multiply and differentiate in the midgut 8. Differentiate into infective metacyclic trypomastigotes in the hindgut *Plasmodium
What are the main features of supergroup Archaeplastida?
- One member of the Phylum Chlorophyta, the green algae Volvox. These protists undergo both sexual and asexual reproduction - These organisms seem very plant-like they share some features with animals - They have motile cells during reproduction and their colonial structure is reminiscent of a blastula seen during development in animals
What are the main features of supergroup Excavata?
- Presence of a flagellum and specialized mitochondria - Includes Euglenozoa, Parablastids (Parablasalida) and Diplomonads - Divided into two sub-phylums , Euglenida and Kinetoplasta (Trypanosoma - African Sleeping Sickness/Chagas Disease
Choanocytes (collar cells) how do they work, where are they located.
-By cooperatively moving their flagella, choanocytes generate a flow of water through the sponges pores, into the spongocoel, and out through the osculum. This improves both respiratory and digestive functions for the sponge, pulling in oxygen and nutrients and allowing a rapid expulsion of carbon dioxide and other -Are found in the lining the radial cavity, which empty into the spongocoel through apopyle.
Unikont
-Proposed Supergroup -Unites Amoebozoa and Opisthokonta on the grounds that when flagellated cells are present, there is only one flagellum. -Reccent phylogenies based on molecular data place the root of the eukaryote tree between the Unikonts and all other unicellular taxa, which grouped as "Dikonts"
What is endosymbiosis? Who came up with the idea? Why is it important?
-Symbiosis in which one of the symbiotic organisms lives inside the other. -Biologist Lynn Margulis first made the case for endosymbiosis -Endosymbiosis explains the origin of mitochondria and chloroplasts;It seems likely that the first eukaryotic cells gained a slight edge over their neighbors when the mitochondria, a rich source of energy, moved in with them. The mitochondria and their hosts relied more and more on each other in order to survive. Eventually, neither could succeed alone — but as a team they produced millions of descendants, establishing a whole new domain of life.
Phylum Cnidaria:
...
Phylum Porifera:
...
Protists:
....
What are some general features of Cnidarians?
1. Cnidocytes present, typically housing sting organelles called nematocysts 2. Entirely aquatic, some in freshwater, but most marine 3. Radial Symmetry 4. two types of individuals: Polyps (fingers up) and Medusae (fingers down) 5. Adult body two-layered DIPOLOBLASTIC with epidermis and gastrodermis derived from embryonic ectoderm and endoderm 6. Incomplete Gut called gastrovascular cavity which serves as the basis for the hydrostatic skeleton; often branched or divided with septa 7. Tissue Level of Organization 8. Aceolomate 9. No excretory/respiratory system 10. Muscular Contractions 11. Sensory Organs: - Ocelli - Light -Statocyst -Balance 12. No Coelomic cavity 13. Asexual reproduction by budding and sexual reproduction by gametes in the medusa and some polyps; momoecious or dioecious; holoblastic indeterminate cleavage; planula larval form 14. Nervous system- Nerve Net: Neuromuscular; no myelin sheath/axons; neurotransmitters 15. Epitheliomuscular cells: muscle/ connect to the outside of the body --> extend, contract, bend, and pulse
What are some general protists' features/characteristics?
1. Unicellular; some colonial, and some with multicellular stages in their life cycles 2. Mostly microscopic, although some are large enough to be seen with the unaided eye 3. All symmetries represented in the group; shape variable or constant (oval, spherical, or other) 4. NO GERM LAYER PRESENT 5. NO ORGANS OR TISSUES, but specialized organelles are found; nucleus single or multiple 6. Free-living, mutualism, commensalism, parasitism all represented in the groups 7. Locomotion by pseudopodia, flagella, cilia, and direct cell movements; some sessile 8. Some have a simple endoskeleton or exoskeleton, but most are naked 9. Nutrition of all types: autotrophic (manufacturing own nutrients by photosynthesis),heterotrophic (depending on other plants or animals for food), saprozoic (using nutrients dissolved in the surrounding medium) 10. Aquatic or terrestrial habitat; free-living 11. Reproduce asexually by fisson, budding, and cysts and sexually by conjugation or by syngamy (union of male and female gametes to form a zygote) 12. division of labor between cells
Metazoa
All animals together form a monophyletic grouping
Examples of supergroup Ameoba.
Amoeba
What are the 3 forms of sponges? How does water move in each?
Asconoid-are small , simple forms with a tube-shaped body; -> Ostium->Spongocoel->Osculum Synconoid-also have a tubular body whose wall is much thicker and highly folded into a series of incurrent canals that deliver water into radial canals lined with choanocytes. -> Ostium->Incurrent Canal->Prosopyle-> Radial Canal-> Spongocoel (apopyle)-> Osculum Leuconoid-the largest and most complex ones; permits for an increase in body size. ->Ostium-> Incurrent Canal-> flagellated chambers-> Excurrent canals-> Osculum
What are the main classes of P.Cindaria and key features of each? Any representative organisms/examples?
