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Tuesday, December 10

  1. page Beaver (deleted) edited
    11:28 am

Monday, December 2

  1. page Orchid edited ... {water plant.jpg} (SL 7) Reproduction and life cycle Life Cycle As in gymnosperms, poll…
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    {water plant.jpg}
    (SL 7)
    Reproduction and life cycleLife Cycle
    As in gymnosperms, pollination is the first step in seed formation. Next, a pollen tube grows before fertilization occurs. Almost all angiosperms have two male gametes that combine their sperm with either the egg or two other haploid nuclei from the female gametophyte. As a result, a diploid zygote and a cell with a triploid nucleus are formed. These two products give rise to the endosperm, a triploid tissue that will nourish the developing embryo. This process, specific to angiosperms, is known as double fertilization.
    In typical sexually reproducing angiosperms, the flower's pollen acts as the sperm cells and are located at the stamen of the flower; the female reproductive organs of a flower are located in the pistil. However, orchids have a unique anatomy. Rather than having stamen and pistils, orchids combine both male and female reproductive organs into one area on the flower called the gynostemium. The anther lies at the top of this column-like structure and contains the pollen, and the sticky concave area below the anther is the stigma, the site for fertilization. While some species have male and female flowers used in sexual reproduction, other species combine the sex organs for self-pollination. Shown below is an anatomical diagram of a Cattleya orchid, a type of orchid which combines its sex organs. (AC) (21)
    {http://www.ctu.edu.vn/~dvxe/Hoa%20Lan/Doc%20on%20web/Orchid%20Anatomy_files/anatomy_cattleya.jpeg} A Cattleya orchid, which exhibits the unique anatomical feature of the orchid known as the gynostemium. (AC) (21)
    Growth and developmentDevelopment
    Together the pollen, the male gametophytes, and the ovules, the female gametophytes, form a zygote. This zygote has a backbone, stem or root, and two cotyledons, or seed leaves. The ovule then develops into a seed that contains a diploid zygote and a triploid endosperm. The seedling then become a flower and repeats this process.
    Even though most angiosperms tend to be dicots, Orchids, on the other hand, are monocots, where seedlings typically have one cotyledon (seed-leaf), in contrast to the two cotyledons typical of dicots. Triploid endosperm is produced during the the life cycle of most angiosperms as a result of double fertilization, where sperm nucleus fuses with two polar nuclei to form nourishing tissue inside the seeds; however, orchids lack an endosperm around their embryo. Like all seed plants, orchids are heterosporous, and their ovules are contained within carpels rather than being exposed on the surface of scales. Male gametophytes are the pollen grains that find their way to pollinate another flower. When pollination occurs, the zygote develops into an embryo, which consists of an embryonic axis and one cotyledon (seed leaf). Because orchids are angiosperms, the ovule develops into a seed containing the products of double fertilization. During germination, orchids have a single embryonic cotyledon that becomes the embryonic first leaves of the seedling. The root system originates in a short-lived embryonic root called the radicle. Monocots form a fibrous root system composed of many thin roots that originate from the stem at ground level.
    Orchids can be either monopodial, meaning one stem grows from a single bud and leaves grow from the apex with the stem growing accordingly (e.g common monopodial orchids are phalaenopsis and vanda), or sympodial, where a few stems grow, they bloom and then die (e.g Cymbidiums and Dendrobiums). (SM) [11,12]
    Integument
    The nameAngiospermname Angiosperm translated to
    Orchids are monocots because they only have one leaf that emerges from the seed (13, 14). The seed of a monocot has 1 cotyledon (14). Orchids have flower parts that are grouped in three or six, and it is unusual with is 3 sepals that organize between its 3 petals and under them. Also orchids have bulbous roots (13). The sperm and male gametophytes are encased in a protective cover called a pollen grain. As it grows the protective cover shrinks. The ovary of an orchid is consists of one or more carpels, which is fused or not fused. Each carpel contains ovules, immature seeds. The entire female reproductive system is made up of the gynoecium, which is made up of the ovary, the stigma, and a pistil. The pistil is a long tube leading from the stigma to inside the ovary. The stigma is a sticky surface where pollen grains adhere (13). (SM)
    Movement
    Animals tend to pollinate angiosperms due to the attractive quality of their flowers. Many flowers provide food rewards for animals such as nectar or pollen grains. In the process of obtaining nectar or pollen, animals transfer pollen from one plant to another, contributing to the plant population’s genetic diversity.
    After fertilization the ovary and the seed inside develop into a fruit. This can promote seed dispersal through animal consumption.
    Sensing the environmentEnvironment
    In order to prevent self-pollination in perfect flowers some angiosperms have stigma that act as screens so that the animals that spread their pollen cannot come in contact with the plant's anthers. Later the next pollinators do come in contact with the anthers, thus leading to fertilization.
    Orchids, like many other plants, can sense the environment and adjust their behavior accordingly. Orchids need to have a bright light, although they cannot have too much direct sunlight because it will dry out the leaves. Blooming will only occur when there is sufficient sunlight because the plant is receiving optimal nutrients and can maintain a flower. In addition, orchids respond well to nights where the temperature is cool, between 10 degrees Celsius and 15 degrees Celsius. This helps induce blooming because the orchids will store the nutrients acquired during photosynthesis in the daytime rather than metabolizing them. Orchids are quite sensitive and a number of factors could cause buds to fall off before flowering, which is a problem for many gardeners. Humidity of the environment must be kept between 50% and 70% for orchids to thrive. They should be grown with a second pot beneath the initial pot with a layer of water to ensure the soil will be kept moist. If the roots of the orchids directly touched this water, the orchid would drown, as the capillaries are only one cell thick. (19) (20) (RS)
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    Like other plants, angiosperms remove their waste through respiration, in the form of carbon dioxide.
    Angiosperms store their wastes in vacuoles to be excreted from the plant. (SL)
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    and salt regulation)Theregulation)
    The
    characteristics of
    There are some species of orchid that have the ability to undergo Crassulacean acid metabolism, or CAM photosynthesis, that allows them to survive in particularly dry environments such as deserts. Normally, plants have their stomata open during the day to take in carbon dioxide and close them at night, which results in a large loss of water because it is hotter during the day. With CAM photosynthesis, the orchid opens the stomata at night instead when it is cooler and fixes the carbon dioxide during the day. In some extreme cases, the orchid can enter a CAM-idle state that occurs when conditions are extremely arid. During this state, the plant can leave the stomata closed for extended periods of time during which the oxygen given off in photosynthesis is used in respiration and the carbon dioxide given off in respiration is used in photosynthesis. (4) (CM)
    Internal circulation
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    {http://home.earthlink.net/~dayvdanls/pressureflow.gif}
    Plants move nutrients around through vessels called xylem and phloem. Xylem moves water while phloem moves food. Nutrients move because of a food gradient. One cell that produces sugar must give its sugar to a cell with low glucose levels. This relationship is called source to sink. The source cell will create sugar, which, through active transport, will move into the phloem. Because of an increase in solutes, the phloem becomes hypertonic to the xylem. This results in water moving into the phloem through osmosis. The solutes (glucose), looking for a hypotonic environment, will move to the sink cell and, through active transport, leave the phloem. The water, now in a hypotonic solution, will undergo osmosis and return to the xylem (15) RG
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    (i.e. endocrine system)Respirationsystem)
    Respiration
    and photosynthesis
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    and oxygen. {photosynthesis_equation.jpg}
    {photosynthesis_equation.jpg}

