20-1 The Kingdom Protista

Size: px

Start display at page:

Download "20-1 The Kingdom Protista"

Emory Cross
6 years ago
Views:

20-1 The Kingdom Protista Protists are that are not members of the Plant, Animal, or Fungi Kingdoms. The Kingdom Protista may include more than 200,000 species.

1 20-1 The Kingdom Protista Protists are that are not members of the Plant, Animal, or Fungi Kingdoms. The Kingdom Protista may include more than 200,000 species. Most, but not all, protists are. One way protists can be classified is by how they obtain nutrition: are animal-like protists. are plant-like protists. and parasites are fungus-like protists. (Note: also heterotrophic)

2 Evolution of Protists Chloroplast The first eukaryotic organisms on Earth were. The theory of suggests that mitochondria and chloroplasts in eukaryotic cells may have descended from that lived inside larger cells.

Zooflagellates (P. Zoomastigina) 2. Sarcodines (P.

3 20 2 Animal-like Protists: Protozoans There are four of -like protists. They are classified by their means of : 1. Zooflagellates (P. Zoomastigina) 2. Sarcodines (P. Sarcodina) 3. Ciliates (P. Ciliophora) 4. Sporozoans (P. Sporozoa)

Ciliates Cilia sweep food particles into the (Ciliophora). The gullet traps the particles and forces them into food vacuoles. The food vacuoles fuse with lysosomes which contain digestive.

4 Ciliates Cilia sweep food particles into the (Ciliophora). The gullet traps the particles and forces them into food vacuoles. The food vacuoles fuse with lysosomes which contain digestive. Once the material in the food vacuole is digested, the waste material empties through the anal pore. Paramecia possess two types of nuclei: The nucleus keeps multiple copies of most genes that the cell needs in its day-to-day existence. The nucleus contains a copy of all of the cell's genes. In fresh water, water moves into the paramecium by. Excess water is collected in contractile vacuoles, cavities in the cytoplasm that are specialized to collect water. Once full, they, pumping water out of the organism. use cilia for feeding and movement. Cilia are short projections that propel a cell or surrounding fluid. One type of ciliate is a. In a paramecium, the cilia are grouped into rows and bundles, and beat in a regular pattern. are bottle-shaped structures found just below the surface of the cell membrane that are used for defense.

5 Ciliates (Ciliophora) Ciliates reproduce by mitosis and. When placed under stress, paramecia may engage in which allows them to exchange material with other individuals and increase genetic.

Ciliate Conjugation Macronucleus Micronucleus Two paramecia attach

produces four micronuclei, three of which disintegrate.

MEIOSIS Disintegration & MITOSIS The two cells exchange micronucleus

The disintegrate, and each cell forms a new macronucleus from its.

6 Ciliate Conjugation Macronucleus Micronucleus Two paramecia attach themselves to each other. produces four micronuclei, three of which disintegrate. The remaining micronucleus in each cell divides again by. MEIOSIS Disintegration & MITOSIS The two cells exchange micronucleus from each pair which. The disintegrate, and each cell forms a new macronucleus from its. Conjugation is a form of reproduction. In large populations, conjugation helps produce and maintain genetic. Exchange of micronuclei Macronuclei disintegrate New macronuclei form Genetically identical paramecia

Zooflagellates (Zoomastigina) STD Sand Fly vector

African Sleeping Sickness Animal-like protists that

Most zooflagellates have one or two flagella, although

7 Zooflagellates (Zoomastigina) STD Sand Fly vector Infects skin and/or internal organs Tsetse Fly vector African Sleeping Sickness Animal-like protists that swim using are called zooflagellates. Most zooflagellates have one or two flagella, although a few species have many. Most zooflagellates reproduce by mitosis and cytokinesis ( ).

Sarcodines include: Foraminiferans, Amoebas & Heliozoans ( sun

Sarcodines (Sarcodina) Contractile vacuole Pseudopods Nucleus

cytoplasmic projections used for feeding or movement.

8 Sarcodines include: Foraminiferans, Amoebas & Heliozoans ( sun animals ). Sarcodines (Sarcodina) Contractile vacuole Pseudopods Nucleus Food vacuole are animal-like protists that have, temporary cytoplasmic projections used for feeding or movement. are flexible, active cells with thick pseudopods that extend out of the central mass of the cell. Cytoplasm into the pseudopod, and the rest of the cell follows. This type of locomotion is known as movement. Amoebas reproduce by mitosis and cytokinesis ( ).

