MCAT -BIOLOGICAL AND BIOCHEMICAL
FOUNDATIONS OF LIVING SYSTEMS EXAM (LATEST)
MOST RECENT EXAM 2026|2027 ACTUAL COMPLETE
REAL EXAM QUESTIONS AND CORRECTLY WELL
DEFINED ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED A+ | GUARANTEED SUCCESS!! NEWEST
EXAM | JUST RELEASED!!
Reproductive Isolation - ANSWER-This takes two forms: Pre-
zygotic and postzygotic. For pre-zygotic, Isolation may be 1.
temporal/habitat(spatial) 2. Behavioral Isolation (references
mate selection) 3. Mechanical Isolation (mating is not possible
e.g. Elephant vs mouse). 4. Gametic Isolation (fertilization of
gametes into zygote is impossible).
For Post-zygotic 1. Zygote mortality (fusion of gametes is
successful, zygote has high mortality rate, does not develop
into mature offspring).
2. Hybrid Inviability (zygote can grow into mature offspring
but offspring will have a high mortality rate and won't grow into
mature adult.
3. Hybrid sterility (offspring can grow into mature adult, but
adult cannot mate to produce offspring of its own)
,Sexually reproducing animals that are not isolated by
these barriers are
members of the same
species
Evolution - ANSWER-Evolution is how species experience
heritable (passed from one generation to the next) changes in
their traits over time.
There are 4 mechanisms of evolution (how evolution happens):
1. natural selection
2. mutation
3. genetic drift, and
4. gene flow
Amino Acids - ANSWER-Amino acids with acidic side groups
carry a net negative charge at physiologic pH.
If they have basic side groups, they carry a net positive charge
at physiologic pH.
Configurations (either relative or absolute) in amino acids
refers to the stereochemical configuration around the chiral
carbon.
Due to differences in the priority of different amino acid side
chains, not all amino acids have the same "Absolute
Configuration", which refers the R/S naming convention. Some
amino acids are R, and some are S.
However, all amino acids have the same "Relative
Configuration", which refers to the D/L naming convention. All
biologically produced amino acids are in the L configuration.
,Electrophoretic separation - ANSWER-Separation by
electrophoresis. In the
case of amino acids, electrophoretic separation depends on
the existence of a
negative net charge. So at the isoelectric point, no
separation occurs.
(*Molecular
Biology)
DNA Replication - ANSWER-Process by which DNA
copies itself
(*Molecular
Biology)
Transcription - ANSWER-The copying of
DNA into RNA
(*Molecular
Biology)
Translation - ANSWER-Synthesis of proteins
from RNA
(*Molecular Biology)
Reverse transcriptase - ANSWER-Enzyme that converts RNA to
cDNA, used by retroviruses
(*Molecular Biology)
Alpha amino acids - ANSWER-Amino acids that have an amino
group bonded directly to the alpha-carbon.
, (*Molecular Biology)
Isoelectric Point (pI) formula - ANSWER-pI = (pKa1 + pKa2)/2
Values of pI depend on side chains of amino acids which
impacts Ka1 and Ka2 values and ultimately impacts pI.
(*Molecular Biology)
Protein Structure - ANSWER-In summary, the primary structure
of a protein simply refers to the linear polypeptide with its
amino acid sequence, secondary structure is the folded version
of the linear polypeptide stabilized by hydrogen bonding,
tertiary structure is formed by the coming together of several
secondary structures that are held together by various types of
interactions, and finally a quaternary structure is formed by the
combination of several tertiary structures, again held together
via different types of interactions.
(*Molecular Biology)
Peptide bond - ANSWER-Formed by the nucleophilic addition-
elimination reaction between the carboxyl group of one amino
acid and the amino group of another amino acid. The bond is
planar and rigid, its rotation is restricted and is stabilized by
resonance delocalization of the nitrogens electrons to the
carbonyl's oxygen. peptide bond has double bond xtr thro
resonance delocalization of electrons
(*Molecular Biology)
Acid hydrolysis and proteolysis - ANSWER-Both are ways of
cleaving polypeptides. Hydrolysis is non-specific, proteolysis is
FOUNDATIONS OF LIVING SYSTEMS EXAM (LATEST)
MOST RECENT EXAM 2026|2027 ACTUAL COMPLETE
REAL EXAM QUESTIONS AND CORRECTLY WELL
DEFINED ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED A+ | GUARANTEED SUCCESS!! NEWEST
EXAM | JUST RELEASED!!
