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Prokaryotic Cells.

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Presentation on theme: "Prokaryotic Cells."— Presentation transcript:

1 Prokaryotic Cells

2 Plantae Fungi Animalia
Kingdom Protista Plantae Fungi Animalia Protista Monera prokaryotic eukaryotic

3 Kingdom Protista Eukaryotic Mostly unicellular
A very heterogeneous group include both heterotrophic and photoautotrophic forms 11 phyla Lots of disagreements Whittaker = “leftovers”

4 Reproduction: binary fission splits into two asexually
multiple fission producing more than two individuals sexually by conjugation (opposite mating strains join & exchange genetic material) 

5 Kingdom Protista 3 informal groups Animal-like protists
Fungus-like protists Plant-like (algal) protists Misleading: some change ~ 45,000 species

6 Animal-like Protists Amoeba Cilliates Flagellates 13,000 species

7 Animal-like Protists Classified by the way they move pseudopodia cilia

8 Heterotrophs ingest small food particles & digest it inside food vacuoles containing digestive enzymes Paramecium consume nutrients from other organisms. Their diet is bacteria, algae, yeast and other micro-organisms. It uses its cilia (strand or tail) and consumes the substance along with water from the mouth of the paramecium. The food enters the gullet or stomach and is stored there. After the gullet is full, the food breaks away and creates a vacuole along with the water. The vacuole moves through the cell, enzymes break down the substance from the inside by entering the vacuole. The nutrients are removed from the vacuole into the cell and the cell gets smaller until it gets released from the cell as waste. Paramecium are interesting cause they eat micro-organisms and even resort to cannibalism. The protist kingdom is very diverse so it is hard to put comparisons on one another without a base.

9 Animal-like protists Sarcomastigophora (amoebas, forams, radiolarian)
Ciliophora (paramecium) Zoomastigophora (trypansoma) Apicocomplexa (Sporozoa)

10 Animal-like Protists Phylum Sarcomastigophora “Amoeba”
Shell-like glass or calcium carbonate structures Radiating projections 13,000 species

11 Note: glass projections

12 Foraminifera Tropics = beaches Most have symbiotic algae

13 Foramenifera: Globigerina ooze
Covers about 36% of the ocean floor

14 Animal-like Protists Phylum Ciliophora (“ciliates”)
Largest, most homogeneous Share few characteristics with others Movement coordinated Sex: 8 mating types 8,000 species

15 Paramecium


17 Animal-like Protists Phylum Zoomastigophora (“zooflagellates”)
Move using flagella:1 to thousands of flagella Some parasites African trypanosomiasis – sleeping sickness – tsetse fly Chagas Disease – kissing bug Leishmaniasis – sand fly giardiasis Vaccines? change protein coat! Gave rise to animals? 1,500 species

18 African sleeping sickness
Tsetse fly Trypansoma

19 The Kissing Bug Chagas disease
Chagas disease is endemic in poor areas in Latin American countries, where an estimated 8 million to 11 million people are infected, according to the CDC. In recent years, immigrants infected with Chagas have come to the U.S., and in 2009, the CDC estimated at least 300,000 migrants carried the disease. It also is known to be carried by kissing bugs in the southern U.S., although the disease is rare here, with only seven cases of locally acquired infection identified. Estimates on the number of worldwide deaths from Chagas per year range from 15,000 to 50,000. But the numbers are declining because of prevention and treatment efforts, said CDC researcher Ellen Dotson. Kissing bugs transmit the disease as they drink blood from humans, typically at night, and spread the parasite through feces. After a brief period of relatively minor symptoms, including a sore at the bite and a fever, the disease usually goes dormant. It re-emerges years or decades later, with severe heart or gastrointestinal problems in about 20 percent to 40 percent of patients. There are treatments for acute infections, but once the disease causes major organ damage, it cannot be reversed. The disease is also transmitted by blood transfusions, organ transplants and in childbirth. Read more: Chagas disease

20 Leishmaniasis Sand fly Leishmania
Leishmaniasis includes two major diseases, cutaneous leishmaniasis and visceral leishmaniasis, caused by more than 20 different leishmanial species. Cutaneous leishmaniasis, the most common form of the disease, causes skin ulcers. Visceral leishmaniasis causes a severe systemic disease that is usually fatal without treatment. Mucocutaneous leishmaniasis is a rare but severe form affecting the nasal and oral mucosa. Leishmaniasis is transmitted by the bite of small insects called sand flies. Many leishmanial species infect animals as well as humans. The distribution is world-wide, but 90% of visceral leishmaniasis cases occur in India, Bangladesh, Nepal, Sudan, Ethiopia and Brazil, while 90% of cutaneous leishmaniasis cases occur in Afghanistan, Algeria, Iran, Saudi Arabia, Syria, Brazil, Colombia, Peru and Bolivia. Leishmania

