Biochemistry Midterm Flashcards
Oxygen is one
of the elements
present in a
biomolecule. True or False?
True
One of the major
precursors in the
formation of
biomolecules are water
and carbon disulfide True or False and why?
FALSE,
“carbon disulfide” =
Carbon Dioxide
TRUE OR FALSE
Condensation is the
process of forming
macromolecules
through covalent
bonding.
FALSE,
Polymerization
TRUE OR FALSE
Supramolecular
complexes are
stabilized by
non-covalent interaction.
TRUE
TRUE OR FALSE
Eukaryotic cell
contains no
well-defined
nucleus.
FALSE,
“Eukaryotic” = Prokaryotic
TRUE OR FALSE
Prokaryotes refer
to animals and
plants.
Eukaryotes
TRUE OR FALSE
Cell is the basic unit of
life because it is where
most chemical reactions
needed to sustain life
are taking place.
TRUE
TRUE OR FALSE
Dehydration is a
condition experienced
by humans if the loss of
water in the body is
more than the intake.
TRUE
What type of
bond is prevalent
in organic
compounds?
Covalent
Ethanol, CH3CH2OH, is
an example of a:
Primary
Secondary
Tertiary
Dihydric alcohol
Primary
Which biomolecule
contains amide
group in their
structure?
Proteins
Which of the following
is NOT a property of
organic compounds?
High melting point
Low melting poin
High
Melting
point
Which atom can
possibly form 2
singles and 1
double bond?
Carbon
or C
The function group/s
present in alcohols.
Hydroxyl
Carboxyl
Carbonyl
All of the above
Hydroxyl
C-O-C is the functional
group of:
Aldehyde
Ketone
Ester
No correct answer
No correct
answer
The following are
non-polar solvents,
EXCEPT:
Water
Chloroform
Acetone
Water
Atoms form
chemical bonds
to achieve
______.
Stability
Thiols Contain:
Hydroxyl group
Carbonyl group
Carboxyl group
Sulfhydryl group
Sulfhydryl
group
Which compound is
saturated?
Ethene
Propane
Ethylene
None
None
TRUE OR FALSE
A carbon atom
can form 4 strong
ionic bonds.
FALSE
Which molecule
contains a carbon -
carbon double bond?
H2
O2
Cl2
O2
What are electrons
found in the outermost
shell which are
involved in chemical
bonding?
Valence
Electron
What is the “old
concept” about
organic
chemistry?
Vitalism
theory
A German chemist
who was able to
synthesize urea
from ammonium
cyanate
Friedrich
Wöhler
How do you call that
property of Carbon atom
in which it can bond
towards itself to form
linear, branched chain
rings?
Catenation
An ester with
a plastic
balloon odor.
Ethyl
acetate
An acid
found in
vinegar.
Acetic
acid
What thiol
compound is
added to LPG in
order to detect its
leakage?
Ethanethiol
TRUE OR FALSE
Aerobic oxidation
takes place in the
absence of
oxygen.
False
(presence of
free oxygen)
TRUE OR FALSE
Conversion of
lactic acid to
pyruvic acid is a/an
reduction reaction.
FALSE,
“reduction”
= anaerobic
TRUE OR FALSE
Oxidation to ferrous
to ferric ion is an
example of an
aerobic oxidation.
FALSE,
“aerobic” =
anaerobic
TRUE OR FALSE
Hydrolysis reaction is
the process of breaking
large molecules into
simpler forms.
TRUE
MODIFIED TRUE OR
FALSE
Transformation of
glucose into galactose is
a/an condensation
reaction.
False
(“Condensation”=
Tautomerism or
Isomeric
Transformation)
What is known
as “wood
alcohol”?
Methanol
An atom becomes
stable when its valence
shell is already occupied
with 8 electrons (refers
to what rule).
Octet
rule
Attraction formed
when electrons of
non-metals are
shared with one
another.
Covalent
bond
Electrostatic attraction
between “ions” formed
when a metal gives off
electrons for a
non-metal.
