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Bio Homework Review (Please check and Correct)

  1. Feb 16, 2012 #1
    I answered all questions to what I know, and what I think, one I really didn't know the answer

    1. The smallest unit of a chemical element that still has the properties of that element is a(n)
    A) amino acid.
    B) molecule.
    C) atom.
    D) bond.


    2. A proton has _______ charge.
    A) no
    B) a neutral
    C) a negative
    D) a positive


    3. How many hydrogen atoms are in a molecule of C8H10N4O2?
    A) 8
    B) 10
    C) 24
    D) 20

    4. The strongest possible chemical link between two atoms is a(n)
    A) covalent bond.
    B) hydrogen bond.
    C) noncovalent bond.
    D) ionic bond.


    5. Electrons are found
    A) in the nucleus of an atom.
    B) only in complex molecules.
    C) in a shell that surrounds the atom’s nucleus.
    D) in both the nucleus and inner shell of an atom.


    6. Ionic bonds
    A) result from the sharing of electrons between atoms.
    B) form only between polar molecules.
    C) form between atoms that develop opposite charges.
    D) are due to protons repelling each other.


    7. Individual water molecules are pulled toward each other by _______ bonds.

    A) covalent
    B) hydrogen
    C) peptide
    D) ionic


    8. In the chemical reaction , _____ are considered reactants.
    A) CO2; and H2O
    B) O2 and H2O
    C) C6H12O6 and O2
    D) C6H12O6 and CO2

    (Don't Know honestly)

    9. A solution with a pH of 3 is
    A) acidic.
    B) nonpolar.
    C) basic.
    D) neutral.

    10. The sugar glucose has an important role
    A) in the formation of proteins.
    B) in short-term energy storage.
    C) in the formation of membranes.
    D) as a building block of nucleotides.


    11. Nucleotides
    A) are the building blocks of proteins.
    B) are involved in every chemical reaction in the cell.
    C) form physical structures such as hair.
    D) are the building blocks of DNA.


    12. A molecule composed of amino acids is
    A) a nucleotide.
    B) a lipid.
    C) a carbohydrate.
    D) a protein.


    13. An oil is a lipid that is _______ at room temperature.
    A) liquid
    B) saturated
    C) supersaturated
    D) solid


    14. ATP is a universal fuel for living organisms. The energy that ATP molecules deliver in chemical reactions is stored in
    A) covalent bonds between the molecule’s phosphate groups.
    B) covalent bonds between the molecule’s sugar and phosphate group.
    C) hydrogen bonds between the bases of two of these molecules.
    D) ionic bonds between the molecule’s sugar and base.

    15. When you place a piece of red meat on a hot barbeque, it slowly changes from soft to firm. Meat is primarily made of proteins. Which of the following might account for the change in meat texture during cooking?
    A) The heat causes the cells in the meat to produce more protein.
    B) The heat causes the chemical bonds to form between the proteins and nucleic acids in the meat.
    C) The heat from the barbeque converts proteins into lipids.
    D) The addition of heat causes proteins to lose their three-dimensional shape and link together.

    16. An atom is in its most stable state when all its electron shells are filled to capacity.
    A) True
    B) False

    17. Chemical reactions rearrange atoms but do not create or destroy them.
    A) True
    B) False


    18. A solution with a pH of 7 is neither acidic nor basic.
    A) True
    B) False

    19. Steroids and proteins are lipids.
    A) True
    B) False

  2. jcsd
  3. Feb 16, 2012 #2


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    Homework Helper
    Gold Member

    The most serious mistake is 17.

    Then look also at 5, 14, 15.

    Needs understanding, no use we tell you the answers. :smile:

    For 8 I'll give you that you can burn or oxidise glucose.
  4. Feb 16, 2012 #3


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    Staff: Mentor

    Also 4 & 6 are wrong.

    I have problem with 8 & 16.

    8 - as long as we don't know what is the reaction in question, there is more than one correct answer.

    16 is ambiguous to me.
  5. Feb 16, 2012 #4
    I'm pretty sure that 16 is correct.
  6. Feb 16, 2012 #5
    if you really feel that way about #8 tell me and why, so I can bring it up in class, and besides 5,14,15, and 17 is everything right and also 8
  7. Feb 16, 2012 #6
    and 4 & 6
  8. Feb 16, 2012 #7
    wait your certain 5 is wrong i was confident in that one
  9. Feb 16, 2012 #8


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    Science Advisor

  10. Feb 22, 2012 #9
    Just to catch you guys up I got only one wrong when corrected and the one I got wrong was 8 lol the one I honestly didn't know

    5. C
  11. Feb 22, 2012 #10
    I've no idea how you would answer question 8 as there is no chemical reaction to reference. I hope your teacher/prof had it somewhere else on the homewrok sheet.
  12. Feb 22, 2012 #11
    I will definitely bring it up in class tomorrow but that's just the question itself nothing else but i'll ask and put up what she said
  13. Feb 27, 2012 #12
    okay so it was my fault I never put the chemical up but I know how it works now basically which ever way the arrow is pointing that is the reactant
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