Biochem 301-Final Exam questions with answers

Biochem 301-Final Exam questions with |\ |\ |\ |\ |\




answers

Nucleotides composition - CORRECT ANSWERS ✔✔base, |\ |\ |\ |\ |\ |\


deoxyribose, and a phosphate |\ |\ |\




What forms the "backbone" of nucleotides? - CORRECT ANSWERS
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✔✔phosphodietsters form the polynucleotide backbone
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Nucleic acids can be... - CORRECT ANSWERS ✔✔single or double
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stranded


how do nitrogenous bases (purine and pyrimidine) pair? -
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CORRECT ANSWERS ✔✔via H bonds |\ |\ |\ |\




Nitrogenous bases (4) - CORRECT ANSWERS ✔✔Adenine, |\ |\ |\ |\ |\ |\ |\


Thymine, Cytosine, Guanine |\ |\




Number of bonds for A/T and G/C - CORRECT ANSWERS ✔✔A/T =
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2 bonds
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G/C = 3 bonds
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DNA: single or double stranded in cells? - CORRECT ANSWERS
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✔✔double stranded |\

,RNA: single or double stranded in cells? - CORRECT ANSWERS
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✔✔single stranded in cells |\ |\ |\




2 strands of DNA form... - CORRECT ANSWERS ✔✔an antiparallel,
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right handed double helix
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RNA have widely variable... - CORRECT ANSWERS ✔✔secondary
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structures


DNA: what is it? - CORRECT ANSWERS ✔✔genetic molecule of
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heredity


RNA key differences from DNA - CORRECT ANSWERS ✔✔- the
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sugar is ribose (hydroxyl group at C2' position)
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- typically single stranded
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- multifunctional: protein synthesis, gene expression, enzyme
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DNA function - CORRECT ANSWERS ✔✔- primary storage
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molecule of genetic information |\ |\ |\




- principle component of chromosomes
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RNA function - CORRECT ANSWERS ✔✔- primary information
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transfer molecule, which includes protein synthesis
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3 principal types of RNA - CORRECT ANSWERS ✔✔messanger
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RNA
transfer RNA |\

,ribosomal RNA |\




Central dogma - CORRECT ANSWERS ✔✔
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How do we know that DNA functions as the depository of genetic
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information? - CORRECT ANSWERS ✔✔genetic information can be |\ |\ |\ |\ |\ |\ |\


transferred cell to cell by using purified DNA
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Gene structure - CORRECT ANSWERS ✔✔- coding region (for the
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protein)
- control regions (timing of expression)
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what is a gene? - CORRECT ANSWERS ✔✔genetic information
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(DNA or RNA) that encodes a protein
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Ribonucleotides - CORRECT ANSWERS ✔✔A, G, U, C |\ |\ |\ |\ |\ |\ |\




what type of bond links nucleic acids? - CORRECT ANSWERS
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✔✔phosphodiester bonds |\




what structure is central to nucleic acid biochemistry? - CORRECT
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ANSWERS ✔✔heterocyclid bases of nucleosides
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How do DNA strands interact with eachother? - CORRECT
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ANSWERS ✔✔- base pairing: via H bonds |\ |\ |\ |\ |\ |\




- Base stacking: electrostatic interactions
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, double helix of DNA - CORRECT ANSWERS ✔✔two polynucleotide
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chains wrap around each other in an anti-parallel direction with
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about 10-base pairs per turn
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what is the name of naturally ocurring DNA? - CORRECT
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ANSWERS ✔✔B-DNA |\




B-DNA conformation allows proteins to.... - CORRECT ANSWERS
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✔✔contact nucleic acid bases |\ |\ |\




what occurs when the H bonds between base pairs are
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disrupted? - CORRECT ANSWERS ✔✔occurs when DNA is |\ |\ |\ |\ |\ |\ |\ |\


denatured, the covalent bonds remain intact |\ |\ |\ |\ |\




how are double-stranded DNA denatured into two polynucleotide
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strands? - CORRECT ANSWERS ✔✔- temperature
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- solution conditions (pH)
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DNA exists as a... - CORRECT ANSWERS ✔✔polynucleotide chain
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in which individual nucleotides(A, C, G, and T) are covalently
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linked by phosphodiester bonds.
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"gene" is composed of - CORRECT ANSWERS ✔✔the nucleotides
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that are decoded into protein as well as the nucleotides
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(sequences) that control gene expression |\ |\ |\ |\