Ionic
bond
Crystalline with
high melting point;
Dissociates into
ions when
dissolved in water
Ionic
Bond
Gases, liquids, or
solid with low
melting point;
Mostly pliable,
such as plastics.
Covalent
bond
Concentration of
electron density
between the nuclei
is ___________.
Covalent
bond
Only living things
can synthesize
organic compounds
with the intervention
of _____.
Vital
force
A compound
found in
human urine.
Urea
What year did Friedrich
Wohler was able to
synthesize urea, a
compound found in human
urine, in his laboratory
using ammonium cyanate
1828
Is ammonium
cyanate an
inorganic or
organic
substance?
Inorganic
Substance
Composed of
carbon and few
other elements (H,
O, N, S, P, and
halogens)
Organic
Compounds
Composed
entirely of
covalent bonds
Organic
Compounds
May be gasses,
liquids, or
solids with low
melting points
Organic
Compounds
Mostly insoluble in
water and soluble
in non-polar
solvents
Organic
Compounds
When soluble in
water, solutions
do not conduct
electricity
Organic
Compounds
Combustible
and produces
carbon (soot)
when burned
Organic
Compounds
Chemicals
reactions are
usually very
slow
Organic
Compounds
Is the study of organic
compounds, those that
contain carbon, and other
few elements (hydrogen,
oxygen, nitrogen, sulfur,
phosphorus, and
halogens)
Organic
Chemistry
Composed of
almost all kinds
of elements
Inorganic
Compound
Mostly
ionic bonds
Inorganic
Compound
Usually solids
with high
melting point
Inorganic
Compound
Mostly soluble in
water and
insoluble in
non-polar solvents
Inorganic
Compound
Aqueous
solutions
conduct
electricity
Inorganic
Compound
Very few are
combustible and
do not form carbon
when burned
Inorganic
Compound
Chemical
reactions are
often very fast
Inorganic
Compound
Carbon can form
multiple bond
(up to how many
bonds?)
Triple
bond
Carbon can
form 4 strong
covalent bonds
Tetravalency
A carbon atom in an
organic compound
can be classified
according to its
_______________.
Degree of
substitution
Are common and
specific arrangement of
atoms that impart
predictable reactivity
and properties to a
molecule.
Functional
groups
Single bonds
from carbon
atoms, C-C
Alkane
Contains at least
one
carbon-carbon
double bond C=C
Alkene
Contains at
least one
carbon-carbon
triple bond C≡C
Alkyne
A special class of
hydrocarbon that
contains a special
type of ring.
(Benzene ring)
Arenes
It has generic
formula of R-X
where
X=Halogen
Alkyl
Halides
These compounds
contain the hydroxyl
group (-OH) to a
saturated carbon;
generic formula is R-OH
Alcohol
These compounds
contain the functional
group sulfhydryl group
(-SH); it has the generic
formula of R-SH
Thiol
The only
consumable
alcohol
Ethanol
Contains an oxygen
between an alkyl
group or phenyl ring;
It has a general
formula of R-O-R
Ethers
The nitrogen is
attached to one
1 organic
compound.
Primary
amine
It contains
an amino
group (–NH)
Aminde
Used as an
extracting agent
for organic
solvents
Ethyl
methyl
ether
Used as a
solvent to
create plastic
and dyes
Diethyl
ether
The nitrogen is
attached to one
2 organic
compounds
Secondary
amine
The nitrogen is
attached to one
3 organic
compounds
Tertiary
amine
TRUE OR FALSE
Most amines are used in
pharmaceuticals,
insecticides, paint
removers, surfactants
and rubber chemicals
TRUE
Both of these
has the
carbonyl group
(-C=O)
Aldehydes
and
Ketones
Used as an
intermediate for
perfumes and
dye
Acetaldehyde
and
Benzaldehyde
Nail polish
remove
Acetone
Used as solvent for
lacquers,
adhesives, and
cleaning materials
Ethyl
methyl
ketone
Contains
the carboxyl
group
Carboxyl
group
Smell of
pineapples
Butyric
acid
Contains the
Ester group;
R-COOR
Esters
Food
preservative
Benzoic
acid
It supports
digestive
health
Ethyl
Butyrate
The –OH in the
carboxyl group
is replaced with
a amino group
Amide
TRUE OR FALSE
Most amides are
found in proteins
and plastics
True
TRUE OR FALSE
Chemists are studying the
incorporation or derivation
of different functional
groups in a drug to ensure
that it is effective
False
TRUE OR FALSE
Knowledge of functional
groups is not that
important in research for
drug design.
