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    How to use a dichotomous key and genetic engineering

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    Part 1: Submit a list , Organism 1 through Organism 7,(Attached) with your decision about the classification for each, as well as the choices you made for each step on the key. Spelling counts as does correctly identifying each organism. State exactly what you see on the key: Class Trematoda, or Phylum Porifera, for example. NO common names like worm, or snail.
    names like worm, or snail.

    The trick to using this key is to understand (or look up) the words used in each descriptive line. What is radial symmetry? What is bilateral symmetry?

    If you know the common name of each organism, you may want to do research about the organism to determine, for example, if it has an internal or external skeleton.

    Part 2: You are a geneticist working for a firm that specializes in plant biotechnology. Explain what specific parts (fruit, seeds, stems, roots, etc.) of the following plants you would try to alter by genetic engineering, what changes you would try to make, and why, on a) corn, b) tomatoes, c) wheat, and d) avocados.

    Only a few hundred of the hundreds of thousands of species in the plant kingdom have been domesticated for human use. One example is the almond. The domestic almond is nutritious and harmless, but its wild precursor can cause cyanide poisoning. The oak makes potentially nutritious seeds (acorns) that contain very bitter-tasting tannins. If we could breed the tannin out of acorns, they might become a delicacy. Why do you suppose we have failed to domesticate oaks?

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    Solution Preview

    Dichotomous key

    This question is asking you to determine the scientific phylum or class for which each organism pictured belongs to. To do this you will follow the dichotomous key through a series of questions that act to direct you to the appropriate category. This key is very similar to the procedure you may have gone through before when using a Microsoft Software help window; a question is asked and depending on how you answer it you are directed to different help text. For example does the computer's mute button work, for yes see answer A for no continue to the next question.
    For your question you want to examine the picture of the animal and using that picture choose the appropriate answer for each question (a or b). The column on the far right of each answer row will either have the taxonomic group of the animal or the next question you should refer to to determine the taxonomic group. Continue on with the questions until you come to a taxonomic category in the right column, in which case you have your answer.

    Definitions of the technical terms in the key:

    Irregular shape: no symmetry. Think amoeba.

    Regular shape: symmetry of some kind; a similarity in left and right halves or different parts. See symmetry below.

    Radial symmetry: This form of symmetry evolved before bilateral and describes animals that can be divided into many planes to create two halves that are mirror images, for example starfish and many jellyfish.

    Bilateral symmetry: In this form of symmetry only one single plane can divide the animal ...

    Solution Summary

    This solution defines terms in a dichotomous key and explains how to use the key to identify species. It also discusses genetic engineering as it relates to agriculture.