DREXEL BIO 209 FINAL EXAM FULLY SOLVED & UPDATED 2026
QUESTIONS WITH ACCURATE ANSWERS
weak interactions - ANSWER-electrostatic
h bonding
van der waals
hydrophobic effect- tendency of non polar molecules to avoid contact with water in aqueous
solutions
chemical bonds - ANSWER-strong- covalent ( enzymes can change them)
weak/non covalent- protein folding, membranes, transport, substrate binding
neg side chain amino acids - ANSWER-apartic acid(Asp-D)
glutamic acid (Glu-E)
positive side chain amino acids - ANSWER-Arginine(Arg-R)
Lysine (Lys-K)
Histidine (His-H)
uncharged polar side chain - ANSWER-Asparagine (Asn-N)
Glutamine (Gln-Q)
Serine (Ser-S)
Threosine (Thr-T)
Tyrosine (Tyr-Y)
nonpolar amino acids - ANSWER-alanine (ala- A)
glycine (gly-G)
valine (val-V)
leucine (leu-L)
isoleucine (ile-I)
proline (pro-P)
phenylalanine (phe-F)
,methionine (met- M)
tryptophan (trp-W)
cytesine (cys-C)
all amino acids have - ANSWER-H atom
carboxyl group
amino group
Rgroup (differentiating factor)
Linus Pauling and Robert Corey - ANSWER-X ray crystallography
- found alpha helix and beta pleated sheets (both interchain H bonding)
bonds between each amino acid - ANSWER-peptide bond
amino acid chain= polypeptide backbone
polar and nonpolar amino acids face opp sides in backbone
electrostatic interactions - ANSWER-between carboxyl and amino group of different amino acids
van der waals interactions - ANSWER-between methyl group off of side chains
alpha helix - ANSWER-tightly coiled
rod arrangement of amino acids
R-grop radiates outwards
backbone is repeating units of amino group bonded to carbonyl group
(n+4 rule)
3.6 amino acids per turn
right handed
a helix cont. - ANSWER-two or more a helices intertwine to form coiled coil (ex. keratin, fibrin,
myosin)
hemoglobin high in a helix content
chymotrypsin lacks a helix
b pleated sheet - ANSWER-forms sheet by H bonding between amino and carboxyl groups of dif
peptide chains
,parallel, antiparallel, mixed
extended polypeptide chains
levels of protein structure - ANSWER-primary- amino acid residues
secondary- alpha helix
tertiary- polypeptide chain
quaternary- assembled subunits
conservation of protein domains - ANSWER-humans and drosophilia share portions of the same
amino acid sequences
same protein domains can be found on different proteins
another name for protein assemblies - ANSWER-polymer
ex. actin filaments
covalent bonds - ANSWER-disulfide bonds help stabilize protein structure
non covalent bonds - ANSWER-mediate specificity of binding between molecules
kinetic properties of enzymes - ANSWER-increase rate of biological reaction without altering
reaction equilibria
decrease activation energy of a reaction
accelerate reactions through stabilization of transition states
the enzyme active site
enzyme active site - ANSWER-the catalytic site is 3-d
substrates bound to enzyme by electrostatic, h bonding, van der waals forces, and hydrophobic
interactions
catalytic sites form clefts crevices - ANSWER-substrate bound within cleft
water excluded
nonpolar character enhances binding of substrate
enzyme substrate complex - ANSWER-x ray crystallography, electron microscope and
spectrophotometry
enzymes derive power by bringing in favorable substrate orientation
, leonor michaelis: reaction rate increases with increasing s until vmax is achieved
saturation effect - ANSWER-ES complexes form until substrate saturation occurs at which point
no more substrate binding sites are available
reaction rates - ANSWER-enzymes increase reaction rate by decreasing activation energy
posttranslational regulation enzyme activity - ANSWER-allosteric regulation
covalent modification
proteolytic modification
allosteric regulation - ANSWER-feedback inhibition
regulates levels of synthesized end product
covalent modification - ANSWER-atp phosphorus and water involved
phosphorylation, adenylyation
uridylylation
methylation
ADP ribosylation
proteolytic modification - ANSWER-digestive enzymes
proof genetic info is stored in DNA - ANSWER-classes of biochemicals
chromosomes believed to harbor transmissible units
chromosomes have nucleic acids as well as proteins
nucleic acids are the macromolecule that carry cellular genetic material
proof genetic info is stored in DNA cont. - ANSWER-DNA is located in chromosomes, RNA
proteins are throughout cell
correlation between DNA and # of chromes
diploid org. somatic cells have 2x as germ cells (haploid)
DNA more stable than RNA
DNA composition unchanged throughout the cell, RNA and protein different in dif cell types
Frederick Griffith - ANSWER-discovery of. bacterial transformation
