BMSC 200 Module 10 Exam Questions
and Answers
nucleotides - ANSWER-building block of nucleic acids
-contain nitrogenous base(purine or pyrimidine), ribose sugar(or deoxyribose),
phosphate group
ribose vs deoxyribose - ANSWER--for DNA 2' carbon is in a deoxy form(H instead of
OH on carbon 2)
-RNA has a ribose backbone
ribose is in a....form - ANSWER-cyclic(beta-D-ribofuranose)
nitrogenous bases - ANSWER--purine or pyrimidine
-planar and non-polar
-A,G,T,U,C
-link to C1 of ribose sugar through an N-glycosidic linkage
-on purine glycosidic linkage is to N9 of nitrogenous base
-on pyrimidine glycosidic linkage is to N1 of nitrogenous base
Purine vs. Pyrimidine - ANSWER-purine has 2 rings, pyrimidine has one
nucleotide vs nucleoside - ANSWER--differ by whether C5 is phosphorylated or not
-nucleotides have 1-3 phosphates on the 5' position(NMP, NDP, or NTP)
-nucleoTIDES ARE PHOSPHORYLATED nucleoSIDES
naming nucleotide or nucleosides - ANSWER-1. presence of nitrogenous base and
name of type(A,C,G,T,U)
2.type of sugar present(ribose or deoxyribose)
3.if nucleoside or nucleotide is present(-osine nomenclature for nucleoside, -ylate for
nucleotide)
-alternative method for naming nucleotides is to specify the location of the phosphate
groups. ex: adenosine 5'-triphosphate(ATP) instead of adenylate
phosphodiester bond - ANSWER--joining of nucleotides to form a linear nucleic
strand through 3'-5' phosphodiester linkages
-same phosphodiester bond is formed regardless of whether its DNA or RNA and
regardless of the nucleotides present
-the sugar chain that forms in response to the phosphodiester bond is the backbone
sequences of nucleotides specifies the - ANSWER-nucleic acid
nucleic acid strand is from - ANSWER-5' to 3' end
-sequences of bases is a form of linear information( DNA codon is transcribed to
mRNA codon which is then translated to protein)
, RNA structure - ANSWER--has ribose instead of deoxyribose
-has uracil instead of thymine
-is single stranded but is able to adopt a 3D shape
rRNA - ANSWER--integral part of ribosomes(around 80% of RNA in cells)
tRNA - ANSWER--carry activated a.a to ribosomes for protein synthesis(73-95
nucleotides long)
mRNA - ANSWER-code for proteins
-contain triplet codons that specify the a.a sequence of a protein
micro-RNA (miRNA) - ANSWER-short oligonucleotides (22-24 units in length) that
function in transcriptional and post-transcriptional regulation of gene expression
RNA vs DNA stability - ANSWER--2' OH group on RNA makes it more likely to
undergo hydrolysis at the phosphodiester linkage
-DNA does not have this risk=more reliable as a genetic information storage center
James Watson and Francis Crick - ANSWER-discovered the structure of DNA
rosalind franklin and maurice wilkins - ANSWER-obtained the data from x-ray
diffraction that showed DNA is a helix
DNA structure - ANSWER--two right handed double helix
-strands run opposite each other
-sugar-phosphate backbone with nitrogenous bases perpendicular to the backbone
-purines ALWAYS pair with pyrimidine for a constant diameter
specificity of bonding b/w nitrogenous bases is due to - ANSWER-hydrogen bonds
chargaff's rule - ANSWER-A+G=C+T
forces that stabilize the helix - ANSWER-1. hydrophobic effects: bury the purine and
pyrimidines in the interior of the helix
2. stacking interaction(stacked base pairs form van der waals forces)
3. hydrogen bonds(b/w base pairs)
4. charge-charge interactions(repulsion of negatively charge groups is reduced by
cations ex. Mg2+ and cationic proteins)
many proteins bind DNA is a SEQUENCE SPECIFIC form - ANSWER-ex: restriction
enzymes and transcription factors
DNA has a....groove and a...groove of unequal width - ANSWER-major(guanine-
cytosine side);minor(adenine-thymine side)
-within each groove base pairs are exposed and able to interact with other
substances
-DNA binding proteins can use these interactions to "read" a specific sequence