False
Is the study of the
chemical substances
found in living organisms
and the chemical
interactions of these
substances with each
other
Biochemistry
Also deals with the
application of the
principles and methods
of chemistry to the fields
of biology and
physiology.
Biochemistry
It is concerned with the
physico chemical
processes underlying
digestion, absorption,
circulation, respiration,
metabolism, growth and
reproduction
Biochemistry
Processes
occurring under
normal conditions
are physiological
hence the term:
Physiological
Chemistry
Those occurring
under abnormal
conditions are
pathological. They
fall under:
Clinical
Chemistry
Is a chemical
substance
found within a
living organism
Biochemical
Chemistry
Which include
water and
inorganic salt
Bioinorganic
substance
Include
carbohydrates,
lipids, proteins,
and nucleic acid
Bioorganic
Subtances
Looks into the
relationship of the
molecular structure of
biochemical substances
to their biological
functions.
Structural
Chemistry
Studies the totality
of chemical
reactions that
occur in living
organism
Metabolism
Seeks to understand the
chemistry of the
processes and
substances that store
and transmit biological
information.
Molecular
Genetics
Aims to understand
heredity and the
expression of
genetic information
in molecular terms
Molecular
Genetics
Describes the
properties of
bioorganic substances
and their role in living
organisms.
Organic
Chemistry
Understand
disease states in
molecular terms for
proper diagnosis
and therapy.
Medicine
Understanding
metabolism and dietary
requirements as a key
component in the
maintenance of good
health.
Nutrition
The use of single-celled
organisms and viruses
in the elucidation of
many metabolic
pathways and regulatory
mechanisms
Microbiology
Understanding
mechanisms that
give a particular cell
or organism its
biochemical identity.
Genetics
The use of
organisms or their
parts to
manufacture or
modify products
Biotechnology
Investigating life
processes at the
tissue and
organism levels
Physiology
Understanding the
biochemical division
of labor within the cell
as well as the different
mechanisms involved.
Cell
Biology
These
biomolecules are
classified into 4
major division –
carbohydrates,
lipids, proteins,
and nucleic
acids
Living systems are
made up of
specialized organic
compounds known
as ________.
Biomolecule
These biomolecules is
the fact that they are
large in size, and
structurally, they
themselves are
composed of ______
Building
blocks
Are considered
to be
non-polymeric
biomolecule
Lipids
Long chains of
these building
blocks
Polymer
Main source of energy
for the body; involved
cell; plays structural
roles in plants and
some animal
Carbohydrates
long-term energy
storage of the body;
important component of
the cell membrane;
gives palatability to food
Lipids
involves in almost all
physiological processes,
such as catalysis and
transport, and has
structural functions; can
also be a source of energy
Proteins
Involved in
heredity;
responsible for the
synthesis of
proteins in the cell
Nucleotide
TRUE OR FALSE
Like any organic compounds,
biomolecules are all carbon
compounds. The prevalence of
C is due to its unparalleled
versatility in forming stable
covalent bonds through
electron-pair sharing.
TRUE
Atoms commonly found
in covalent linkage to
carbon in biomolecules
are ____, _____,
______, and ______.
Carbon itself,
hydrogen,
oxygen, and
nitrogen
TRUE OR FALSE
Hydrogen can form
one covalent bond
by contributing its
single electron.
TRUE
TRUE OR FALSE
Oxygen can
participate in three
covalent bonds
False: Oxygen
can participate
in two covalent
bonds, not three
TRUE OR FALSE
Nitrogen has three
unshared electrons
and can form three
covalent bonds.
