BIO 311C Hansen /assessment test questions with 143-
correct answers 2025//2026[GRADE A+]
What happens during G1? - ANSWER: First growth phase; cell synthesizes proteins and produces
cytoplasmic organelles
What happens during the S phase? - ANSWER: Synthesis; continues to grow as it copies
chromosomes
What happens during G2? - ANSWER: Second growth phase; cell completes preparation needed
to divide and continues basic life of the cell
What happens during mitosis? - ANSWER: Subdivided into prophase, metaphase, anaphase, and
telophase; nuclear division
What happens during cytokinesis? - ANSWER: Process of splitting the daughter cells apart;
splitting of cytoplasm and allocation of the organelles and cytoplasm into each new cell
How does the number of chromosomes compare between G1 and G2? - ANSWER: Remains the
same
How does the amount of DNA compare between G1 and G2? - ANSWER: G2 has double the
amount of DNA (after S phase where chromosomes are duplicated)
What is the outcome of mitosis and why is this important? - ANSWER: 2 diploid daughter cells;
creates more cells, regeneration, replenishes old cells when they die; essential for growth and repair
in the body
What is the difference between a kinetochore microtubule and a non-kinetochore microtubule? -
ANSWER: Kinetochore microtubules attach to the kinetochore of chromosomes whereas non-
kinetochore don't
,What is the function of a kinetochore microtubule during mitosis? - ANSWER: Where the spindle
fibers attach during division to pull chromosomes apart
What is the function of a non-kinetochore microtubule during mitosis? - ANSWER: Responsible
for elongation of cell during anaphase
Cytokinesis in animal cells - ANSWER: Formation of a cleavage furrow which gradually "pinches"
the cell in half
Cytokinesis in plant cells - ANSWER: Formation of cell plate that gradually divides the cell in half -
eventually thickens to form new cell wall
Why is cytokinesis different in plants and animals? - ANSWER: Plant cells have cell walls which
are inflexible and cannot be "pinched in"
In an experiment, you fuse two cells, making 1 large cell with 2 nuclei. At the time of fusion, Cell 1
had been in mitosis and Cell 2 had been in the G1 phase. Predict what will happen to each of the
nuclei for Cell 1 and for Cell 2 after they have fused. - ANSWER: Cell 2 nucleus will immediately
enter mitosis because the cell cycle is driven by specific signaling molecules present in the cytoplasm
and Cell 1 would continue with mitosis
What is the link between cyclins and MPF? - ANSWER: Cyclin is a regulatory protein that a kinase
must be attached to; MPF is made up of cyclin combined with a CDK (cyclin-dependent kinase)
On a molecular level, what does a MPF molecule do? - ANSWER: "Maturating-promoting factor;"
Triggers the cell's passage past the G2 checkpoint into the M phase (accumulation of cyclin proteins
combined with CDK to form MPF)
When during the cell cycle does production of cyclin really increase? - ANSWER: Accumulated
during G1 and S phase; increased during G2 prior to M phase (needs to make enough MPF to pass
G2 checkpoint and enter M phase)
What impact does a high concentration of MPF have on a cell? - ANSWER: Triggers onset of
mitosis; reduced at end of mitosis because it depends on cyclin concentration
, Interphase - ANSWER: Contains G1, S, and G2 phase; chromosomes are not visible (instead in
form of chromatin), make a copy of themselves
Prophase - ANSWER: Copies of chromosomes fasten together; nuclear membrane disappears;
chromatin condenses into chromosomes; centrosomes are pushed apart to opposite ends of the cell
nucleus by action of molecular motors acting on microtubules
Metaphase - ANSWER: Chromosomes line up along the center metaphase plate; microtubules
have found and attached to kinetochores; centromeres convene themselves on metaphase plate
equidistant from 2 centrosome poles
Anaphase - ANSWER: Chromosomes split apart and are pulled to opposite ends of the cell; break
at centromeres and sister chromatids move to opposite ends
Telophase - ANSWER: Chromosomes become hard to see (unwind into chromatin); cells splits
and 2 nuclear membranes form (2 daughter cells); nuclei reappear
List 4 external requirements for a cell to get past the G1 checkpoint - ANSWER: (1) appropriate
size
(2) adequate energy reserves (enough nucleotides to duplicate DNA)
(3) no DNA damage
(4) favorable environment
What are some ways in which a cell could divide even in the absence of the normally required
growth factor? - ANSWER: Cancer cells, for example, can have defective cell cycle control systems
and proceed past the checkpoints even in this absence; can divide indefinitely
Imagine a scenario in which a point mutation occurs in the gene for a cell cycle protein allowing the
cell to ignore the requirements to pass the G1 checkpoint. What would be a likely outcome for the
cell and surrounding tissue? - ANSWER: Cancer cells (abnormal growth and division)
Difference between benign and malignant tumor - ANSWER: Benign: abnormal cells may remain
at original site if they have too few genetic and cellular changes to survive at another site
