Modified True/False
Indicate
whether the sentence or statement is true or false. If false, change the identified word or
phrase to make the sentence or statement true.
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1.
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A
cell makes a copy of its DNA during the stage of the cell cycle called mitosis.
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2.
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In a
DNA molecule, guanine always pairs with thymine.
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3.
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Cancerous cells grow in an abnormal way.
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4.
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A
mutation is a mass of abnormal cells that develops when cancerous cells divide and grow
uncontrollably.
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5.
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Radiation is more harmful to normal cells than to cancerous
cells.
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Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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6.
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Mitosis is the stage during which a. | the cell’s nucleus divides into two new
nuclei. | b. | the cell’s DNA is replicated. | c. | the cell divides
into two new cells. | d. | the cell’s cytoplasm divides. | | |
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7.
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What
happens during cytokinesis in animal cells? a. | A new round of mitosis begins. | b. | Two new daughter
cells are formed. | c. | Each organelle divides into two
parts. | d. | A cell plate forms in the middle of the
cell. | | |
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8.
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DNA
is shaped like a a. | long, thin
rod. | b. | spiral
staircase. | c. | straight ladder. | d. | triple
helix. | | |
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9.
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During DNA replication, adenine (A) always pairs with a. | guanine
(G). | b. | cytosine
(C). | c. | thymine
(T). | d. | adenine
(A). | | |
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10.
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Cancer is a disease in which cells a. | grow and divide uncontrollably. | b. | die before they
can mature. | c. | stop producing DNA. | d. | die during
mitosis. | | |
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11.
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How
many different types of cancer are there? a. | 10 | b. | over 100 | c. | over
200 | d. | over
1,000 | | |
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12.
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Scientists think cancer begins when a. | a mutation
occurs in DNA. | b. | a cell divides too slowly. | c. | DNA replication
stops. | d. | cells stop growing. | | |
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13.
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What
is a cancer tumor? a. | a group of cells in the bloodstream | b. | a mass of normal
cells | c. | a mass of abnormal cells | d. | a mass of cells
that don’t divide | | |
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14.
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What
is chemotherapy? a. | the use of drugs
to kill cancer cells | b. | the use of surgery to remove cancer
cells | c. | the use of radiation to destroy cancer
cells | d. | the use of drugs to prevent cancer from
occurring | | |
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15.
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What
is the main cause of lung cancer? a. | water pollution | b. | air
pollution | c. | an unhealthy diet | d. | smoking | | |
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16.
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Each
rung of the DNA ladder is made of a. | a single nitrogen base. | b. | a pair of
nitrogen bases. | c. | three nitrogen bases. | d. | four nitrogen
bases. | | |
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17.
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What
is copied during replication? a. | the cell’s organelles | b. | chromosomes | c. | the cell’s DNA | d. | two daughter
cells | | |
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18.
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What
are chromatids? a. | identical
strands of chromosomes | b. | identical daughter cells | c. | doubled rods of
condensed chromatin. | d. | pigments that absorb the energy in
sunlight | | |
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19.
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What
forms around the chromatids during mitosis? a. | two new chromosomes | b. | two new
nuclei | c. | two new cells | d. | two new DNA
molecules | | |
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20.
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What
factor may lead to almost as many cancer deaths as does tobacco? a. | water
pollution | b. | an unhealthy diet | c. | air
pollution | d. | exercise | | |
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Completion
Complete each sentence or
statement.
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21.
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The
final stage of the cell cycle, during which the cytoplasm divides, is called
____________________.
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22.
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A DNA
molecule often is called a ____________________ because it twists like the threads of a
screw.
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23.
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The
sides of the DNA ladder are made of molecules of deoxyribose and ____________________.
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24.
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A
change in the DNA in a chromosome is called a(n) ____________________.
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25.
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When
a mutation disturbs the cell cycle, ____________________ can result.
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26.
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The
most common treatments for cancer include drugs, surgery, and ____________________.
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27.
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Cancer can spread when cells break off a tumor and enter the
____________________.
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28.
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A
form of treatment in which drugs destroy cancer cells is called ____________________.
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29.
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Many
cancer deaths are caused by unhealthful diets or by the use of ____________________.
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30.
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Chloroplasts contain a pigment called ____________________ that captures the energy in
light.
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