TRUE
TRUE OR FALSE
Oxygen has two
unpaired electrons
in its outer shell.
TRUE
TRUE OR FALSE
Nitrogen
participates in two
covalent bonds.
False: Nitrogen
participates in
three covalent
bonds, not two.
TRUE OR FALSE
Carbon, nitrogen, and
oxygen can share two
electron pairs to form
double bonds with one
another.
TRUE
TRUE OR FALSE
The ability to form
double bonds enhances
the chemical versatility
of carbon, nitrogen, and
oxygen.
TRUE
TRUE OR FALSE
Carbon and oxygen
can share three
electron pairs to
form triple bonds
False: Carbon and
nitrogen can share three
electron pairs
to form triple bonds, not
carbon and oxygen.
TRUE OR FALSE
Nitrogen can form
triple bonds by
sharing three
electron pairs.
TRUE
TRUE OR FALSE
Double bonds between
carbon, nitrogen, and
oxygen are common in
biomolecules.
TRUE
The biomolecules are built according to a
structural hierarchy:
Simple molecules
are the units for
building complex
structure
TRUE OR FALSE
Organelles are
membrane-bound
cellular inclusions
dedicated to important
cellular tasks.
TRUE
TRUE OR FALSE
Metabolic processes
assimilate and transform
these inorganic precursors
through ever more
complex levels of
biomolecular order.
TRUE
All
biomolecules
start from?
Inorganic
precursors
The major precursors
for the formation of
biomolecules are ___,
____, and ____.
Water, carbon dioxide,
and three inorganic
nitrogen compounds —
ammonium(NH4+),
nitrate(NO3-) and
dinitrogen(N2).
TRUE OR FALSE
Proteins,
polysaccharides,
polynucleotides, and
lipids are all considered
polymers.
False: Proteins,
polysaccharides, and
polynucleotides are
considered polymers,
but lipids are not.
TRUE OR FALSE
Eukaryotic ribosomes
contain four different
RNA molecules and at
least 70 unique proteins.
TRUE
TRUE OR FALSE
Precursors are converted
to metabolites, which are
simple organic compounds
involved in cellular energy
transformation
TRUE
TRUE OR FALSE
The structural integrity
of supramolecular
assemblies is
maintained by co
False: The structural
integrity of supramolecular
assemblies is maintained
by noncovalent forces, not
covalent bonds.
TRUE OR FALSE
Membranes are
classified only as
supramolecular
complexes.
False: Membranes are not
classified only as
supramolecular complexes.
They share properties of both
supramolecular assemblies
and organelles.
TRUE OR FALSE
Cells are the smallest
entities capable of
displaying attributes
uniquely associated with
living organisms.
TRUE
What are the
two major
divisions of life?
Prokaryotes
and
eukaryotes.
How do you
distinguish a
prokaryotic cell
from a eukaryotic
cell?
A prokaryotic cell
has no well-defined
nucleus, whereas a
eukaryotic cell does.
What are the
partial charges in
a water molecule
represented as?
The partial positive charge
is represented as δ+ (delta
plus) for hydrogen, and the
partial negative charge is
represented as δ- (delta
minus) for oxygen.
What
organisms are
prokaryotes?
Mostly
bacteria.
What three
components are
found on the
exterior of a
prokaryotic cell?
A cell wall, an
outer membrane,
and a plasma
membrane
Healthy humans
experience intake and
loss of water everyday.
A ____ must be
maintained within the
body.
Water
Balance
If the loss of water in
the body
significantly exceeds
the intake, the body
Dehydration
What is the term used to
describe the charge
distribution in the O–H
bonds of water due to
the difference in
electronegativity?
Polar
Bonds
Which atom in a
water molecule
carries a partial
negative charge?
Oxygen
atom
If the loss of water in the
body is significantly less
the intake, the body
experiences ____ (fluid
retention in tissues).
Edema
What type of
molecule is formed
due to the
presence of polar
bonds in water?
Polar
molecule
Which bond is
mentioned as having a
small electronegativity
difference, resulting in
nonpolar
characteristics?