correct answers 2025//2026[GRADE A+]
What happens during G1? - ANSWER: First growth phase; cell synthesizes proteins and produces
cytoplasmic organelles
What happens during the S phase? - ANSWER: Synthesis; continues to grow as it copies
chromosomes
What happens during G2? - ANSWER: Second growth phase; cell completes preparation needed
to divide and continues basic life of the cell
What happens during mitosis? - ANSWER: Subdivided into prophase, metaphase, anaphase, and
telophase; nuclear division
What happens during cytokinesis? - ANSWER: Process of splitting the daughter cells apart;
splitting of cytoplasm and allocation of the organelles and cytoplasm into each new cell
How does the number of chromosomes compare between G1 and G2? - ANSWER: Remains the
same
How does the amount of DNA compare between G1 and G2? - ANSWER: G2 has double the
amount of DNA (after S phase where chromosomes are duplicated)
What is the outcome of mitosis and why is this important? - ANSWER: 2 diploid daughter cells;
creates more cells, regeneration, replenishes old cells when they die; essential for growth and repair
in the body
What is the difference between a kinetochore microtubule and a non-kinetochore microtubule? -
ANSWER: Kinetochore microtubules attach to the kinetochore of chromosomes whereas non-
kinetochore don't
,What is the function of a kinetochore microtubule during mitosis? - ANSWER: Where the spindle
fibers attach during division to pull chromosomes apart
What is the function of a non-kinetochore microtubule during mitosis? - ANSWER: Responsible
for elongation of cell during anaphase
Cytokinesis in animal cells - ANSWER: Formation of a cleavage furrow which gradually "pinches"
the cell in half
Cytokinesis in plant cells - ANSWER: Formation of cell plate that gradually divides the cell in half -
eventually thickens to form new cell wall
Why is cytokinesis different in plants and animals? - ANSWER: Plant cells have cell walls which
are inflexible and cannot be "pinched in"
In an experiment, you fuse two cells, making 1 large cell with 2 nuclei. At the time of fusion, Cell 1
had been in mitosis and Cell 2 had been in the G1 phase. Predict what will happen to each of the
nuclei for Cell 1 and for Cell 2 after they have fused. - ANSWER: Cell 2 nucleus will immediately
enter mitosis because the cell cycle is driven by specific signaling molecules present in the cytoplasm
and Cell 1 would continue with mitosis
What is the link between cyclins and MPF? - ANSWER: Cyclin is a regulatory protein that a kinase
must be attached to; MPF is made up of cyclin combined with a CDK (cyclin-dependent kinase)
On a molecular level, what does a MPF molecule do? - ANSWER: "Maturating-promoting factor;"
Triggers the cell's passage past the G2 checkpoint into the M phase (accumulation of cyclin proteins
combined with CDK to form MPF)
When during the cell cycle does production of cyclin really increase? - ANSWER: Accumulated
during G1 and S phase; increased during G2 prior to M phase (needs to make enough MPF to pass
G2 checkpoint and enter M phase)
What impact does a high concentration of MPF have on a cell? - ANSWER: Triggers onset of
mitosis; reduced at end of mitosis because it depends on cyclin concentration
, Interphase - ANSWER: Contains G1, S, and G2 phase; chromosomes are not visible (instead in
form of chromatin), make a copy of themselves
Prophase - ANSWER: Copies of chromosomes fasten together; nuclear membrane disappears;
chromatin condenses into chromosomes; centrosomes are pushed apart to opposite ends of the cell
nucleus by action of molecular motors acting on microtubules
Metaphase - ANSWER: Chromosomes line up along the center metaphase plate; microtubules
have found and attached to kinetochores; centromeres convene themselves on metaphase plate
equidistant from 2 centrosome poles
Anaphase - ANSWER: Chromosomes split apart and are pulled to opposite ends of the cell; break
at centromeres and sister chromatids move to opposite ends
Telophase - ANSWER: Chromosomes become hard to see (unwind into chromatin); cells splits
and 2 nuclear membranes form (2 daughter cells); nuclei reappear
List 4 external requirements for a cell to get past the G1 checkpoint - ANSWER: (1) appropriate
size
(2) adequate energy reserves (enough nucleotides to duplicate DNA)
(3) no DNA damage
(4) favorable environment
What are some ways in which a cell could divide even in the absence of the normally required
growth factor? - ANSWER: Cancer cells, for example, can have defective cell cycle control systems
and proceed past the checkpoints even in this absence; can divide indefinitely
Imagine a scenario in which a point mutation occurs in the gene for a cell cycle protein allowing the
cell to ignore the requirements to pass the G1 checkpoint. What would be a likely outcome for the
cell and surrounding tissue? - ANSWER: Cancer cells (abnormal growth and division)
Difference between benign and malignant tumor - ANSWER: Benign: abnormal cells may remain
at original site if they have too few genetic and cellular changes to survive at another site
