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VIRUSES

Is a tiny particle that needs a host cell to reproduce and multiply. They are neither alive nor dead… but most scientists consider viruses nonliving particles, since these are NOT cells. VIRUSES.

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VIRUSES

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  1. Is a tiny particle that needs a host cell to reproduce and multiply. They are neither alive nor dead… but most scientists consider viruses nonliving particles, since these are NOT cells. VIRUSES

  2. The organism or cell where a virus multiplies is called a HOST. It provides all the energy the virus needs to reproduce. • The virus is a parasite to the host. VIRUSES

  3. Viruses vary in shape and size: they can be round, robot like or shaped as bullets. They can measure between 20 and 200 nanometers. 1 nm = 1 billionth of a meter Structure: • a protein coat for protection: it allows the virus to attach to the host’s cells. • - an inner core made of genetic material VIRUSES

  4. How do they multiply? ACTIVE VIRUS also called LYTIC CYCLE The virus attaches to the host cell, injects its genetic material, and takes over the functions of the host cell. Once this is done, the host cell starts producing the virus’ proteins and genetic material. These parts will form new viruses, the host cell will burst and the new viruses will go on to infect other cells. VIRUSES http://www.youtube.com/watch?v=XG6XH59yCc0

  5. How do they multiply? HIDDEN VIRUS also called LYSOGENIC CYCLE The virus attaches the cell and injects its genetic material. This genetic material will become part of the genetic material of the host cell. When time passes, the genetic material gets “free” and enters the lytic cycle. VIRUSES http://www.youtube.com/watch?v=XG6XH59yCc0

  6. They were discovered in 1600 by Anton van Leeuwenhoek. How are bacteria cells different? BACTERIA • Bacteria are PROKARYOTES. • Most have a cell wall for protection. • All have a cell membrane that decides what goes inside and outside of the cell. • They also have ribosomes, where proteins are produced. • Some bacteria have a flagellum for movement.

  7. How are bacteria cells different? BACTERIA

  8. How are bacteria cells different?... SHAPE SIZE BACTERIA Spherical Rod like Spiral • They can vary in size, but mainly they are very small.

  9. What do they need to survive? • There are some bacteria that are autotrophic: • There are ones that use the energy from the sun (like plants) • - There are others that use the energy from chemical substances. BACTERIA

  10. What do they need to survive? BACTERIA • There are some bacteria that are heterotrophic: • They consume other organisms or the food that they make.

  11. Under the right conditions, bacteria can reproduce every 20 minutes! BACTERIA How do they reproduce? • Sexual Reproduction • Asexual Reproduction

  12. How do they reproduce?... Asexual Reproduction Binary Fission: one cell divides to form two identical cells. This process involves only ONE parent, and its offspring is identical. BACTERIA

  13. How do they reproduce?... Sexual Reproduction Conjugation: one bacterium transfers some of its genetic material to another bacterium. The result is a bacterium with new combinations of genetic material. This process doesn’t increase the number of bacteria. BACTERIA

  14. Roles in nature… Oxygen and food production: autotrophic bacteria produce oxygen. In the case of food, some undergo fermentation for different products such as cheese and yogurt Recycling: are decomposers. Brake down large chemicals into smaller ones. Return basic chemicals to the environment to reuse. Medicine production: In the intestine for food digestion. In 1970s for production of insulin for people that have diabetes. BACTERIA

  15. Are eukaryotes that live in moist surroundings and are very diverse. Most of them are UNICELULLAR, although there are exceptions. • They can be heterotrophic or autotrophic or both. PROTISTS

  16. Animal-like Protists or Protozoans • Are heterotrophic • Most of them are able to move to obtain their food. • Unicellular PROTISTS

  17. Animal-like Protists or Protozoans… Sarcodines: they forms pseudopods or false foots (AMOEBA) Ciliates: have cilia that are hair like projections (PARAMECIUM) Flagellates: use whip like flagella to move. Some of them live in other organism’s body. Ex: symbiosis with termites Parasites: feed on their host (Plasmodium) PROTISTS

  18. Plant – like Protists • Commonly called algae • Are autotrophic • Some are unicellular and others multicellular or live in colonies • They can be green, brown, red and yelow PROTISTS

  19. Plant – like Protists • Diatoms: unicellular, are food for heterotrophs • Dinoflagellates: unicellular, different colors, two flagella, glow in the dark • Euglenoids: green, unicellular, found in fresh water and can act as heterotrophs. PROTISTS

  20. Plant – like Protists • Red algae: multicellular, absorb small amount of light that reaches deep ocean waters • Green algae: most are unicellular, some form colonies. Live in fresh or salt water; are closed related to plants… • Brown algae: have plant like structures; form underwater “forests” PROTISTS