C. Hydrozoa (Obelia, Tubularia, Hydra; O. Siphonophora): - Polyp and Medusa form - Most marine and Colonial - Repro- budding - Hydrostatic skeleton - Hypostome- mouth C. Scyphozoa (Aurelia): - Polyp - Mostly marine and open ocean - Mesoglea prominent - No shelf velum - internal fertilization -> zygote -> scyphistoma -> strobilation -> forms bud -> jellfish medusa C. Cubozoa (Box Jellies): - Medusa - Box shape - Shelf velarium C. Anthoza (Metridium): - Polyp - Sea anemone and coral - All marine - Provide food and recycle P/N waste - Photosynthetic zooxanthellae - Corals and Global Warming - Increase [CO2] - More dissolved CO2 -> Decrease pH -Increase in ocean temps. No pedal disc -Rain forest of the ocean
Body forms? In which classes do you see each?
C. Hydrozoa- Polyp and Medusa C. Scyphozoa- Polyp C. Cubozoa- Medusa C. Anthoza- Polyp
How are sponges classified? What are the main classes and characteristics of each?
Kingdom Animalia (animals) Phylum Porifera (sponges) Classes: Calcarea (calcerous sponges - having spicules), Demospongiae (horn sponges, like the bath sponge), Scleropongiae (coralline or tropical reef sponges), and Hexactinellida (glass sponges).
Examples of supergroup Alveolata.
Phylum Apicomplexa - Plasmodium (Malaria)-Lifecycle Phylum Dinoflagellata - dinoflagellates Phylum Ciliophora - Paramecium, Vorticella, Stentor, Spirostomom, Didinium
Examples of supergroup Archaeplastida.
Phylum Chlorophyta - Volvox
Examples of supergroup Excavata.
Phylum Euglenozoa Subphylum Euglenida - Euglena Subphylum Kinetoplastida - Trypanosoma (African sleeping sickness
Examples of supergroup Rhizaria.
Phylum Foraminifera - formaniferans Phylum Radiolaria - radiolarians Actinosphaerium
What are Placozoans? Some features?
Placozoans are extremely simple animals. Perhaps not coincidentally, they also have the smallest amount of DNA ever measured for any type of animal. Their bodies are made up of a few thousand cells of just four types. You can compare this to sponges, which have anywhere from 10 to 20 different kinds of cells, to flies, which have roughly 90 different cell types, and to you and other mammals, which have over 200 different types of cells. Placozoans are transparent, flat, round (up to 3 millimeters across), and have two distinct sides. A tissue layer composed of two types of cells, column-shaped cylinder cells with cilia and gland cells without cilia, make up the ventral (or bottom) surface. The upper dorsal surface consists of a layer of just cover cells, which are ciliated and flattened toward the outside of the animal.
How are protists classified currently? How did scientist use to classify them? What are the main groups/supergroups we examined in class?
Protist are classified by: 1. Ecological Role - Plant-Like: (Algae) - photosyn/non-photosyn - Animal-Like: (Protozoa)- heterotrophic/ not monophyletic - Fungus-like- body form/absorptive nutrition 2. Habitat -Plankton- swimming or floating -Protozoan plankton- zooplankton 3. Motility a. Flagellates b. Ciliates c. Amoebae 4. Main Supergroups Examine: -Excavata -Rhizaria -Aveolata
How do protists move? Mechanisms and processes involved in movement (i.e. how does pseudopodia movement work versus flagella/cilia)
Protist move by way of: 1. Flagella- flagellum propels water parallel to the main axis of the flagellum ( flagellla are longer and less numerous) 2. Cilia- cilium propels water parallel to the surface to which the cilium is attached (relatively short but larger numbers) - Both cilium and flagellum contain nine pairs of longitudinal microtubules arranged in a circle around a central pair. 3. Pseudopodia- are temporary protrusions of cytoplasm that function in locomotion or ingestion. ability to form temporary cytoplasmic extensions called pseudopodia, or false feet, by means of which they move about. This type of movement, called amoeboid movement, is considered to be the most primitive form of animal locomotion.
Syncytical ciliate hypothesis vs. Colonial flagellate hypothesis (Haeckel)
SCH- Metazoa originated from a single-celled ciliate with multiple nuclei, which became compartmentalized. CFH- Metazoa originated from a colony of flagellated cells. Individual cells became differentiated for specific functions.
Sensory organs, Rhopalium, nerve net, stinging cell (what are they called and how do they work?).
