Download Cell Cycle

Biology – Study Guide Answer Key
This study guide is due on B –Mon. 2/6/17, A-Fri. 2/3/17.
Chapter 10-11 (Sec 4) Test – A – Tues., 2/7/17, B – Wed. 2/8/17
When studying for this test, use your ‘do nows’, notes, homework, class handouts, and
your textbook.
Vocabulary
Cell division
Mitosis
Cytokinesis
Chromatid
Centromere
Interphase
Cell cycle
Prophase
Centriole
Spindle
Metaphase
Anaphase
Telophase
Cyclin
Cancer
homologous
diploid
haploid
meiosis
tetrad
crossing-over
Cell Growth - Chapter 10 – Section 10-1 – Pgs. 241-243
1. Give two reasons why cells divide.
1. Increase surface area-to-volume ratio.
2. Avoid DNA “overload”
2. What happens to the surface area and volume of a cell as the cell grows?
As the cell grows, the surface area to volume ratio decreases.
3. Calculate the surface area, volume, and ratio of surface area to volume of an imaginary cubic
cell measuring 3 cm on each side.
Surface area = 3cm x 3cm x 6 = 54cm2
Volume = 3cm x 3cm x 3cm = 27 cm3
Ratio: 54 cm2/27cm3 = 2:1
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Cell Division - Chapter 10 – Section 10-2 – Pgs. 244-249
Cell Cycle
Cell growth and division occur in a regular cycle. This cycle is divided into four
phases: G1, S, G2, and M. The diagram shows this cycle, along with events that
occur in each phase.
Follow the prompts below.
• Color the phase in which most cell growth occurs blue.
• Color the phase in which DNA replication occurs red.
• Color the phase in which preparation for mitosis occurs yellow.
• Color the phase in which mitosis and cytokinesis occur orange.
Use the diagram to answer the questions.
1. Which three phases make up interphase?
G1, S, G2
2. Many organelles and molecules needed for cell division are formed after DNA
replication and before mitosis. In which phase are they formed?
G2
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3. When during the cell cycle are chromosomes visible?
cell division
4. What are the phases of mitosis in order?
prophase, metaphase, anaphase, telophase
5. How does the chromosome number of daughter cells compare to the chromosome number of
parent cell after a normal mitotic cell division? Why?
The chromosome number is the same. In mitosis the chromosome number is maintained.
The diagram below shows size cells in various phases of the cell cycle. Note the cells are not
arranged in the order in which the cell cycle occurs. Use the diagram to answer questions 6-11.
6. Cells A & F show an early and a late stage of the same phase of the cell cycle. What phase it?
prophase
7. Which cell is in metaphase?
C
8. Which cell is in the first phase of M phase (mitosis)? A
9. In cell A, what structure is labeled X? centrioles
10. List the diagrams in order from first to last in the cell cycle. D, A, F, C, E, B
11. Are the cells depicted plant or animal cells? Animal cells
a. Explain your answer. Circular shape, have centrioles, and divide by a cleavage
furrow.
b. If it were the other type of cell what would be different in the diagrams?
Formation of a cell plate, no centrioles, and shape of cells would be square
12. What is the longest phase of the cell cycle? prophase
13. Why is mitosis important? Allows cells to divide
14. Predict what would happen if an individual had faulty spindle fibers.
Chromosomes wouldn’t separate properly and Daughter cells would end up with the
wrong number of chromosomes
15. Predict what would happen if cytokinesis was skipped.
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Cells would have too many chromosomes; cells wouldn’t function properly because
they would be too big.
Regulating the Cell Cycle - Chapter 10 – Section 10-3 – Pgs. 250-252
1. What is cancer?
A disorder in which some of the body’s own cells lose the ability to control growth.
2. What is a tumor?
Masses of cells that can cause damage to the surrounding tissues.
When cells come in contact with one another, molecules on their surfaces signal them to
stop growing. This prevents cells from growing uncontrollably and disrupting nearby
tissues.
3. Circle the dish(es) in which cells would be stimulated to grow.
4. Mark an X over the dish(es) in which cells would not be growing.
5. What happens when there is a gap between two groups of cells?
Cells begin to grow until they come in to contact with each other.
6. Which of the following best describes cancer? (Circle one)
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Uncontrolled cell growth
Cells stop growing
Meiosis - Chapter 11 – Section 11-4 – Pgs. 275-278
Figure 11-5
1. What is shown in Figure 11-5?
crossing over
2. What is a gamete?
specialized cell involved in sexual reproduction.
3. Define the following:
a. Diploid (2N) contains two sets of chromosomes.
b. Haploid (N) contains one set of chromosomes.
c. Tetrad – a structure formed in prophase I of meiosis in which a
chromosome pairs with its corresponding homologous chromosome.
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4. Compare and contrast mitosis and meiosis.
5. Phases of Meiosis
Name of Phase
Description
1.prophase I
Homologous chromosomes pair up and form tetrad
2.anaphase I
Spindle fibers move homologous chromosomes to opposite sides
3.telophase II
Nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed
4.metaphase II
Chromosomes line up along equator, not in homologous pairs
5.prophase I
Crossing-over occurs
6.anaphase II
Chromatids separate
7.metaphase I
Homologs line up along equator
8.telophase I
Cytoplasm divides, 2 daughter cells are formed
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