    (SL 6)
    QUESTIONS:Review Questions
    1. How do orchids work in their ability to regulate their internal environment? (SM)
    2. Explain the reproduction cycle of a normal orchid. (SM)
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  2. page Pigeon edited ... Habitat and Niche Pigeons can be found around the world and are able to live in a variety of …
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    Habitat and Niche
    Pigeons can be found around the world and are able to live in a variety of environments, due to their ability to self-regulate their temperature, water, and salt systems. They are able to fly and travel great distances, allowing them to spread locally. They are very adaptable to their environment.
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    12, 13)
    Predator Avoidance
    Pigeons use flight to avoid predators as well as practice group living and alarm signaling. The more Pigeons in a group, the sooner one will spot a predator and signal the danger to those surrounding them.
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    8:21 am

Sunday, December 1

  1. page Yeast edited ... Genus: Saccharomyces (16) (SL) ... to produce diploid haploid cells. Yeast ... assoc…
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    Genus: Saccharomyces
    (16) (SL)
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    to produce diploidhaploid cells. Yeast
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    associate with the word yeast is
    Yeasts are eukaryotes characterized by their enclosed nucleus with a double DNA strand, as well as organelles that perform different functions. They are also single-celled, heterotrophic, fungi organisms, meaning that they cannot fix their own carbon and must obtain it through autotrophic organisms. (7) Fungi are characterized by their mix of traits that belong to plants and animals. Fungi consume organic matter and have an enclosed nuclei like both animals and plants but don't have chlorophyll like plants or the ability to move like animals. (8) (RG)
    Relationship to Humans
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    Predator Avoidance
    Predator Avoidance
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    barrier to invaders and protect against invaders and foreign materials.
    Although yeast lack an effective predator avoidance strategies, they are able to survive in great numbers because they reproduce so easily and at such a high rate. (3)
    One of the predators of yeast is paramecium. The video below shows paramecium consuming yeast for nutrient acquisition. The yeast has been digested when the red particles turn blue. (MT)
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    Nutrient Acquisition
    Yeasts, like all fungi, digest their food outside their bodies by using digestive enzymes to break down large food particles. Once the food is broken down, the yeasts can then absorb their nutrients directly across their cell membrane because they are unicellular creatures in a process called absorptive heterotrophy. Because they digest their foods outside of their body, yeasts are often found on fruits such as figs and grapes to gain nutrients or in the guts of insects to help the insects break down materials that are difficult to digest, all the while gaining their own nutrients. (3)
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    hosts, or mutualistsmutualists, which live
    The enzymes that saprophytes use to break down organic molecules from dead organic matter are hydrolytic enzymes, meaning that they use the process of hydrolysis to break chemical bonds by the addition of water. After the originally large organic molecules are broken down into smaller molecules, the yeast can now absorb the smaller molecules. This allows yeast and other fungi to act as decomposers, as they break down large molecules from dead organisms into smaller molecules. (21) (RS)
    Reproduction and Life Cycle
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  2. page Clam edited Clams Noosha Uddin {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shel…