and Answers
nucleotides - ANSWER-building block of nucleic acids
-contain nitrogenous base(purine or pyrimidine), ribose sugar(or deoxyribose),
phosphate group
ribose vs deoxyribose - ANSWER--for DNA 2' carbon is in a deoxy form(H instead of
OH on carbon 2)
-RNA has a ribose backbone
ribose is in a....form - ANSWER-cyclic(beta-D-ribofuranose)
nitrogenous bases - ANSWER--purine or pyrimidine
-planar and non-polar
-A,G,T,U,C
-link to C1 of ribose sugar through an N-glycosidic linkage
-on purine glycosidic linkage is to N9 of nitrogenous base
-on pyrimidine glycosidic linkage is to N1 of nitrogenous base
Purine vs. Pyrimidine - ANSWER-purine has 2 rings, pyrimidine has one
nucleotide vs nucleoside - ANSWER--differ by whether C5 is phosphorylated or not
-nucleotides have 1-3 phosphates on the 5' position(NMP, NDP, or NTP)
-nucleoTIDES ARE PHOSPHORYLATED nucleoSIDES
naming nucleotide or nucleosides - ANSWER-1. presence of nitrogenous base and
name of type(A,C,G,T,U)
2.type of sugar present(ribose or deoxyribose)
3.if nucleoside or nucleotide is present(-osine nomenclature for nucleoside, -ylate for
nucleotide)
-alternative method for naming nucleotides is to specify the location of the phosphate
groups. ex: adenosine 5'-triphosphate(ATP) instead of adenylate
phosphodiester bond - ANSWER--joining of nucleotides to form a linear nucleic
strand through 3'-5' phosphodiester linkages
-same phosphodiester bond is formed regardless of whether its DNA or RNA and
regardless of the nucleotides present
-the sugar chain that forms in response to the phosphodiester bond is the backbone
sequences of nucleotides specifies the - ANSWER-nucleic acid
nucleic acid strand is from - ANSWER-5' to 3' end
-sequences of bases is a form of linear information( DNA codon is transcribed to
mRNA codon which is then translated to protein)
, RNA structure - ANSWER--has ribose instead of deoxyribose
-has uracil instead of thymine
-is single stranded but is able to adopt a 3D shape
rRNA - ANSWER--integral part of ribosomes(around 80% of RNA in cells)
tRNA - ANSWER--carry activated a.a to ribosomes for protein synthesis(73-95
nucleotides long)
mRNA - ANSWER-code for proteins
-contain triplet codons that specify the a.a sequence of a protein
micro-RNA (miRNA) - ANSWER-short oligonucleotides (22-24 units in length) that
function in transcriptional and post-transcriptional regulation of gene expression
RNA vs DNA stability - ANSWER--2' OH group on RNA makes it more likely to
undergo hydrolysis at the phosphodiester linkage
-DNA does not have this risk=more reliable as a genetic information storage center
James Watson and Francis Crick - ANSWER-discovered the structure of DNA
rosalind franklin and maurice wilkins - ANSWER-obtained the data from x-ray
diffraction that showed DNA is a helix
DNA structure - ANSWER--two right handed double helix
-strands run opposite each other
-sugar-phosphate backbone with nitrogenous bases perpendicular to the backbone
-purines ALWAYS pair with pyrimidine for a constant diameter
specificity of bonding b/w nitrogenous bases is due to - ANSWER-hydrogen bonds
chargaff's rule - ANSWER-A+G=C+T
forces that stabilize the helix - ANSWER-1. hydrophobic effects: bury the purine and
pyrimidines in the interior of the helix
2. stacking interaction(stacked base pairs form van der waals forces)
3. hydrogen bonds(b/w base pairs)
4. charge-charge interactions(repulsion of negatively charge groups is reduced by
cations ex. Mg2+ and cationic proteins)
many proteins bind DNA is a SEQUENCE SPECIFIC form - ANSWER-ex: restriction
enzymes and transcription factors
DNA has a....groove and a...groove of unequal width - ANSWER-major(guanine-
cytosine side);minor(adenine-thymine side)
-within each groove base pairs are exposed and able to interact with other
substances
-DNA binding proteins can use these interactions to "read" a specific sequence