The C–H
bond in
hydrocarbons
TRUE OR FALSE
The oxygen atom in
a water molecule
has a partial positive
charge.
False:
(the oxygen atom
has a partial
negative charge).
TRUE OR FALSE
Polar bonds result from
a significant difference
in electronegativity
between bonded atoms.
TRUE
TRUE OR FALSE
Water is a nonpolar
molecule due to the
equal distribution of
charges.
False:
(water is a polar
molecule due to the
unequal distribution
of charges).
What type of
interaction is a
hydrogen
bond?
A
non-covalent
interaction.
Which types of
molecules can serve
as hydrogen
acceptors due to
their oxygen atoms?
Aldehydes,
ketones,
and amides.
Which functional
groups can serve
both as hydrogen
acceptors and
donors?
Alcohols,
carboxylic
acids, and
amines.
What does the
phenomenon of
life consist of?
A series of
chemical
processes
What is the
primary source of
energy liberated
by living matter?
The oxidation of
organic
substances such
as carbohydrates,
fats, and proteins.
How does
anaerobic
oxidation differ
from aerobic
oxidation?
Anaerobic oxidation
occurs in the absence of
free oxygen, whereas
aerobic oxidation occurs
in its presence.
What is
hydrolysis?
The union of a substance
with one or more
molecules of water,
breaking down large
molecules into smaller and
simpler forms
TRUE OR FALSE
The energy for all
functional activities in
living organisms comes
solely from anaerobic
oxidation.
False (most energy is
derived from the oxidation
of organic substances,
which can occur via both
aerobic and anaerobic
oxidation).
TRUE OR FALSE
Aerobic oxidation
requires the
presence of free
oxygen.
TRUE
TRUE OR FALSE
Reduction
involves the gain
of oxygen.
False (reduction
involves the loss of
oxygen or gain of
hydrogen or
electrons).
TRUE OR FALSE
Hydrolysis is an important
reaction in digestion
because it breaks down
large molecules into
smaller ones.
TRUE
TRUE OR FALSE
The oxidation of lactic
acid to pyruvic acid
occurs in the presence
of free oxygen.
False (this reaction is
typically part of anaerobic
processes, which means
by loss of electrons (gain
of valence), or absence of
presence.)
TRUE OR FALSE
All proteins contain
the elements C,H,O,
and N; most also
contain sulfur.
TRUE
The average
nitrogen content of
proteins is around
__% by mass
15.4%
An element which
is very important in
the diet of infants
and children
Phosphorous
Are organic compounds
of high molecular weight
made up of α–amino
acids joined by means
of peptide linkage.
Proteins
This means that 19
of the 20 standard
amino acids
possess a ______.
Chiral
Center
Is a protein that contains
all of the essential
amino acids in the same
relative amounts in
which the body needs
them.
Complete
dietary
protein
Does not contain
adequate amounts,
relative to the
body’s needs.
Incomplete
dietary
protein
Are two or more
incomplete dietary proteins
that when combined,
provide an adequate
amount of all essential
amino acids relative to the
body’s needs
Complentary
dietary
protein
Is an amino acid that
contains one
aminogroup, one
carboxyl group, and a
non-polarsidechain.
Non-polar
amino
acids
TRUE OR FALSE
Every amino acid
has a different
isoelectric pH.
TRUE
Mother of
all amino
acids
Alanine
Clinical
significance: it is a
substrate of SGPT
and SGOT.
Alanine
SGPT
means?
Serum glutamic
acid pyvurate
transamylase
SGOT
means?
Serum glutamic
acid oxalo
transamylase
Important to
functioning of
the nervous
system.
Valine
Are associated
with digestive
enzymes.
Leucine
and
Isoleucine
The defect on the
metabolism of val, leu and
ile will accumulate in the
tissues, perhaps because
of the absence of enzymes
and that would result to a
certain disease called ___.
Maple
Urine
Syrup
Is known
as “ helix
breaker
Proline
Does not contain a
primary amino group; N
is bonded to 2 C-atoms
( not free ); also called
as imino acid.