    Clams
    Noosha Uddin
    {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg} Tridacna gigas (18)
    I. Classification/Diagnostic Characteristics
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  3. page Clam edited ... 17. Scott, Paul V. "ITIS Standard Report - Error." ITIS Standard Report - Bivalvia L…
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    17. Scott, Paul V. "ITIS Standard Report - Error." ITIS Standard Report - Bivalvia Linnaeus, 1758. Integrated Taxonomic Information System, n.d. Web. 18 Nov. 2013.
    18. Tridacna Gigas

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  4. page Clam edited Clams {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg} Giant Cla…

    Clams
    {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg} Giant Clam (http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg) Tridacna gigas (18)
    I. Classification/Diagnostic Characteristics
    Clams belong to the phylum Mollusca, which is made up of four major clades: chitons, gastropods, bivalves, and cephalopods. All of these clades share the same three characteristics that differentiate mollusks from other phyla:
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    1. Wahlert, John H., and Mary Jean Holland. "Mollusca, Laboratory Notes for BIO 1003." Mollusca, Laboratory Notes for BIO 1003. N.p., n.d. Web. 24 Nov. 2013.
    2. Maté, B. "The Habitat of Clams." //EHow//. Demand Media, 09 June 2011. Web. 14 Nov. 2013.
    3. clam anatomy pictureClam Anatomy Picture
    4. "Animal Planet." Animal Planet. N.p., n.d. Web. 18 Nov. 2013.
    5."Phytoplankton, A Necessity For Clams." Innovative Marine Aquaculture. N.p., n.d. Web. 18 Nov. 2013.
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    16. "Food Gal » Blog Archiv » A Daring Pairing with Clam Udon." Food Gal » Blog Archiv » A Daring Pairing with Clam Udon. N.p., n.d. Web. 25Nov. 2013.
    17. Scott, Paul V. "ITIS Standard Report - Error." ITIS Standard Report - Bivalvia Linnaeus, 1758. Integrated Taxonomic Information System, n.d. Web. 18 Nov. 2013.
    18. Tridacna Gigas

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    8:39 pm
  5. page Clam edited Clams {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg} Giant Cla…

    Clams
    {http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg} Giant Clam (http://www.internetstones.com/image-files/tridacna-gigas-giant-clam-shell.jpg)

