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  • Genetics Question - Linked Genes (WILL AWARD BEST ANSWER!)?

    The allele for freckles (F) is dominant over the allele for no freckles

    (f). The allele for brown hair (B) is dominant over the allele for red

    hair (b). These two genes are closely linked on the same

    chromosome.

    If Ron (who comes from a pure-breeding population of

    red-haired and freckled people) mates with Hermione (who has

    brown hair and no freckles, but whose mother had red hair), what’s

    the probability that their first child will have brown hair and freckles?

    **The answer is 1/2, but I don't understand why.

    3 AnswersBiology4 years ago
  • Large Intestine Q - WILL AWARD BEST ANSWER!?

    True or false:

    In humans, the colon is responsible for absorbing water from food; without the colon, water from food must be replaced by water from drinking

    3 AnswersBiology4 years ago
  • Freshwater Fish VS Saltwater Tank - WILL AWARD BEST ANSWER!?

    What would happen if you placed a trout (freshwater fish) into a saltwater tank at the aquarium and made some observations?

    (a) The fish would lose water initially, but could reverse the direction of Cl- ion movement to deal with excess water.

    (b)The fish would take on water quickly and get bloated.

    (c)The fish would take on water initially, but could reverse the direction of Cl- ion movement to deal with excess water.

    (d)The fish would lose water and look wrinkled.

    2 AnswersFish4 years ago
  • Amino Acids - WILL AWARD BEST ANSWER!?

    The bond present between the amino acids Pro and Glu (in a red blood cell) is a(n) __________ bond. The machinery that synthesized this bond was a(n) protein _____________.

    (a) Peptide; Ribosome

    (b) Hydrogen; RNA polymerase

    (c) Peptide; Translation factor

    (d) Hydrogen; Translation factor

    (e) Hydrogen; Ribosome

    (f) Peptide; RNA polymerase

    2 AnswersBiology4 years ago
  • Potassium ion channels (Cell Membrane) - WILL AWARD BEST ANSWER?

    This K+ channel does NOT allow Cl- ions to pass through.

    What kinds of amino acids are likely present in the channel pore?

    2 AnswersBiology4 years ago
  • Transcription & DNA - WILL AWARD BEST ANSWER!?

    Transcription continues until:

    (a) a stop codon is encountered.

    (b) a ribosome pulls RNA polymerase off the DNA.

    (c) a terminator sequence is encountered.

    (d) all bases in the DNA are copied.

    (e) a transcription factor signals the end of the gene.

    Second Question:

    A template strand of DNA is read in the ____________ direction in order to direct synthesis of RNA in the ____________ direction.

    (a) 3'–5'; 3'–5'

    (b) 3'–5'; 5'–3'

    (c) 5'–3'; 5'–3'

    (d) 5'–3'; 3'–5'

    1 AnswerBiology4 years ago
  • DNA Sequence (Coding) - WILL AWARD BEST ANSWER!?

    The DNA sequence below (the template strand) is part of the coding region of a gene. What would be the sequence of amino acids for this portion of DNA? (the reading frame is indicated by the vertical lines; use the codon table)

    3' – ACG|ATT|CTT|TGC - 5'

    1 AnswerBiology4 years ago
  • Translation in Eukaryotes - WILL AWARD BEST ANSWER!?

    Which one of the following statements about translation in eukaryotes is incorrect?

    (a) All of these statements about translation in eukaryotes are correct.

    (b) A single processed mRNA can possess multiple separate protein coding regions.

    (c) There are untranslated regions at both the 5' end and 3' end of a processed mRNA.

    (d) An initiator codon is identified by recognizing a 5' cap structure and scanning for the first AUG triplet.

    (e) Translation continues until one of the three stop codons appears in the A site of the ribosome.

    1 AnswerBiology4 years ago
  • Double-stranded DNA - WILL AWARD BEST ANSWER!?

    Which of the following is true of normal double-stranded DNA?

    (a) The nucleotides in one strand are connected by hydrogen bonds.

    (b) A purine always forms a complementary base pair with a pyrimidine.

    (c) It is used by ribosomes for translation.

    (d) The percentage of the purine A always equals the percentage of the purine G.

    (e) A phosphate group in a nucleotide is attached to the 3′ carbon in ribose.

    1 AnswerBiology4 years ago
  • DNA & RNA - WILL AWARD BEST ANSWER!?

    Consider sequences of DNA and RNA:

    The coding strand of DNA and the RNA produced from that gene are ______; the template strand of DNA and the RNA produced from that gene are ______.

    (a) similar; complementary

    (b) complementary; complementary

    (c) similar; similar

    (d) complementary; similar

    1 AnswerBiology4 years ago
  • The Nernst Equation - WILL AWARD BEST ANSWER?

    Calculate the reduction potential (at 25°C) of the half-cell MnO4- (1.50×10^-1 M)/ Mn2+ (4.00×10^-2 M) at pH = 2.00.

    (The half-reaction is MnO4- + 8H+ + 5e- --> Mn2+ + 4H2O.)

    1 AnswerChemistry4 years ago
  • Selective Oxidation - WILL AWARD BEST ANSWER?

    The standard reduction potential for the half-reaction Sn4+ + 2e- --> Sn2+ is +0.15 V.

    Consider data from the table of standard reduction potentials for common half-reactions, in your text.

    For a galvanic cell under standard conditions, which of the following cathodic half reactions would produce, at the anode, a spontaneous oxidation of Sn to Sn2+ but not Sn2+ to Sn4+.