9 Sporozoans (Sporozoa) do not move on their own they are on a wide variety of organisms, including worms, fish, birds, humans and other mammals. Many sporozoans have life cycles that involve more than one. They reproduce by, which attach to a host cell, penetrate, and live within it as a parasite. Sporozoites Possibly all mammals, including humans, can become infected with Toxoplasma. One source of infection is the ingestion of material contaminated with sporulated oocysts excreted by cats. For example, children of crawling and dirt-eating ages are believed to be at higher risk for infection. Toxoplasmosis can also be acquired through the ingestion of undercooked meat containing tissue cysts or tachyzoites. In fact, most infections in the United States and Europe among adults are probably acquired from undercooked meat. Mutton and pork are more common sources than beef. Toxoplasma can also be transmitted from mother to fetus, often with dire consequences. Congenital transmission can only occur during an acute infection (ie, sporozoites) acquired during pregancy. Mothers with a chronic infection acquired before the pregnancy are not at a risk for transmitting Toxoplasma.

Animal-like Protists and Disease The Sexual Phase A female Anopheles mosquito bites a human infected with malaria and picks up Plasmodium gamete cells.

10 Animal-like Protists and Disease The Sexual Phase A female Anopheles mosquito bites a human infected with malaria and picks up Plasmodium gamete cells. Gametes fuse to form zygotes, meioses occurs, and sporozoites are produced and migrate to salivary gland. Infected red blood cells burst, releasing merozoites that infect other red blood cells. Some cells release gametes that can infect mosquitoes. Infected mosquito bites another human, injecting saliva that contains Plasmodium sporozoites. The Asexual Phase Sporozoites infect liver cells and multiply asexually. Infected liver cells burst, releasing Plasmodium cells called merozoites. Merozoites infect red blood cells and reproduce asexually. Some animal-like protists cause serious diseases, including and African sleeping sickness. Malaria is one of the world s most serious infectious diseases, killing as many as million people each year. The sporozoan, which causes malaria, is carried by the female Anopheles.

11 Animal-like Protists and Disease 1. African Sickness 2. Dysentery 3. Tsetse fly Trypanosoma brucei Note abundant large amebic trophozoites (Entamoeba histolytica) with clear bubbly cytoplasm. 40X

Ecology of Animal-like Protists Many animal-like protists are

Some live with other organisms (parasitic/mutualistic) Some recycle

Some live in water, where they are eaten by tiny animals, which in

12 Ecology of Animal-like Protists Many animal-like protists are essential to the living world. Some live with other organisms (parasitic/mutualistic) Some recycle nutrients from dead organic matter ( ). Some live in water, where they are eaten by tiny animals, which in turn serve as food for larger animals (1º ). The protist Trichonympha lives within the digestive systems of. It breaks down, allowing termites to digest wood.

13 20 5 Funguslike Protists Like fungi, funguslike are that absorb nutrients from dead or decaying organic matter. Unlike most true fungi, funguslike protists contain centrioles. They also lack the cell walls of true fungi.

At one stage of their life cycle, slime molds look just

14 Slime Molds Slime molds are funguslike protists that play key roles in recycling organic material. At one stage of their life cycle, slime molds look just like. At other stages, they form moldlike clumps that produce, almost like fungi.

Fruiting body Spores Emerging amoebas Cellular Slime Molds (Acrasiomycota) Solitary cell Aggregated amoebas Zygote Fruiting body Migrating colony Most slime molds are free-living cells not easily

15 Fruiting body Spores Emerging amoebas Cellular Slime Molds (Acrasiomycota) Solitary cell Aggregated amoebas Zygote Fruiting body Migrating colony Most slime molds are free-living cells not easily distinguishable from soil. In nutrient-rich soils, these amoeboid cells produce diploid zygotes. When food is scarce, the cells asexually produce. The amoeboid cells emit chemicals to attract others of the same species. Cells gather into a that functions like one organism. The colony moves slightly, then stops to produce a fruiting body or, a slender reproductive structure that produces spores. The spores are scattered from the fruiting body, each producing one cell.

Acellular (Plasmodial) Slime Molds (Myxomycota) Fertilization Mature sporangium Spores Germinating Young sporangium Zygote Feeding Mature plasmodium plasmodium slime molds begin as amoeba-like

16 Acellular (Plasmodial) Slime Molds (Myxomycota) Fertilization Mature sporangium Spores Germinating Young sporangium Zygote Feeding Mature plasmodium plasmodium slime molds begin as amoeba-like zygotes. When they aggregate, their cells fuse to produce super cell-like structures known as. Fruiting bodies, or sporangia, arise from the plasmodium producing haploid by meiosis. The spores scatter and germinate into flagellated cells which fuse to produce, amoeba-like zygotes.

