Molecular Biology Exam 1 2025
Questions and Answers 100% Pass
Which of the following can be described as the smallest living unit?
(a)DNA
(b)cell
(c)organelle
(d)protein - ✔✔B. CELL
The flow of genetic information is controlled by a series of biochemical reactions that
result in the production of
proteins, each with its own specific order of amino acids. Choose the correct series
biochemical reactions from the options presented here.
(a)replication, transcription, translation (b)replication, translation, transcription
(c)translation, transcription, replication (d)translation, replication, transcription -
✔✔(a)replication, transcription, translation
Proteins are important architectural & catalytic components within the cell, helping to
determine its chemistry, its shape, and its ability to respond to changes in the
environment. Remarkably, all of the different proteins in a cell are made from the same
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,20 __________. By linking them in different sequences, the cell can make protein
molecules with different conformations and surface chemistries, and therefore different
functions.
(a)nucleotides
(b)sugars
(c)amino acids
(d)fatty acids - ✔✔(c)amino acids
Changes in DNA sequence from one generation to the next may result in offspring that
are altered in fitness
compared with their parents. The process of change and selection over course many
generations is the basis of ____.
(a)mutation
(b)evolution
(c)heredity
(d)reproduction - ✔✔B. Evolution
Many of the mechanisms that cells use for maintenance and reproduction were first
studied at the molecular
detail in bacteria. Which bacterial species had a central role in advancing the field of
molecular biology?
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,(a)E. coli
(b)D. melanogaster
(c)S. pombe
(d)C. elegans - ✔✔a. E. coli
An ionic bond between two atoms is formed as a result of the ______________.
(a)sharing of electrons
(b)loss of a neutron from one atom
(c)loss of electrons from both atoms
(d) transfer of electrons from one atom to the other - ✔✔D. Transfer of electrons from
one atom to others
Which of the following expressions accurately describes the calculation of pH?
(a)pH = -log10[H+]
(b)pH = log10[H+]
(c)pH = -log2[H+]
(d)pH = -log10[OH-] - ✔✔(a)pH = -log10[H+]
Biological membranes are composed of specialized lipids that form bilayers. Which of
the following
is formed by unmodified fatty acids?
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, (a)fat droplets
(b)bilayers
(c)micelles
(d)planar lipid patches - ✔✔(c)micelles
Choose the answer that best fits the statement. Cholesterol is an essential component of
biological membranes. Although it is much smaller than the typical phospholipids and
glycoplipids in the membrane, it is a(n) _________ molecule, having both hydrophilic
and hydrophobic regions.
(a)polar
(b)oxygen-containing
(c)hydrophobic
(d)amphipathic - ✔✔(d)amphipathic
DNA and RNA are different. Which of the following is true of DNA but not true of
RNA?
(a)It contains uracil
(b)It contains thymine
(c)It is single stranded
(d)It has 5′-to-3′ directionality. - ✔✔(b)It contains thymine
Which of the following statements about amino acids is true?
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Questions and Answers 100% Pass
Which of the following can be described as the smallest living unit?
(a)DNA
(b)cell
(c)organelle
(d)protein - ✔✔B. CELL
The flow of genetic information is controlled by a series of biochemical reactions that
result in the production of
proteins, each with its own specific order of amino acids. Choose the correct series
biochemical reactions from the options presented here.
(a)replication, transcription, translation (b)replication, translation, transcription
(c)translation, transcription, replication (d)translation, replication, transcription -
✔✔(a)replication, transcription, translation
Proteins are important architectural & catalytic components within the cell, helping to
determine its chemistry, its shape, and its ability to respond to changes in the
environment. Remarkably, all of the different proteins in a cell are made from the same
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 1
,20 __________. By linking them in different sequences, the cell can make protein
molecules with different conformations and surface chemistries, and therefore different
functions.
(a)nucleotides
(b)sugars
(c)amino acids
(d)fatty acids - ✔✔(c)amino acids
Changes in DNA sequence from one generation to the next may result in offspring that
are altered in fitness
compared with their parents. The process of change and selection over course many
generations is the basis of ____.
(a)mutation
(b)evolution
(c)heredity
(d)reproduction - ✔✔B. Evolution
Many of the mechanisms that cells use for maintenance and reproduction were first
studied at the molecular
detail in bacteria. Which bacterial species had a central role in advancing the field of
molecular biology?
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 2
,(a)E. coli
(b)D. melanogaster
(c)S. pombe
(d)C. elegans - ✔✔a. E. coli
An ionic bond between two atoms is formed as a result of the ______________.
(a)sharing of electrons
(b)loss of a neutron from one atom
(c)loss of electrons from both atoms
(d) transfer of electrons from one atom to the other - ✔✔D. Transfer of electrons from
one atom to others
Which of the following expressions accurately describes the calculation of pH?
(a)pH = -log10[H+]
(b)pH = log10[H+]
(c)pH = -log2[H+]
(d)pH = -log10[OH-] - ✔✔(a)pH = -log10[H+]
Biological membranes are composed of specialized lipids that form bilayers. Which of
the following
is formed by unmodified fatty acids?
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 3
, (a)fat droplets
(b)bilayers
(c)micelles
(d)planar lipid patches - ✔✔(c)micelles
Choose the answer that best fits the statement. Cholesterol is an essential component of
biological membranes. Although it is much smaller than the typical phospholipids and
glycoplipids in the membrane, it is a(n) _________ molecule, having both hydrophilic
and hydrophobic regions.
(a)polar
(b)oxygen-containing
(c)hydrophobic
(d)amphipathic - ✔✔(d)amphipathic
DNA and RNA are different. Which of the following is true of DNA but not true of
RNA?
(a)It contains uracil
(b)It contains thymine
(c)It is single stranded
(d)It has 5′-to-3′ directionality. - ✔✔(b)It contains thymine
Which of the following statements about amino acids is true?
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