SENSORY ORGANS: - Ocelli - Light -Statocyst -Balance RHOPALIUM (EYE SENSORY): are small sensory structures of Scyphozoa (typical jellyfish) and Cubozoa (box jellies). In Aurelia they lie in marginal indententions around the bell and are flanked by rhopalial lappets. NERVE NET: - Neuromuscular - No myelin sheaths/axons - Neurotransmitters - two-way STINGING CELLS -> Cnidocytes contain nematocysts: - Hair like trigger- Cnidocil - Some sticky while other sting
How do various protists reproduce(asexual, conjugation), what is there life cycle?
Sexually: - Binary Fission, which yields two essentially identical individuals. (Protozoa) - Budding, when progeny cell is considerably smaller than the parent and then grows to adult size (Occurs in ciliates) - Multiple fission (Schizogony), when several nuclear divisions precede division of the cytoplasm (cytokinesis) so that numerous individuals are produced almost simultaneously. (this is seen Apicomplexa and some amebas. When multiple fission leads to spore or sporozoite formation, called sporogony.
What new tissues? Advancements are we seeing?
TISSUE LEVEL: - Muscle Contractions -No excretory/respiratory system -Sensory Organs - Nerve Net
Major parts of a sponge (You should know important structures, especially ones from diagrams from lecture)
The body of a sponge has two outer layers separated by an acellular (having no cells) gel layer called the mesohyl (also called the mesenchyme). In the gel layer are either spicules (supportive needles made of calcium carbonate) or spongin fibers (a flexible skeletal material made from protein). Sponges have neither tissues nor organs. Different sponges form different shapes, including tubes, fans, cups, cones, blobs, barrels, and crusts. These invertebrates range in size from a few millimeters to 2 meters tall.
Parazoa
The simplest animals, sponges have no true tissue type and only possess specialized cells
````````How do protists relate to other eukaryotes?
Todays protists include groups whose ancestors were among the very last to split from the organisms that gave rise to plants, animals, and fungi.
Heterotrophic
depending on other plants or animals for food
Autotrophic
manufacturing own nutrients by photosynthesis
What are some trends in animal evolution?
o Cells - tissues - organs - organ systems o Diploblastic -troploblastic o Acoelomate - Psuedocoelomate - Coelomate o No symmetry (asymmetry) - radial symmetry - bilateral symmetry o No cephalization (head region) - cephalization o Incomplete gut (one opening) - complete gut (two openings) o No segmentation - segmentation
What are the major sponge cell types?
pinacocyte (EPIDERMIS CELLS) - pinacocytes are the thin, flattened cells of the epidermis, the sponge's outer layer of cells. porocyte - cells with pores that allow water into the sponge; they are located all over the sponge's body. choanocyte (COLLAR CELLS) - also called collar cells, choanocytes line the inner cavity of the sponge. They have a sticky, funnel-shaped collar (that collects food particles) and a flagellum (which whips around, moving water). The sponge obtains its nutrients and oxygen by processing flowing water using choanocytes. Choanocytes are also involved in sponge reproduction; they catch floating sperm. Archaeotype (AMOEBOCYTES)- Cellular differentiation is an essential function of the archaeocyte. All specialized cells within the sponge have its origins with the archaeocyte. This is especially important in reproduction as the sex cells of the sponge in sexual reproduction are formed from these amoeboid cells.
Eumetazoa
the first major split in the animal kingdom is between sponges and all other animals that possess tissues
Dikont
they have two flagella when flagella are present
Phagotrophs (holozoic feeders)
those that ingest visible particles of food.
Osmotrophs (saprozoic feeder)
using nutrients dissolved in the surrounding medium; those ingesting food in a soluble form. -
What are some general features of sponges?? What is their "skeleton" made of?