assay to determine that DNA is genetic material
QUESTIONS WITH ACCURATE ANSWERS
weak interactions - ANSWER-electrostatic
h bonding
van der waals
hydrophobic effect- tendency of non polar molecules to avoid contact with water in aqueous
solutions
chemical bonds - ANSWER-strong- covalent ( enzymes can change them)
weak/non covalent- protein folding, membranes, transport, substrate binding
neg side chain amino acids - ANSWER-apartic acid(Asp-D)
glutamic acid (Glu-E)
positive side chain amino acids - ANSWER-Arginine(Arg-R)
Lysine (Lys-K)
Histidine (His-H)
uncharged polar side chain - ANSWER-Asparagine (Asn-N)
Glutamine (Gln-Q)
Serine (Ser-S)
Threosine (Thr-T)
Tyrosine (Tyr-Y)
nonpolar amino acids - ANSWER-alanine (ala- A)
glycine (gly-G)
valine (val-V)
leucine (leu-L)
isoleucine (ile-I)
proline (pro-P)
phenylalanine (phe-F)
,methionine (met- M)
tryptophan (trp-W)
cytesine (cys-C)
all amino acids have - ANSWER-H atom
carboxyl group
amino group
Rgroup (differentiating factor)
Linus Pauling and Robert Corey - ANSWER-X ray crystallography
- found alpha helix and beta pleated sheets (both interchain H bonding)
bonds between each amino acid - ANSWER-peptide bond
amino acid chain= polypeptide backbone
polar and nonpolar amino acids face opp sides in backbone
electrostatic interactions - ANSWER-between carboxyl and amino group of different amino acids
van der waals interactions - ANSWER-between methyl group off of side chains
alpha helix - ANSWER-tightly coiled
rod arrangement of amino acids
R-grop radiates outwards
backbone is repeating units of amino group bonded to carbonyl group
(n+4 rule)
3.6 amino acids per turn
right handed
a helix cont. - ANSWER-two or more a helices intertwine to form coiled coil (ex. keratin, fibrin,
myosin)
hemoglobin high in a helix content
chymotrypsin lacks a helix
b pleated sheet - ANSWER-forms sheet by H bonding between amino and carboxyl groups of dif
peptide chains
,parallel, antiparallel, mixed
extended polypeptide chains
levels of protein structure - ANSWER-primary- amino acid residues
secondary- alpha helix
tertiary- polypeptide chain
quaternary- assembled subunits
conservation of protein domains - ANSWER-humans and drosophilia share portions of the same
amino acid sequences
same protein domains can be found on different proteins
another name for protein assemblies - ANSWER-polymer
ex. actin filaments
covalent bonds - ANSWER-disulfide bonds help stabilize protein structure
non covalent bonds - ANSWER-mediate specificity of binding between molecules
kinetic properties of enzymes - ANSWER-increase rate of biological reaction without altering
reaction equilibria
decrease activation energy of a reaction
accelerate reactions through stabilization of transition states
the enzyme active site
enzyme active site - ANSWER-the catalytic site is 3-d
substrates bound to enzyme by electrostatic, h bonding, van der waals forces, and hydrophobic
interactions
catalytic sites form clefts crevices - ANSWER-substrate bound within cleft
water excluded
nonpolar character enhances binding of substrate
enzyme substrate complex - ANSWER-x ray crystallography, electron microscope and
spectrophotometry
enzymes derive power by bringing in favorable substrate orientation
, leonor michaelis: reaction rate increases with increasing s until vmax is achieved
saturation effect - ANSWER-ES complexes form until substrate saturation occurs at which point
no more substrate binding sites are available
reaction rates - ANSWER-enzymes increase reaction rate by decreasing activation energy
posttranslational regulation enzyme activity - ANSWER-allosteric regulation
covalent modification
proteolytic modification
allosteric regulation - ANSWER-feedback inhibition
regulates levels of synthesized end product
covalent modification - ANSWER-atp phosphorus and water involved
phosphorylation, adenylyation
uridylylation
methylation
ADP ribosylation
proteolytic modification - ANSWER-digestive enzymes
proof genetic info is stored in DNA - ANSWER-classes of biochemicals
chromosomes believed to harbor transmissible units
chromosomes have nucleic acids as well as proteins
nucleic acids are the macromolecule that carry cellular genetic material
proof genetic info is stored in DNA cont. - ANSWER-DNA is located in chromosomes, RNA
proteins are throughout cell
correlation between DNA and # of chromes
diploid org. somatic cells have 2x as germ cells (haploid)
DNA more stable than RNA
DNA composition unchanged throughout the cell, RNA and protein different in dif cell types
Frederick Griffith - ANSWER-discovery of. bacterial transformation
assay to determine that DNA is genetic material