    (1) 2H+ + 2e- --> H2

    (2) Pb2+ + 2e- --> Pb

    (3) Sn4+ + 2e- --> Sn2+

    (4) 2H2O + 2e- --> H2 + 2OH-

    (5) Fe2+ + 2e- --> Fe

    (6) Sn2+ + 2e- --> Sn

    1 AnswerChemistry4 years ago
  • Equilibrium Constant Relationships - WILL AWARD BEST ANSWER!?

    Given the following equilibrium constants at 427°C:

    O2(g) + 4Na(l) = 2Na2O(s) K1 = 2.50×10^49

    O2(g) + 2Na(l) = 2NaO(g) K2 = 2.50×10^9

    O2(g) + 2Na(l) = Na2O2(s) K3 = 2.00×10^28

    O2(g) + Na(l) = NaO2(s) K4 = 3.33×10^13

    What would be the value of the equilibrium constant for each of the following reactions, at 427°C?

    (1) 2NaO2(s) + 2Na(l) = 2NaO(g) + Na2O2(s)

    (2) 2Na2O(s) + 2O2(g) = Na2O2(s) + 2NaO2(s)

    1 AnswerChemistry5 years ago
  • Equilibrium Concentrations - WILL AWARD BEST ANSWER!?

    At a particular temperature, K = 100 for the reaction:

    H2(g) + F2(g)= 2HF(g)

    In an experiment, at this temperature, 1.70 mol of H2 and 1.70 mol of F2 are introduced into a 1.44 L flask and allowed to react. At equilibrium, all species remain in the gas phase.

    (1) What is the equilibrium concentration (in mol/L) of H2?

    0.197 mol/L

    (2) What is the equilibrium concentration (in mol/L) of HF?

    1.97 mol/L

    (3) To the mixture above, an additional 8.50×10^-2 mol of H2 is added.

    What is the new equilbrium concentration (in mol/L) of HF?

    ***Note: The answer for #1 is 0.197 mol/L & the answer for #2 is 1.97 mol/L, I need help with #3***

    1 AnswerChemistry5 years ago
  • PLEASE HELP! Arrhenius Equation - WILL AWARD BEST ANSWER!?

    A(g) + B(g) ---> C(g)

    The rate law for the above reaction is:

    -d[A]/dt = k[A][B]

    The rate constant is 1.21×10^-5 L mol-1 s-1 at 311.0°C and 2.64×10^-3 L mol-1 s-1 at 503.0°C.

    Use the Arrhenius equation k = Ae^-Ea/RT to:

    1) Calculate the rate constant k at 383.0°C for this reaction.

    2) Calculate the pre-exponential factor A for this reaction.

    **Note: the Ea is: 1.06×10^2 kJ/mol

    PLEASE PROVIDE BOTH ANSWERS WITH CORRECT UNITS, THANK YOU :)

    1 AnswerChemistry5 years ago
  • PLEASE HELP! Arrhenius Equation - WILL AWARD BEST ANSWER!?

    A(g) + B(g) ---> C(g)

    The rate law for the above reaction is:

    -d[A]/dt = k[A][B]

    The rate constant is 1.21×10^-5 L mol-1 s-1 at 311.0°C and 2.64×10^-3 L mol-1 s-1 at 503.0°C.

    Use the Arrhenius equation k = Ae^-Ea/RT to:

    1) Calculate the rate constant k at 383.0°C for this reaction.

    2) Calculate the pre-exponential factor A for this reaction.

    **Note: the Ea is: 1.06×10^2 kJ/mol

    PLEASE PROVIDE BOTH ANSWERS WITH CORRECT UNITS, THANK YOU :)

    1 AnswerChemistry5 years ago
  • Attachment image

    Reaction Profile - 2-Step Mechanism?

    Use the diagram attached & match the letters with the following key terms:

    1) Reactants

    2) Products

    3) Energy of reaction (ΔE)

    4) Activation energy (Ea) for the overall process.

    5) The transition state which limits the overall reaction rate.

    2 AnswersChemistry5 years ago
  • Arrhenius Equation (II) - WILL AWARD BEST ANSWER!?

    A(g) + B(g) ---> C(g)

    The rate law for the above reaction is:

    -d[A]/dt = k[A][B]

    The rate constant is 1.21×10^-5 L mol-1 s-1 at 311.0°C and 2.64×10^-3 L mol-1 s-1 at 503.0°C.

    Use the Arrhenius equation k = Ae^-Ea/RT to:

    1) Calculate the rate constant k at 383.0°C for this reaction.

    2) Calculate the pre-exponential factor A for this reaction.

    **Note: the Ea is: 1.06×10^2 kJ/mol

    1 AnswerChemistry5 years ago
  • Arrhenius Equation - WILL AWARD BEST ANSWER!?

    A(g) + B(g) ---> C(g)

    The rate law for the above reaction is:

    -d[A]/dt = k[A][B]

    The rate constant is 1.21×10^-5 L mol-1 s-1 at 311.0°C and 2.64×10^-3 L mol-1 s-1 at 503.0°C.

    Use the Arrhenius equation

    k = Ae^-Ea/RT

    to:

    Calculate Ea for this reaction.

    1 AnswerChemistry5 years ago
  • Attachment image

    Reaction Profile - 2-Step Mechanism?

    Use the diagram attached & match the letters with the following key terms:

    1) Reactants

    2) Products

    3) Energy of reaction (ΔE)

    4) Activation energy (Ea) for the overall process.

    5) The transition state which limits the overall reaction rate.

    1 AnswerChemistry5 years ago