Antheridium (male nuclei) MEIOSIS Zoosporangia Oogonium (egg cells) Water Molds (Oomycota) FERTILIZATION Zygotes (2N) SEXUAL REPRODUCTION Flagellated Spores (2N) ASEXUAL REPRODUCTION Hypha

17 Antheridium (male nuclei) MEIOSIS Zoosporangia Oogonium (egg cells) Water Molds (Oomycota) FERTILIZATION Zygotes (2N) SEXUAL REPRODUCTION Flagellated Spores (2N) ASEXUAL REPRODUCTION Hypha Germination and mitosis Mycelium (2N), or water molds thrive on dead or decaying organic matter in water and some are plant on land. Like true fungi, water molds produce thin filaments known as. Unlike true fungi, they have cell walls made of and produce spores. During asexual reproduction, portions of the hyphae develop into, which are spore cases. Each produces spores that swim in search of food, then develop into hyphae, which grow.

occurs in specialized structures formed by the. The produces male nuclei.

18 Egg cells (N) Antheridium Water Molds (Oomycota) FERTILIZATION Zygotes (2N) MEIOSIS Oogonium Mycelium (2N) Male nuclei (N) Fertilization Flagellated Zoospores (2N) Zoosporangia reproduction occurs in specialized structures formed by the. The produces male nuclei. The produces female nuclei. Fertilization occurs within the oogonium, and the spores that form develop into new organisms.

19 Ecology of Funguslike Protists Slime molds and water molds organic material. After organisms die, their tissues are broken down by slime molds, water molds, and other. Some funguslike protists can harm living things. Land-dwelling water molds cause a number of diseases, including mildews and blights. A water mold was responsible for the Great Famine in the 1800s.

20-3 Plantlike Protists: Unicellular Algae Plantlike protists contain, carry out photosynthesis, are commonly called and are sometimes classified with plants.

20 20-3 Plantlike Protists: Unicellular Algae Plantlike protists contain, carry out photosynthesis, are commonly called and are sometimes classified with plants. Chlorophyll and accessory allow algae to harvest and use the energy from. Some algae have evolved different forms of chlorophyll a, b, and c that absorb different of light. Accessory pigments absorb light at different wavelengths than chlorophyll, giving algae a variety of.

21 Plantlike Protists One trait used to classify algae is the type of photosynthetic they contain. The four of unicellular algae are: 1. Euglenophyta 2. Chrysophyta 3. Bacillariophyta (Diatoms) 4. Dinoflagellata Euglena Synura Ceratium Synedra

Euglenophytes (Euglenophyta) Euglenophytes are plantlike protists Pellicle that have two but no cell. Two flagella emerge Carbohydrate from a gullet.

Chloroplast Near the gullet is a reddish pigment Nucleus known as the, which helps find sunlight to power photosynthesis. Euglenas can also live as.

22 Euglenophytes (Euglenophyta) Euglenophytes are plantlike protists Pellicle that have two but no cell. Two flagella emerge Carbohydrate from a gullet. The longer of the storage bodies flagella spins so it the organism rapidly through the water. Chloroplast Near the gullet is a reddish pigment Nucleus known as the, which helps find sunlight to power photosynthesis. Euglenas can also live as. Euglenas store carbohydrates in small storage bodies. Instead of a cell wall, they have an intricate cell membrane called a, which folds into ridges, each supported by microtubules. Euglenas reproduce by binary fission. Contractile vacuole Eyespot Gullet Flagella

Chrysophytes (Chrysophyta) & Diatoms (Bacillariophyta) Members of the

They reproduce both asexually and sexually.

23 Chrysophytes (Chrysophyta) & Diatoms (Bacillariophyta) Members of the phylum are a diverse group of plantlike protists that have -colored chloroplasts. The cell walls of some chrysophytes contain the pectin rather than cellulose, some both. Chrysophytes store food in the form of rather than starch. They reproduce both asexually and sexually. Most are, but some form threadlike colonies. Bacillariophyta ( ) produce thin, delicate cell walls rich in (Si) the main component of glass. The walls are shaped like the two sides of a dish or flat pillbox, with one side fitted snugly into the other.