Proline
An essential
amino acid in
the human
system
Phenylalanine
It is important in
the utilization of
Vit.C and
production of
thyroxin
Phenylalanine
Is important in the
utilization of
B-vitamins and
synthesis of
neurotransmitters.
Tryptophan
Present in the charred
portion of broiled fish
and meat, which is
responsible for cancer
diseases.
Tryptophan
It participates in
transmethylation
reactions as methyl
donor; associated
with fat metabolism.
Methionine
It initiates
protein
synthesis
Methionine
An important
component of a
phosphoprotein;
PO4-3 group is
attached to ______.
Serine
Important in
building tissues
and utilization
of nutrient
Threonine
Needed in the
synthesis of
some thyroid
hormones
Tyrosine
It has a unique
property; found
abundant in
natural curly hair.
Cysteine
Is the simplest amino
acid; a major excitatory
neurotransmitter; used
by the body in the
detoxification of benzoic
acid
Glycine
It is optically
inactive because of
the absence of
alpha asymmetric
Carbon.
Glycine
Its salt form is
aspartate; which is
a major excitatory
neurotransmitter.
Aspartic
acid
Contains a
ß - carboxyl
group
Aspartic
acid
Contains a
gamma -
carboxyl group
Glutamic
acid
Salt form is glutamate;
a major excitatory
neurotransmitter;
MSG ( monosodium
glutamate )
Glutamic
acid
Is found in
collagen; aids in
assimilation of
other amino acids
Lysine
Contains a guanido
or guanidinium
group which imparts
basicity to the
structure
Arginine
Contains an
imidazole or
imidazolium
group
Histidine
It has significant
buffering capacity at
physiological pH; the
only amino acid
having this property
Histidine
Component
of cartilage
and skin
Collagen
Component of
skin that
provides its
elasticity
Elastin
Mechanical strength and
protective covering to
hair, fingernails,
feathers, hooves, and
etc.
Keratin
Hydrolyzes
starch to
maltose
Amylase
Hydrolyzes
lipids to
fatty
Lipase
Catalyze
reduction-oxidation
reactions
Oxidases
Bind to foreign
substances such as
bacteria or virus, to help
combat invasion of the
body by foreign
substances
Immunoglobulin
or Antibodies
Transmit signals to
coordinate biochemical
processes between
different cells, tissues,
organs
Hormones
Carries oxygen
from the lungs
to other organs
and tissues
Hemoglobin
Carries iron
from the liver to
the bone
marrow
Transferrin
Stores iron for use
in the biosynthesis
of new hemoglobin
molecules.
Ferritin
Is an oxygen storage
protein present in
muscles. It is a reserve
oxygen source for
working muscles
Myoglobin
They act as sites where
messenger molecules
bind, EXCEPT
Receptor proteins,
Channel proteins,
Glycoproteins,
Glycololueos
Glycololeus
– I made that
word up!
Are contractile
proteins
present in
muscle
Actin and
Myosin
Found in egg white
and provide
nourishment for
the developing
chick
Ovalbumin
Found in milk to
nourish and provide
immunological
protection for
mammalian young
Casein
Has one
polypeptide
chain only.
Monomeric
proteins
Made up of two or
more polypeptide
chain. Each
polypeptide chain is
a protein subunit.
Multimeric
proteins
Made up of
amino
acids only.
Simple
proteins
Has one or more
non-amino acid
component which
are called
Prosthetic Groups.
Conjugated
proteins
Exist as long
stranded molecules;
used for structural
purposes; insoluble
in water.
Fibrous
proteins
Have spherical shape;
used for non structural
purposes but have
mobile or dynamic
functions; slightly
soluble in water
Globular
proteins
Two types
of proteins:
Simple and
Conjugated
proteins
Is a chain of amino acids
that is formed when the
carboxyl group of the
α-carbon of an amino acid
reacts with the amino
group of the α-carbon of
the second amino acid.
Peptide
The bond formed in this
reaction is generally an
______. However, for
peptide proteins, the
bond is called a Peptide
Amide
bond
The formation of peptide
is clearly a type of
_______, since water is
a product after the
reaction.
