Assignment 2 – Flashcards
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What feature of mononucleotides provides the energy needed for polymerization when nucleic acids are formed?
answer
their phosphate groups
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Starting at the 5' end, what is the base sequence of the RNA strand shown in the figure?
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UAGC
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Pair up the nucleotide bases with their complementary partners.
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Adenine-Thymine: 5N, 2 rings, 3 H/ 2 N, 2 O, 1 ring, 4 H.
Guanine-Cytosine: 5N, 1 O, 2 rings, 4 H
3N, 1 O, 1 ring, 3H
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Write the complementary sequence for the following DNA sequence, in order from 3' to 5':
5′−CGATATTGAGCTAAGCTT−3′
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3′−
GCTATAACTCGATTCGAA
−5′
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Rank the following base pairs according to their stability.
Rank from most to least stable. To rank items as equivalent, overlap them.
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most stable: 3 H connecting, 2 H connecting, 1 H connecting
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By convention, the sequence of bases in a nucleic acid is always written in which direction?
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5' → 3'
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What forms the "backbone" of a nucleic acid?
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a chain of sugar and phosphate groups, linked through phosphodiester bonds
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Hairpins and stem-and-loop patterns make up what part of RNA's structure?
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secondary
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If a strand of DNA has the nitrogen base sequence 5'-ATTTGC-3', what will be the sequence of the matching strand?
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3'-TAAACG-5'
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If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases does it contain?
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75
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The two strands of a DNA double helix are held together by _____ that form between pairs of nitrogenous bases.
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hydrogen bonds
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A nucleotide is composed of a(n) _____.
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phosphate group, a nitrogen-containing base, and a five-carbon sugar
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Sort the parts of a nucleic acid according to whether each occurs exclusively in DNA, exclusively in RNA, or in both types of nucleic acid
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Exclusively DNA: thymine, deoxyribose
Eclusively RNA: uracil, ribose
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Identify three possible components of a DNA nucleotide.
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deoxyribose, phosphate group, thymine
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The term ribozyme describes what property of RNA molecules?
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catalytic
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A nucleotide is made up of which of the following subunits?
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a 5-carbon sugar, a phosphate group, and a nitrogenous base
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Which of the following best describes DNA's secondary structure?
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double antiparallel helical strands