*- Sponges live all over the world, 99% of all sponges live in marine water, but some sponges made of spongin fiber live in freshwater. Sponges can be attached to surfaces anywhere as deep as 8km in the ocean on the bottom of the ocean floor. - Sponges are similar to other animals in that they are multicellular - Lack cell walls and produce sperm cells - They lack true tissues and organs - No Body Symmetry - Reproduce asexually through budding - Sponges are extremely slow-moving or sessile filter-feeders that draw water through pores and specialized filter cells to gather food - These structures are full of pores in which specialized collar cells sit, constantly drawing in water and filtering out food particles. The waste water is then pushed into a central chamber and out a large opening. - No Tissue - No Cardiovascular or nervous system - Nor do they have any muscles or sense organs *Some species of sponges produce only one type of gamete, while others produce both. Sponges release sperm into the water; there they are captured by other sponges just like food particles. However, the collar cells change when they encounter gametes, enabling them to carry the cells to their own eggs. Sponges also sometimes reproduce asexually via budding.* *- Sponges gain their structure from a skeleton of collagen with reinforcing spicules of either calcium or silicon compounds
Choanoflagellates: what are they and why are they important? Relation to sponges, Collar cells
*Are free-living, single-cell and colony forming eukaryotes ubiquitous in aquatic environments *Choanoflagellates are aquatic filter-feeders that are found all over the world in both marine and fresh water. They form an important link in the carbon cycle, consuming bacteria and algae and consumed in turn by larger zooplankton. They are also the closest known sister group to animals and there has recently been a surge of interest in them because of their promise to help us understand how animals first evolved. * Choanoflagellates are almost identical in shape and function with the choanocytes, or collar cells, of sponges; these cells generate a current that draws water and food particles through the body of a sponge, and they filter out food particles with their microvilli. Choanoflagellate-like cells are also found in other animal phyla; in organisms such as flatworms and rotifers, for instance, choanoflagellate-like cells are found in flame bulbs that act as excretory organs.
Important structures of a living Paramecium (w/picture)
*Oral Groove *Cytostome *Contractile Vacuole *Macro/micronucleus *Food Vacuole
What are the parasitic protist?
*Phylum Euglenozoa- Subphylum Kinetoplastida - Trypanosoma (African sleeping sickness) * Phylum Apicomplexa - Plasmodium (Malaria)-Lifecycle
What are the diseases for each parasitic protist and their lifecycles?
*Plasmodium 1. Infected mosquito (anaphales) 2. Infected mosquito bites a human (final host) and injects sporozoites into the blood stream (larva stage). 3. Sporozoites travel by way of the blood to the liver and invade liver cells. 4. Stay in liver for approximately 6-15 days (incubation period) and undergo schizogony (multiple fission, asexual) to produce merozoites. 5. Liver cell ruptures releasing merozoites into the blood stream. 6. Merozoites then invade red blood cells and become trophozoites. 7. Trophozoites undergo schizogony to produce merozoites. 8. Red blood cells rupture releasing merozoites. Hemozoin produced by trophozoites is released causing fever. 2 pathways: a. Merozoites invade more red blood cells and repeat 6-8. b. Some merozoites undergo meiosis to produce gametocytes. • Macro & micro gamete produced. (male & female) • Gametocytes are encysted. 9. Another mosquito bites infected hot and ingests gametocytes. 10. Gametocytes travel to the mosquito's stomach; excysts and macro & micro gametocytes fertilize. This produces a zygote called ookinete. 11. Ookinete burrows through mosquito intestines and forms an oocyst. 12. Oocyst undergos sporogony to produce sporozoites. 13. Sporozoites travel to mosquito's salivary glands. • 1 sporozoite can produce 40k offspring. • Merozoites feed on cell product. • Trophozoites feed on hemoglobin.
How do sponges eat? Reproduce? Habitats?
*Sponges are filter feeders. Most sponges eat tiny, floating organic particles and plankton that they filter from the water the flows through their body. Food is collected in specialized cells called choanocytes and brought to other cells by amoebocytes. *Most sponges are hermaphrodites (each adult can act as either the female or the male in reproduction). Fertilization is internal in most species; some released sperm randomly float to another sponge with the water current. If a sperm is caught by another sponge's collar cells (choanocytes), fertilization of an egg by the traveling sperm takes place inside the sponge. The resulting tiny larva is released and is free-swimming; it uses tiny cilia (hairs ) to propel itself through the water. The larva eventually settles on the sea floor, becomes sessile and grows into an adult. *
Important structures of a living Euglena (w/picture)
*Stigma *Chloroplast *Nucleus *Paramylon Granules *Flagellum
What are the five supergroups of Protist?
- Ameobozoa - Rhizaria - Alveolata - Excavata - Archaeoplastida
What are the main features of supergroup Ameoba?
- Belong to a clade with animals and separate from Rhizarians - Harmless to animals - Formaniferans sercrete a calcareous casting or shell and are found in marine habitats.
What are the main features of supergroup Rhizaria?
- Characterized by pseudopod locomotion - Can be found in fresh or salt water and in soil. - Found in fresh or salt water in the soil. - include Formaniferans, Radiolarians, and Actinopods
Opisthokonta
- Clade - Characterized by combination of flattened mitochondrial cristae and one posterior flagellum on flagellated cells, if such cells are present. - Contains animals and fungi , also microsporidians, choanoflagellates, and some some little known unicells
What are the main features of supergroup Alveolata?
- Containthe tiny cavities, alveoli found inside their plasma membrane - Photosynthetic - Three phyla in this group: Apicomplexa (sporozoans), Ciliophora (ciliates), and the Dinoflagellata (dinoflagellates)