21 Malaria Mosquito & “victim” Africa = kills 1 million children per year
Thousands of sporozoites injected Vaccine? (US support?) Anopheles Mosquito Life Cycle of the Malaria Parasite A female Anopheles mosquito carrying malaria-causing parasites feeds on a human and injects the parasites in the form of sporozoites into the bloodstream. The sporozoites travel to the liver and invade liver cells. Over 5-16 days*, the sporozoites grow, divide, and produce tens of thousands of haploid forms, called merozoites, per liver cell. Some malaria parasite species remain dormant for extended periods in the liver, causing relapses weeks or months later. The merozoites exit the liver cells and re-enter the bloodstream, beginning a cycle of invasion of red blood cells, asexual replication, and release of newly formed merozoites from the red blood cells repeatedly over 1-3 days*. This multiplication can result in thousands of parasite-infected cells in the host bloodstream, leading to illness and complications of malaria that can last for months if not treated. Some of the merozoite-infected blood cells leave the cycle of asexual multiplication. Instead of replicating, the merozoites in these cells develop into sexual forms of the parasite, called male and female gametocytes, that circulate in the bloodstream.  When a mosquito bites an infected human, it ingests the gametocytes. In the mosquito gut, the infected human blood cells burst, releasing the gametocytes, which develop further into mature sex cells called gametes. Male and female gametes fuse to form diploid zygotes, which develop into actively moving ookinetes that burrow into the mosquito midgut wall and form oocysts.  Growth and division of each oocyst produces thousands of active haploid forms called sporozoites. After 8-15 days*, the oocyst bursts, releasing sporozoites into the body cavity of the mosquito, from which they travel to and invade the mosquito salivary glands. The cycle of human infection re-starts when the mosquito takes a blood meal, injecting the sporozoites from its salivary glands into the human bloodstream . Plasmodium sporozoite gameteocyte

22 Fungus-like Protists Phylum Oomycota (“water molds”; mildew, blights)
475 species Phylum Oomycota (“water molds”; mildew, blights) Some unicellular; others consist of hyphae Decomposers,parasites Cell walls- cellulose Related to algae based on cell wall composition Named after reproductive method No “septa”

23 water molds

24 Downy Mildew

25 Mildew hyphae

26 Fungus-like Protists Phylum Myxomycota (“slime molds”) Bizarre
Bright colors Moving “slime” mass Acellular body 550 species

27 Fungus-like Protists Mildew Water molds Blights 475 species
Downey mildew 475 species Slime molds



30 Slime Mold Maze The slime mold starts out evenly spread through the maze, but when food sources are placed at two ends, the slime mold retracts from everywhere but the shortest path.

31 Plant-like Protists Dinoflagellates Diatoms Euglena Cocolithophore
Green algae Brown Algae Red algae Dinoflagellates Cocolithophore Radiolarian

32 Plant-like Protists Phylum Pyrrophyta (“dinoflagellates”)
Marine and Freshwater Some live in corals Cause “red tide” 1,100 species