Dehydration
reaction
A peptide that
contains 2
amino acids.
Dipeptide
Peptides
with 3 amino
acids.
Tripeptide
Peptides
with 4 amino
acids.
Tetrapeptide
Normally, when a
peptide has 10-20
amino acid residues
it is already referred
to as an _____.
Oligopeptide
When it contains more
than 20 amino acid
residues already it is
already referred to as
______.
Polypeptide
TRUE OR FALSE
A peptide chain has
directionality because it
has an α-amino group at
one end and an α-carboxyl
group at the other.
TRUE
TRUE OR FALSE
The N-terminal
residue of a peptide
chain has a free
α-carboxyl group
False (the
N-terminal residue
has a free α-amino
group).
There are two well–known
enkephalins are
Met-enkephalin and
Leu-enkephalin, whose
structures differ only at the
C-terminal end of the peptide;
this amino acid difference is
incorporated in their names.
Met-enkephalin:
Tyr-Gly-Gly-Phe-Met
Leu-enkephalin:
Tyr-Gly-Gly-Phe-Leu
TRUE OR FALSE
By convention, the
sequence of amino acids
in a polypeptide chain is
written starting with the
C-terminal residue.
False (it is written
starting with the
N-terminal
residue)
TRUE OR FALSE
The peptide backbone
consists of the
repeated sequence
–N–Cα–C–.
TRUE
TRUE OR FALSE
The peptide backbone is
rich in hydrogen-bonding
potential due to the
presence of carbonyl
(C=O) and NH groups.
TRUE
TRUE OR FALSE
The carbonyl group
(C=O) in the peptide
backbone is a good
hydrogen bond donor
False (the
carbonyl group
is a hydrogen
bond acceptor).
TRUE OR FALSE
Proline has an NH
group, making it a good
hydrogen bond donor
like other amino acids.
False (proline is an
exception and
does not have a
typical NH group).
TRUE OR FALSE
Hydrogen bonds between
the peptide backbone and
side chains of amino acid
residues help stabilize the
protein structure.
TRUE
What gives a
peptide chain
its
directionality?
The presence of
an α-amino group
at one end and an
α-carboxyl group
at the other.
What is the
N-terminal
residue in a
peptide chain?
The amino acid
residue with a
free α-amino
group.
C-terminal
residue in a
peptide chain?
The amino acid
residue with a
free α-carboxyl
group.
Is a pentapeptide
neurotransmitters
produced by the brain
itself that bind at
receptor sites in the
brain to reduce pain.
Enkephalins
These are two painkillers
that can bind at the same
receptor sites in the brain
as the naturally occurring
enkephalins, and thus can
reduce pain.
Morphine
and
Codeine
By convention, how
is the sequence of
amino acids in a
polypeptide chain
written?
Starting with
the N-terminal
residue.
What does the
peptide
backbone
consist of?
The repeated sequence
–N–Cα–C–, where N is the
amide nitrogen, Cα is the
α-carbon of the amino acid
residue, and the final C is
the carbonyl carbon.
What is the
hydrogen-bonding
potential of the
peptide backbone?
Each residue contains a
carbonyl group (C=O),
which is a good hydrogen
bond acceptor, and an NH
group, which is a good
hydrogen bond donor
Peptides that contain
the same kind and
number of amino
acids but differ in
order are called
Isomeric
peptides
These are peptide
hormones that are
both produced in
the pituitary gland
Oxytocin
and
Vasopressin
Which suffix does
the –yl ending
replace in amino
acids when naming
peptides?
The -ine or
–ic acid
ending
This is a tripeptide with the
sequence Glu-Cys-Gly
which is present in
significant concentrations
in most cells which serves
as an antioxidant
Glutathione
in this reaction, simple
fragments unite with
one another to form a
more complex
compound
Condensation
is the intramolecular
arrangement of atoms
within a molecule leading
to the formation of a new
substance having
distinctive properties of its
own.
Tautomerism or
Isomeric
Transformation