  21. Fungus – Like Protists Are heterotrophic, have cell wall, use spores to reproduce PROTISTS Types: Slime molds: brilliantly colored; live in moist places; feed on bacteria and other microorganisms Water molds and Downy Mildews: grow as tiny threads that look like fuzz. Attack food crops

  22. What are they? • Are eukaryotes that have cell wall. • Are heterotrophic: they absorb their food • Use spores to reproduce • Need moist warm places to grow FUNGI

  23. Cell Structure • Except for unicellular yeast, cells are arranged in structures called hyphae. These hyphae are threadlike tubes that make up the bodies of multicellular fungi. • In some fungi hyphae are loosely tangled. In others hyphae are packed tightly together. FUNGI

  24. Reproduction • Reproduce by making spores, which are surrounded by a protective covering and can be easily transported through air or water. • The spores are produced in the fruiting bodies, and their appearance may vary depending on the fungus. • In some: the visible part of the fungus. • In others (bread molds), fruiting body is tiny stalk like hyphae. FUNGI

  25. Reproduction • Asexual Reproduction: • Under right conditions of moisture and food fungi make spores asexually. • BUDDING: no spores produced. A small yeast cell grows from the body of a parent cell (think of a tree branch). The new cell breaks and lives on its own. FUNGI

  26. Reproduction • Sexual Reproduction: • Under unfavorable conditions of moisture and food fungi reproduce sexually. • The hyphae of two fungi grow together and genetic material is exchanged. In time, a new reproductive structure grows and start producing spores. The fungi that grow from these spores are genetically different from the parents. FUNGI

  27. Classification • Sac Fungi: • Largest group of fungi • Produce spores is structures like long sacs • Includes yeasts, morels and truffles FUNGI

  28. Classification • Club Fungi: • Produce spores is structures like clubs • Includes mushrooms, bracket fungi and rusts (roya) • The most poisonous are club fungi FUNGI

  29. Classification • Zygote Fungi: • Produce resistant spores: can survive in extreme conditions • Includes molds (Rhizopus), and molds that attack insects. FUNGI

  30. FUNGI Roles in nature… Food production: They cause the bread to rise. Otherwise it would be flat. Recycling: are decomposers. Brake down large chemicals from dead organisms. Return basic chemicals to the environment to reuse. Medicine production: Penicillium. Alexandre Fleming found that no bacteria grew near the mold. Diseases: are parasites for plants and animals.

  31. References • http://lavacaesferica.com/wp-content/uploads/2011/06/Viruses.jpg • http://cienciadelatierra.files.wordpress.com/2010/03/virus.jpg • http://t1.gstatic.com/images?q=tbn:ANd9GcT3Di5Fr_CnlU5Baj5CU8BXUfgg7vF__I2TFYhB5hIYB6_lkfb7 • http://t0.gstatic.com/images?q=tbn:ANd9GcT4zeVuRZh7Dc4NiH4zAFFjTtlIRDRr2S4Byyuukz9s-mxbnoqfDx2U9oXq • http://t3.gstatic.com/images?q=tbn:ANd9GcT9-WsMjzSNGdYumy8IBwe1963N5IVVSCcsi2RcAbvMwiRhnm61DcHOKf2u • http://t0.gstatic.com/images?q=tbn:ANd9GcQtHt_eU2xorTEGveRvxVsIAxvjMvShDXnwIxftwVvXlh76gaEkxhcBcC9CSw • http://t3.gstatic.com/images?q=tbn:ANd9GcQMQrXSZEr1Hxt7jhDRJvEG2PgbSfrq6WvcQcvHIDTs6dXq1FTyiA • http://t0.gstatic.com/images?q=tbn:ANd9GcTPubZzrsuV7igMyDxCLARZr_CH2TYTe0WWiQajGtfacsN5o2caswqktu3J

  32. References • http://t1.gstatic.com/images?q=tbn:ANd9GcR3u0IL-qNym46AFSoe6PxSggLxEjw9fXbmaaLRa7M9WN9zZTGO1_h0Rd_POA • http://t3.gstatic.com/images?q=tbn:ANd9GcTHyTGl-VsmPtm94pPN78S7H4X7WRHr0aAbdZzazsKb5yAg0mAvHw • http://t0.gstatic.com/images?q=tbn:ANd9GcTlR2DUOPCvUyQuYq9RHSJIEc2Pu3mplZAFoTksyi70A0hW3wod • http://t2.gstatic.com/images?q=tbn:ANd9GcR6dei_tYtiR-KciIpqpUox_zmTngDD9j3pvfp6eF3YedKfDZQiPT0yZ51Y • http://t0.gstatic.com/images?q=tbn:ANd9GcS8c42k3o5f8zeM2yv3TDXc34G4GwM8eIkd-UuUvkNwgw8oekU6dg • Jenner, J et. al. 2011. Science Explorer From Bacteria to Plants. Ed. Pearson Prentice Hall • Purves, et al. 2003. Vida, la Ciencia de la Biología.

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