BMB 252 Exam 2 Questions with Correct Answers Latest Version 2025-2026
Which phase is not part of the interphase? - Answers M
When does the cytokinesis start? - Answers Anaphase
T/F: cell can exit from the cell cycle at any stage and survive. - Answers False
The fact that all chromosomes are attached to the spindle is verified during: - Answers metaphase
checkpoint
T/F: Cyclins are kinases - Answers False
T/F: both activity and concentration of CDKs go through cyclic changes - Answers False
Phosphorylation can activate or inactivate CDK - Answers BOTH
T/F: S-cyclin is only active during the S-phase - Answers False
A CKI P27 inhibits cyclin by - Answers forming a complex with cyclin-cdk
Ubiquitin ligases cause protein degradation by - Answers marking it for degradation in proteasome
Which of the following is a ubiquitin ligase: cyclin, Cdk, a complex of APC/C and cdc20 - Answers a
complex of APC/C and cdc20
What is true: m cyclin concentration depends on the presence of the APC-cdc20, APC-cdc20 activity
depends on the concentration of the M cyclin, or both - Answers BOTH
Which are intermediate filaments: actin, desmin, myosin, neurofilament, keratin - Answers desmin,
neurofilament and keratin
Which motor protein moves mostly to the minus end - Answers dynein
Which motor protein movement is based in a ring rotation? - Answers dynein
ER is spread in the cell and not collapsed to the center because of the action of which motor protein -
Answers kinesin
Which is NOT a correct statement about microtubules: composed of tubulin, alpha tubulin can hydrolyze
ATP, beta tubulin can hydrolyze GTP or tubulin mostly gets added and dissociates at the plus end -
Answers Alpha tubulin can hydrolyze ATP
In which phase of the cell cycle do prereplicative complexes assemble on DNA? - Answers G1
T/F: phosphorylated ORC can assemble MCM on it - Answers False
Which enzyme phosphorylates ORC - Answers S-cdk
, Cdc25 removes: - Answers inhibitory phosphate on M-cdk
What does S-cdk inactivate by phosphorylation: ORC, cdc6, cdt1 or all of the above - Answers all of the
above
Which enzyme removes the inhibitory phosphate form M-cdk - Answers cdc25
M-cdk inhibitory phosphate is removed at the entrance to which phase - Answers M-phase
Chromosomes start to bind to microtubules in which phase - Answers prometaphase
What makes the sister chromatids arms stay together - Answers cohesins
T/F: In early prophase, most microtubules are shrinking to prepare to grow again to form the mitotic
spindle - Answers True
When do centrosomes duplicate - Answers S-phase
T/F: centrioles are dispensable for cell division - Answers True
What keeps the inter polar microtubules together - Answers kinesins
T/F: plus end attached to kinetochore can still add tubulin subunits - Answers True
Cohesins are destroyed in which phase - Answers anaphase
Separase is degrading cohesins by - Answers cleaving them
Poles moving apart is a movement A or B of anaphase - Answers B
Contractile ring consists of: actin, myosin, or microtubules - Answers actin and myosin
The middy contains - Answers overlapping microtubules inside the contractile ring
Mitochondria division correlates more with the stages of the cell cycle or the energy needs of the cell -
Answers the energy needs of the cell
Which cells divide by meiosis? - Answers germ cells and germ cell precursors
T/F: there is an S phase in between meiotic divisions one and two - Answers False
Two divisions of meiosis result in - Answers Four haploid cells
T/F: In metaphase II, chromosomes arms are connected all the way through their lengths - Answers
False
T/F: Bivalent can form in mitosis - Answers False
Crossovers are the result of recombination or replication? - Answers Recombination
Which phase is not part of the interphase? - Answers M
When does the cytokinesis start? - Answers Anaphase
T/F: cell can exit from the cell cycle at any stage and survive. - Answers False
The fact that all chromosomes are attached to the spindle is verified during: - Answers metaphase
checkpoint
T/F: Cyclins are kinases - Answers False
T/F: both activity and concentration of CDKs go through cyclic changes - Answers False
Phosphorylation can activate or inactivate CDK - Answers BOTH
T/F: S-cyclin is only active during the S-phase - Answers False
A CKI P27 inhibits cyclin by - Answers forming a complex with cyclin-cdk
Ubiquitin ligases cause protein degradation by - Answers marking it for degradation in proteasome
Which of the following is a ubiquitin ligase: cyclin, Cdk, a complex of APC/C and cdc20 - Answers a
complex of APC/C and cdc20
What is true: m cyclin concentration depends on the presence of the APC-cdc20, APC-cdc20 activity
depends on the concentration of the M cyclin, or both - Answers BOTH
Which are intermediate filaments: actin, desmin, myosin, neurofilament, keratin - Answers desmin,
neurofilament and keratin
Which motor protein moves mostly to the minus end - Answers dynein
Which motor protein movement is based in a ring rotation? - Answers dynein
ER is spread in the cell and not collapsed to the center because of the action of which motor protein -
Answers kinesin
Which is NOT a correct statement about microtubules: composed of tubulin, alpha tubulin can hydrolyze
ATP, beta tubulin can hydrolyze GTP or tubulin mostly gets added and dissociates at the plus end -
Answers Alpha tubulin can hydrolyze ATP
In which phase of the cell cycle do prereplicative complexes assemble on DNA? - Answers G1
T/F: phosphorylated ORC can assemble MCM on it - Answers False
Which enzyme phosphorylates ORC - Answers S-cdk
, Cdc25 removes: - Answers inhibitory phosphate on M-cdk
What does S-cdk inactivate by phosphorylation: ORC, cdc6, cdt1 or all of the above - Answers all of the
above
Which enzyme removes the inhibitory phosphate form M-cdk - Answers cdc25
M-cdk inhibitory phosphate is removed at the entrance to which phase - Answers M-phase
Chromosomes start to bind to microtubules in which phase - Answers prometaphase
What makes the sister chromatids arms stay together - Answers cohesins
T/F: In early prophase, most microtubules are shrinking to prepare to grow again to form the mitotic
spindle - Answers True
When do centrosomes duplicate - Answers S-phase
T/F: centrioles are dispensable for cell division - Answers True
What keeps the inter polar microtubules together - Answers kinesins
T/F: plus end attached to kinetochore can still add tubulin subunits - Answers True
Cohesins are destroyed in which phase - Answers anaphase
Separase is degrading cohesins by - Answers cleaving them
Poles moving apart is a movement A or B of anaphase - Answers B
Contractile ring consists of: actin, myosin, or microtubules - Answers actin and myosin
The middy contains - Answers overlapping microtubules inside the contractile ring
Mitochondria division correlates more with the stages of the cell cycle or the energy needs of the cell -
Answers the energy needs of the cell
Which cells divide by meiosis? - Answers germ cells and germ cell precursors
T/F: there is an S phase in between meiotic divisions one and two - Answers False
Two divisions of meiosis result in - Answers Four haploid cells
T/F: In metaphase II, chromosomes arms are connected all the way through their lengths - Answers
False
T/F: Bivalent can form in mitosis - Answers False
Crossovers are the result of recombination or replication? - Answers Recombination