33 Zooxanthellae in Coral Polyp

34 Bioluminescence Pyrocystis fusiformis

35 Red Tide HAB (harmful algal blooms) can result in
PSP (paraletic shellfish poisoning) Gonyaulax polyhedra, Gymnodium

36 Red Tide

37 Plant-like Protists Phylum Chrysophyta (“diatoms & golden algae”)
Link to green algae 13,000 species

38 HAB- diatoms 2009 Washington State 10,000 seabirds deaths
The mysterious bird-killing algae that coated Washington's ocean beaches this fall with slimy foam was the biggest and longest-lasting harmful algal bloom to hit the Northwest coast. Now the phenomenon that killed at least 10,000 seabirds — more than any known event of its kind — has scientists consumed by questions: Was it a rogue occurrence, rarely if ever to be repeated, or a sign of some fundamental marine-world shift? And did we cause it? Answers may come slowly. "You can think of it as a jigsaw puzzle with 500 pieces, but we only have about 50," said Julia Parrish, a University of Washington fisheries and oceans professor. This much is known: Toxic blooms of microscopic phytoplankton sometimes called red tides are exploding worldwide, even along pristine waters like the Northwest coast. And the organisms behind these blooms can behave unpredictably, revealing how little we know about the sea. The culprit this fall was a mushroom-shaped single-celled species, Akashiwo sanguinea, that has bloomed in Puget Sound, Chesapeake Bay and saltwater from Europe to Australia and Japan without incident. But something here this time caused the cells to multiply rapidly and break open in a toxic foam. It's been recorded happening only once before — on a smaller scale, in Monterey Bay in California, in 2007. Researchers are trying to gauge whether warming surface waters or more corrosive seas might have played a role in the two blooms, or whether they were caused by a collision of shifting currents and natural atmospheric and weather cycles like El Niño. Or maybe it's all of the above — or something else. "We haven't ever seen this before and now we've had two events in two years," said Raphael Kudela, an ocean-sciences professor and toxic-algae expert at the University of California, Santa Cruz. "If it happens again, I'll be concerned. Four times and I'll be really concerned." Soaplike froth The incident this fall played like something out of a Hitchcock movie: White-winged scoters and surf scoters staggered and collapsed on Olympic Peninsula beaches in September. Then over the next six weeks, loons, grebes and murres were found dead from Neah Bay to Oregon. Just as in Monterey, a soaplike froth coated the natural oils that protect the birds from hypothermia. Researchers are still unearthing its effects: Surfers and kayakers who rode through the foam near Westport, Grays Harbor County, complained of sinus problems and a lingering loss of taste and smell; a pathologist inspecting dead birds found a few whose guts lacked any trace of normal bacteria, raising the possibility they ingested something damaging. Most disturbing to algae experts: The whole incident was unexpected. Akashiwo sanguinea isn't even among the species scientists considered harmful, said Mary Sue Brancato, a marine biologist with the Olympic Coast National Marine Sanctuary. Toxic tides aren't new to the Pacific. A crewman on Capt. George Vancouver's Voyage of Discovery died in 1793 after eating poisoned mussels. The blooms are produced by two classes of microalgae — dinoflagellates and diatoms, tiny creatures that help fuel the marine-food web. In Puget Sound, the most problematic is a type of dinoflagellate that produces a neurotoxin that can reside in shellfish. When ingested by humans, it can cause paralysis and even death. On the coast, the bigger problem is a diatom that blows in from off shore. It can produce domoic acid, which can cause seizures and death in humans. Since being detected in Washington in 1991, this diatom algae has shown up more frequently, shutting down razor-clam harvests in and , and appearing in a giant swath offshore in Some scientists suspect a diatom bloom caused thousands of birds to spiral and crash into cars in California in 1961, an incident that helped inspire Hitchcock's film "The Birds." Along the East Coast and the Gulf of Mexico, as in much of the world, blooms like these are becoming more common, getting bigger and lasting longer. Pollution is believed to influence some events as nutrients drain into the coasts in rivers and as runoff from parking lots and highways. That likely plays a role in the abundant growth of harmful blooms in Puget Sound since the 1950s — but it doesn't appear to be the case along the coast. "We haven't polluted our coastal waters to the same extent they have in the East," said William Cochlan, a research scientist at the Romberg Tiburon Center for Environmental Studies at San Francisco State University. But no one disputes that phytoplankton species are showing up in new places or, as the recent bird-killing bloom revealed, responding in new ways. Indeed, no one expected that particular species, a dinoflagellate, to bloom so massively — or disastrously — off the Northwest coast. And no one knows why it did. Broad consequences? Cracking the secret could prove monumental, helping determine whether we can expect greater economic or biological consequences. Vera Trainer, who runs the harmful-algal-bloom program at the Northwest Fisheries Science Center in Seattle, helped produce a new study showing that a toxic diatom bloom that hits beaches and shutters a razor-clam season for a year could cost Washington's coastal economy $22 million. If other harmful blooms start arriving more often, there's no telling what the cost would be. And that's just for starters. New blooms also could signal a significant shift in the bottom of the ocean's food web that could change the distribution of all sorts of marine and seabird species. Figuring out the causes won't be easy. Kudela notes that changes to coastal upwelling patterns, as well as warming ocean-surface temperatures fueled by climate change in response to greenhouse-gas emissions, could alter the West Coast's mix of phytoplankton. And that could allow one type to out-compete others. Ted Smayda, a phytoplankton expert at the University of Rhode Island, pointed out that a similar foam produced by a related phytoplankton species in Norway does best in waters with a low pH. Scientists already have shown that Pacific Northwest waters are becoming more acidic — meaning a lower pH — as the ocean absorbs billions of tons of carbon dioxide. But Smayda also said it's possible that the blooms are part of some natural ocean rhythm we just don't understand — or a combination of all sorts of other factors. "What if we're just coming into an era where dinoflagellates are coming into their own?" Smayda said. "The bias among investigators, myself included, is that we tend to look for just one factor. But what we have these days is a jumble of events, and we're left asking, 'What the heck is going on?' " Alfred Hitchkock “The Birds” Diatom - Akashiwo sanguinea Domoic acid

39 Plant-like Protists Phylum Euglenophyta (“euglenoids”) 800 species

40 Division Chlorophyta “Green algae” Most freshwater or terrestrial
Some marine 7,000 species

41 Chlorophyta: Green Algae
Halimeda opuntia Codium edule Caulerpa sertularioides Dictyosphaeria cavernosa Caulerpa racemosa

42 Division Phaeophyta “Brown algae” Marine habitats
Example: giant kelp forests 1,500 species

43 Example of complex morphology: Macrocystis
holdfast - attaches to substrate stipe blade - main organ of photosynthesis bladder - keeps blades near the surface Blade Bladder Stipe Holdfast



46 Phaeophyta: Brown Algae
Turbinaria ornata Padina japonica Hydroclathrus clathratus Sargassum echinocarpum Sargassum polyphyllum

47 Division Rhodophyta “Red algae” Most in marine habitats 4,000 species

48 Rhodophyta: Red Algae Ahnfeltia concinna Acanthophora spicifera
Hypnea chordacea Galaxaura fastigiata Asparagopsis taxiformis

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