Cell Cycle
Review
1. What is the correct sequence of the 5 stages
of the cell cycle?
G1  S  G2  M  C
2. Define the following terms:
a. Chromatid- duplicate half of a chromosome
b. Mitosis- division of the nucleus
c. Cell differentiation- cells increase in # and
become specialized in structure and function.
d. Cytokinesis- division of the cytoplasm
e. Centromere- a disk that attaches 2
chromatids to each other
f. cancer- doesn’t respond to normal signals that
shut down cell division
g. checkpoints- critical point where stop and go
signals regulate the cell cycle
h. diploid- 2n, chromosomes found in pairs, has 2
homologues of each chromosome
i. haploid- half the # of chromosomes
j. Crossing over- chromosomes exchange segments
of DNA
k. zygote- fertilized egg
l. Asexual reproduction- involves 1 parent
m. Sexual reproduction- joining together of 2
gametes
3. In the space provided, draw and identify the
phases of mitosis.
see FRAME
4. Describe the events that occur in each phase of
mitosis.
Prophase- nuclear membrane breaks down, spindle
fibers form
Metaphase- chromosomes align along the equator
of the cell
Anaphase- sister chromatids separate to opposite
ends of the cell
Telophase- nuclear membrane reforms, spindle
fibers disappear, cytokinesis begins
5. A typical human cell contains 46
chromosomes. After mitosis and cytokinesis,
how many chromosomes would the daughter
cells contain?
46
6. Describe the events that occur in the
interphase of the cell cycle.
G1- growth S-DNA replication G2- growth,
maturing
7. In which phase of the cell cycle does the cell
spend most of its life?
Interphase
8. Distinguish between cytokinesis in plant cells
and cytokinesis in animal cells.
Plant cells- cell wall divides cytoplasm
Animal cells- cleavage furrow divides cytoplasm
9. After which phase does cytokinesis begin?
Telophase
10. Which phase is not a part of mitosis?
Interphase
11. Mitosis ends when the daughter cell reaches
which phase?
Interphase
12. How many daughter cells are produced as a
result of mitosis? 2 and meiosis? 4
13. Name at least 2 factors that trigger cell
division.
Growth
Enzymes from other cells
14. What is the difference between benign and
malignant tumor?
Benign tumor- stays at the original site
Malignant- spreads and impairs the function of
other organs
15. Give an example of a physical factor that would
turn off cell division.
When cells are densely packed together
16. If the body’s immune system does not destroy
an abnormal cell, what will happen to that cell?
It will become a cancer cell
17. What is an example of an internal signal?
Enzymes/hormones (come from inside the cell)
18. How many chromosomes are in the body cells
of an organism that has a haploid number of 8?
16
19. DNA becomes more compact by wrapping
tightly aroudn associated proteins. Why does
this occur?
So they will fit within the cell
20. How many chromosomes exist in the human
body?
46 chromosomes
21. What is the difference in Anaphase of
mitosis, anaphase of meiosis I, and anaphase of
meiosis II?
Chromatids do not separate at the centromere
in anaphase I, they do in mitosis and meiosis II
22. The diploid number of chromosomes in a
human skin cell is 46. How many chromosomes
are in a human sperm cell?
23
23. Describe cell differentiation.
Cells not only increase in number, but become
specialized in function
24. How many sex chromosomes are in the
body? 2 How many pairs of chromosomes are in
the body? 23 pairs How many autosomes are in
the body? 44
25. Name a factor that triggers cell division.
Growth
Test:
59 Questions
*45 cell cycle (multiple choice)
*5 biochemistry (multiple choice)
*5 cells (multiple choice)
*4 short answer
In addition…
• Be able to:
– Explain why mitosis needs to produce identical
daughter cells
– Explain why reduction-division is important for
sexual reproduction
– Compare and contrast the phases of mitosis,
meiosis I and meiosis II
– Discuss cancer