(Pyrophyta) About half of the are photosynthetic; the other

Most dinoflagellates reproduce by binary fission.

24 (Pyrophyta) About half of the are photosynthetic; the other half live as. Dinoflagellates have two flagella that fit in between two thick plates of that protect the cell. Most dinoflagellates reproduce by binary fission. Many are and when agitated, give off light as a warning to predators. These species produce a which can kill fish and humans that eat shellfish during a tide.

Ecology of Unicellular Algae Plantlike protists are

the of the food web in many aquatic ecosystems.

organisms found near the surface of the ocean.

25 Ecology of Unicellular Algae Plantlike protists are important to freshwater and marine because they make up the of the food web in many aquatic ecosystems. constitute the population of small, photosynthetic organisms found near the surface of the ocean. They carry out half of photosynthesis and provide nourishment for many organisms.

26 Ecology of Unicellular Algae Many protists are vital in sewage and other wastes. When waste is excessive ( ), algae may grow into enormous masses known as, which deplete the water of nutrients. Their robs water of oxygen, killing fish and invertebrate life.

27 20-4 Plantlike Protists: Colonial/Multicellular Algae The three of algae that are largely multicellular are: 1.red algae ( ) 2.brown algae ( ) 3.green algae ( )

Red Algae (Rhodophyta) Red algae are able

28 Red Algae (Rhodophyta) Red algae are able to live at great due to their efficiency in harvesting light energy. Red algae contain chlorophyll a and reddish accessory pigments called which absorb blue light, enabling red algae to live deep in the ocean.

29 Brown Algae (Phaeophyta) Fucoxanthin Brown algae contain chlorophyll a and c, as well as a brown accessory pigment,, which absorbs blue-green to yellowgreen light. Brown algae are the and most complex of the algae. All are and most are marine, commonly found in cool, shallow coastal waters of temperate or arctic areas.

30 Fucus (Kelp), a common brown alga. Blades Leaflike structures (AKA ) Bladder -filled bladders keep the alga and upright. Stipe A flattened structure. Holdfast the alga to rocks.

31 Green Algae (Chlorophyta) Charophyceans are named after the stonewort, Chara. Green algae share many characteristics with, including their photosynthetic pigments and cell wall composition. The ancestors of modern land plants looked like certain species of living green algae,. Green algae live in fresh and salt water, and moist land areas. Many species live most of their lives as single cells. Others form, groups of similar cells that are joined together but show few structures. A few are and have specialized structures.

sexually. In suitable living conditions, this haploid cell reproduces asexually, producing cells called zoospores by mitosis.

32 The zygote grows a thick protective wall that can survive conditions that otherwise would kill it. Reproduction in Green Algae Release of haploid cells zoospores Zygote Pairing of plus and minus gametes If conditions become unfavorable, Chlamydomonas can also reproduce sexually. In suitable living conditions, this haploid cell reproduces asexually, producing cells called zoospores by mitosis. The life cycles of many algae include both a diploid and a generation. Switching between haploid and diploid stages during a life cycle is known as of generations. Many alga also shift between sexual and asexual reproduction. The unicellular Chlamydomonas spends most of its life in the stage.

Reproduction in Green Algae Sporophyte Zygote Mitosis Meiosis Spores Gametes fuse Fertilization Gametes Female Mitosis gametophyte Mitosis Male gametophyte The life cycle of the green alga Ulva

33 Reproduction in Green Algae Sporophyte Zygote Mitosis Meiosis Spores Gametes fuse Fertilization Gametes Female Mitosis gametophyte Mitosis Male gametophyte The life cycle of the green alga Ulva involves alternation of. One generation are, haploid, gamete-producing Ulva. When male and female gametes fuse, they produce a diploid zygote which grows into the next generation, a diploid, spore-producing Ulva.

34 Ecology & Human Use of Algae Algae produce half of Earth s through photosynthesis. Algae is found in sushi, ice cream, and other foods. from algae are used to make plastics, waxes, transistors, deodorants, paints, lubricants, and artificial wood. thickens nutrient mixtures in scientific labs.

Biology. Slide 1of 34. End Show. Copyright Pearson Prentice Hall

Biology. Slide 1of 34. End Show. Copyright Pearson Prentice Hall Biology 1of 34 20 5 Funguslike Protists 2of 34 20 5 Funguslike Protists Similarities and differences between funguslike protists and fungi Like fungi, g, funguslike protists are heterotrophs that absorb