Reproductive Isolation - ANSWER-This takes two forms: Pre-
zygotic and postzygotic. For pre-zygotic, Isolation may be 1.
temporal/habitat(spatial) 2. Behavioral Isolation (references
mate selection) 3. Mechanical Isolation (mating is not possible
e.g. Elephant vs mouse). 4. Gametic Isolation (fertilization of
gametes into zygote is impossible).
For Post-zygotic 1. Zygote mortality (fusion of gametes is
successful, zygote has high mortality rate, does not develop
into mature offspring).
2. Hybrid Inviability (zygote can grow into mature offspring
but offspring will have a high mortality rate and won't grow into
mature adult.
3. Hybrid sterility (offspring can grow into mature adult, but
adult cannot mate to produce offspring of its own)
,Sexually reproducing animals that are not isolated by
these barriers are
members of the same
species
Evolution - ANSWER-Evolution is how species experience
heritable (passed from one generation to the next) changes in
their traits over time.
There are 4 mechanisms of evolution (how evolution happens):
1. natural selection
2. mutation
3. genetic drift, and
4. gene flow
Amino Acids - ANSWER-Amino acids with acidic side groups
carry a net negative charge at physiologic pH.
If they have basic side groups, they carry a net positive charge
at physiologic pH.
Configurations (either relative or absolute) in amino acids
refers to the stereochemical configuration around the chiral
carbon.
Due to differences in the priority of different amino acid side
chains, not all amino acids have the same "Absolute
Configuration", which refers the R/S naming convention. Some
amino acids are R, and some are S.
However, all amino acids have the same "Relative
Configuration", which refers to the D/L naming convention. All
biologically produced amino acids are in the L configuration.
,Electrophoretic separation - ANSWER-Separation by
electrophoresis. In the
case of amino acids, electrophoretic separation depends on
the existence of a
negative net charge. So at the isoelectric point, no
separation occurs.
(*Molecular
Biology)
DNA Replication - ANSWER-Process by which DNA
copies itself
(*Molecular
Biology)
Transcription - ANSWER-The copying of
DNA into RNA
(*Molecular
Biology)
Translation - ANSWER-Synthesis of proteins
from RNA
(*Molecular Biology)
Reverse transcriptase - ANSWER-Enzyme that converts RNA to
cDNA, used by retroviruses
(*Molecular Biology)
Alpha amino acids - ANSWER-Amino acids that have an amino
group bonded directly to the alpha-carbon.
, (*Molecular Biology)
Isoelectric Point (pI) formula - ANSWER-pI = (pKa1 + pKa2)/2
Values of pI depend on side chains of amino acids which
impacts Ka1 and Ka2 values and ultimately impacts pI.
(*Molecular Biology)
Protein Structure - ANSWER-In summary, the primary structure
of a protein simply refers to the linear polypeptide with its
amino acid sequence, secondary structure is the folded version
of the linear polypeptide stabilized by hydrogen bonding,
tertiary structure is formed by the coming together of several
secondary structures that are held together by various types of
interactions, and finally a quaternary structure is formed by the
combination of several tertiary structures, again held together
via different types of interactions.
(*Molecular Biology)
Peptide bond - ANSWER-Formed by the nucleophilic addition-
elimination reaction between the carboxyl group of one amino
acid and the amino group of another amino acid. The bond is
planar and rigid, its rotation is restricted and is stabilized by
resonance delocalization of the nitrogens electrons to the
carbonyl's oxygen. peptide bond has double bond xtr thro
resonance delocalization of electrons
(*Molecular Biology)
Acid hydrolysis and proteolysis - ANSWER-Both are ways of
cleaving polypeptides. Hydrolysis is non-specific, proteolysis is
