BIO302 EXAMS SCRIPT 2025/2026 QUESTIONS AND
ANSWERS RATED A+
✔✔Which of the following is involved in post-transcriptional control?
A: the splicesome
B: dicer
C: RISC
D: All of the above - ✔✔All of the above
✔✔Which of the following statements about transcriptional regulators is false? -
✔✔Transcriptional regulators usually interact with the sugar-phosphate backbone on
the outside of the double helix to determine where to bind on the DNA helix
✔✔New membrane phospholipids are synthesized by enzymes bound to the_____ side
of the _____ membrane - ✔✔Cytosolic, endoplasmic reticulum
✔✔Single-particle Tracking? - ✔✔Limited mobility protein = least movement
✔✔The stimulation of auditory nerves depends on the opening and closing of channels
in the auditory hair cells. Which type of gating mechanism do these cells use? -
✔✔Stress-gated
✔✔Operons ____. - ✔✔Contain a cluster of genes transcribed as a single mRNA
✔✔Although the extracellular environment has a high sodium ion concentration and the
intracellular environment has a high potassium ion concentration, both must be
neutralized by negatively charged molecules. In the extracellular case, what is the
principal anion? - ✔✔Cl-
✔✔True or False: If the concentration of solutes inside a cell is higher than that outside,
water will in by osmosis, causing the cell to undergo crenation - ✔✔False
✔✔Which of the following statements about differentiated cells is true? - ✔✔Some of
the proteins found in differenciated cells are found in all cells of a multicellular organism
✔✔True or False: A mature miRNA assembles with a set of proteins to form a RISC
complex. RISC stands for RNA-insctructed screening complex - ✔✔False
✔✔For an uncharged molecule, the direction of passive transport across a membrane is
determined solely by ______. For a charged molecule the ____ must also be
, considered. The net driving force for a charged molecule across a membrane therefore
has two components referred to as the _______. - ✔✔Concentration
Membrane Potential
The electrochemical gradient
✔✔Both ions move in same/opposite direction - ✔✔Symport/antiport
✔✔True or False: A riboswitch is a short sequence in a number of mRNAs that change
their conformation when bound to small molecules to regulate their own transcription
and translation. - ✔✔True
✔✔Which of the following statements about the carbohydrate coating of the cell is
false?
A: It is not usually found on the cytosolic side of the membrane.
B: It can play a role in cell-cell adhesion.
C: Specific oligosaccharides can be
involved in cell-cell recognition.
D: None of the above - ✔✔D. None of the above
✔✔MicroRNA's _____.
A: Are produced from a precursor miRNA transcript
B: Can degrade RNAs by using their intrinsic catalytic activity
C: Control gene expression by base-pairing with DNA sequences
D: None of the above - ✔✔Are produced from a precursor miRNA transcript
✔✔The distinct characteristics of different cell types is a multicellular organism result
mainly from the differential regulation of the ____.
A: Replication of genes
B: Transcription of genes transcribed by RNA polymerase II
C: Transcription of housekeeping genes
D: Translation of housekeeping genes - ✔✔Transcription of genes transcribed by RNA
polymerase II
ANSWERS RATED A+
✔✔Which of the following is involved in post-transcriptional control?
A: the splicesome
B: dicer
C: RISC
D: All of the above - ✔✔All of the above
✔✔Which of the following statements about transcriptional regulators is false? -
✔✔Transcriptional regulators usually interact with the sugar-phosphate backbone on
the outside of the double helix to determine where to bind on the DNA helix
✔✔New membrane phospholipids are synthesized by enzymes bound to the_____ side
of the _____ membrane - ✔✔Cytosolic, endoplasmic reticulum
✔✔Single-particle Tracking? - ✔✔Limited mobility protein = least movement
✔✔The stimulation of auditory nerves depends on the opening and closing of channels
in the auditory hair cells. Which type of gating mechanism do these cells use? -
✔✔Stress-gated
✔✔Operons ____. - ✔✔Contain a cluster of genes transcribed as a single mRNA
✔✔Although the extracellular environment has a high sodium ion concentration and the
intracellular environment has a high potassium ion concentration, both must be
neutralized by negatively charged molecules. In the extracellular case, what is the
principal anion? - ✔✔Cl-
✔✔True or False: If the concentration of solutes inside a cell is higher than that outside,
water will in by osmosis, causing the cell to undergo crenation - ✔✔False
✔✔Which of the following statements about differentiated cells is true? - ✔✔Some of
the proteins found in differenciated cells are found in all cells of a multicellular organism
✔✔True or False: A mature miRNA assembles with a set of proteins to form a RISC
complex. RISC stands for RNA-insctructed screening complex - ✔✔False
✔✔For an uncharged molecule, the direction of passive transport across a membrane is
determined solely by ______. For a charged molecule the ____ must also be
, considered. The net driving force for a charged molecule across a membrane therefore
has two components referred to as the _______. - ✔✔Concentration
Membrane Potential
The electrochemical gradient
✔✔Both ions move in same/opposite direction - ✔✔Symport/antiport
✔✔True or False: A riboswitch is a short sequence in a number of mRNAs that change
their conformation when bound to small molecules to regulate their own transcription
and translation. - ✔✔True
✔✔Which of the following statements about the carbohydrate coating of the cell is
false?
A: It is not usually found on the cytosolic side of the membrane.
B: It can play a role in cell-cell adhesion.
C: Specific oligosaccharides can be
involved in cell-cell recognition.
D: None of the above - ✔✔D. None of the above
✔✔MicroRNA's _____.
A: Are produced from a precursor miRNA transcript
B: Can degrade RNAs by using their intrinsic catalytic activity
C: Control gene expression by base-pairing with DNA sequences
D: None of the above - ✔✔Are produced from a precursor miRNA transcript
✔✔The distinct characteristics of different cell types is a multicellular organism result
mainly from the differential regulation of the ____.
A: Replication of genes
B: Transcription of genes transcribed by RNA polymerase II
C: Transcription of housekeeping genes
D: Translation of housekeeping genes - ✔✔Transcription of genes transcribed by RNA
polymerase II