    I. Classification/Diagnostic Characteristics
    Clams belong to the phylum Mollusca, which is made up of four major clades: chitons, gastropods, bivalves, and cephalopods. All of these clades share the same three characteristics that differentiate mollusks from other phyla:
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    Phylum: Mollusca
    Class: Bivalvia Linnaeus (Bivalves, Clams, Palourdes)
    (SL 18)17)
    II. Relationship to Humans
    Clams belong to the clade of protostomes, and together with deuterostomes they form the bilaterians. Of all other major clades, the protostomes are the closest to humans, which belong with the deuterostomes along with other chordates.
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    and pasta. (SF)(16)(17)(SF)(15)(16)
    {pasta2.jpg} Pasta dish made with clams
    III. Habitat & Niche
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    Underneath the clam's shell is a lining called the mantle. Encased in the mantle are gills which are used for breathing and eating purposes. Clams have two openings in their mantle call siphons. When they are ready to eat, clams will stick the siphons out of their shells, and use their cilia to create a current that brings food and water toward the incurrent siphon. Excess water travels back to the ocean through the excurrent siphon. The water contains microorganisms such as plankton which the clams eat. These organisms cling to tiny hairs on the gills called cilia (4). The gills have special grooves that sort the food into acceptable type and size. Accepted food is transferred to the mouth, traveling to the clam's internal digestive system. As food travels down the esophagus mucus is added to it. Enzymes in the stomach, as well as a stiff rod of hardened mucus, which rotates with the help of cilia, are used to break down much of the food into nutrients the clam can use. The nutrients then enter a digestive gland where the nutrients come in contact with cells that can harness them. The cells are bathed in blood that carries nutrients to all cells in the body. Unused nutrients are sent down the intestines and expelled through the anus (5). (RG)
    VI. Reproduction & Life Cycle
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    float away (12).(11). (AG)
    VII. Growth & Development
    In clams, like in other protostomes, during gastrulation the mouth arises first from the blastopore, later followed by the anus. Further development of the clam is not presented in any more detail. This is a major difference between protostomes and deuterostomes, where the latter’s blastopore forms the anus first, then followed by the mouth.
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    energy. (JM 10)9) Clams can
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    shell. (JM 11)10)
    VIII. Integument
    Clams have a mantle which secretes the two part shell that extends over the sides of the body to the top serving as a defense mechanism and a cover to protect its internal organs.
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    the situation. (9)(8) (YR)
    {http://www.exploringnature.org/graphics/mollusks/clam_diagram_color72.jpg}
    The following image pinpoints essential structure for bivalves such as clams. Important structures to identify include placement of the foot, the location of the mouth and anus, and the siphon (responsible for water regulation). (SR)
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    X. Sensing the Environment
    With its foot as a means of moving around and its incurrent siphon to filter in food and its gills and excurrent siphon to filter out water and other waste respectively, clams rely on tactile sense to be able to recognize their environment.
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    closing its shell.(15)shell.(14)
    XI. Gas Exchange
    The gills of clams filter out water while feeding through the excurrent siphon. With an open circulatory system, oxygen is delivered directly to the body’s internal organs through the fluid-filled hemocoel consisting of blood and other fluids.
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    XII. Waste Removal
    While food and other nutrients enter through the incurrent siphon, water and gametes exit the body through the excurrent siphon.
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    the clam. (13)(12) (RS)
    XIII. Environmental Physiology
    Clams today are found in both freshwater and marine environments, so the general temperature, water and salt variation may vary between different kinds of clams due to evolution.
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    flow. (AC) (14)(13)
    XIV. Internal Circulation
    As one of the two major groups of protostomes, blood vessels of mollusks do not form a closed circulatory system. Rather, blood and other fluids are carried into a large, fluid-filled hemocoel, where they move around the animal’s body and deliver oxygen to internal organs. Fluids then reenter the blood vessels and are carried by the heart.
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    5."Phytoplankton, A Necessity For Clams." Innovative Marine Aquaculture. N.p., n.d. Web. 18 Nov. 2013.
    6. Nordsieck, Robert. "Mussels and Clams (Bivalvia)." Mussels and Clams (Bivalvia). N.p., n.d. Web. 18 Nov. 2013.
    7. http://video.nationalgeographic.com/video/animals/invertebrates-animals/other-invertebrates/ray_cownosed_eats_clam/
    8.http://www.glf.dfo-mpo.gc.ca/Gulf/By-The-Sea-Guide/Activities-35
    "Video -- Clams: Not Just for Chowder -- National Geographic." National Geographic. Livefyre, n.d. Web. 17 Nov. 2013.
    8. "Bivalvia." Bivalvia. SUNY Cortland, n.d. Web. 17 Nov. 2013.

    9. http://paleo.cortland.edu/tutorial/Bivalves/bivalvia.htm"Hard Clams - Lifecycle." Hard Clams - Lifecycle. Rhode Island Sea Grant, n.d. Web. 17 Nov. 2013.
    10. http://barnegatshellfish.org/clam_lifecycle_01.htm
    11.http://www.cbsnews.com/8301-205_162-57612409/ming-the-clam-worlds-oldest-animal-was-actually-507-years-old/
    Elliot, Danielle. "Ming the Clam, World's Oldest Animal, Was Actually 507 Years Old."CBSNews. CBS Interactive, 14 Nov. 2013. Web. 17 Nov. 2013.
    11. "Clams | Washington Department of Fish & Wildlife." Clams | Washington Department of Fish & Wildlife. Washington Department of Fish & Wildlife, n.d. Web. 18 Nov. 2013.

    12. www.wdfw.wa.gov/fishing/shellfish/clams/
    13.
    Hagerman, Howard.
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    Nov. 2013.
    14.

    13.
    "Mollusks -
    ...
    Nov. 2013.
    15.http://www.eoearth.org/view/article/154665/
    16"Top

    14. Hebert, Paul D. N. "Mollusca." Mollusca. Biodiversity Institute of Ontario, 11 Oct. 2007. Web. 18 Nov. 2013.
    15. "Top
    10 Consumed
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    Nov. 2013.
    17."Food

    16. "Food
    Gal »
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    25Nov. 2013.
    18.http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=79118

    17. Scott, Paul V. "ITIS Standard Report - Error." ITIS Standard Report - Bivalvia Linnaeus, 1758. Integrated Taxonomic Information System, n.d. Web. 18 Nov. 2013.

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