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A Comparison of Mitosis and Meiosis
- Mitosis produces two daughter cells with the exact
same genetic material as the parent cell.^
- Meiosis produces four daughter cells, each with half
the genetic material of the parent cell.^
- In meiosis, homologous pairs of chromosomes line up
in prophase I and exchange genetic material in a
process called crossing-over.^
- Mitosis is a process of cellular division by which we
grow, maintain, and repair ourselves. Most cells of our
body undergo mitosis. Nerve and muscle cells rarely
divide, and liver cells divide only when damaged.^
- Meiosis occurs only in the gonads. Unlike the cells
produced by mitosis, meiotic cells cannot live on
their own. They must unite in fertilization in the
female- reproductive tract.^
- Cancer is uncontrolled cellular growth caused by
damaged genetic material. Cells never go into
interphase;- they divide continuously.
REVIEW QUESTIONS
- Diagram glycolysis, the first step in the biochemi-
cal decomposition of a glucose molecule. Indicate
where and how many ATP are produced.^
- Diagram the Krebs citric acid cycle, beginning with
one molecule of pyruvic acid. Indicate where and
how many ATP are produced.^
- Diagram the electron transport system with its
electron carriers. Indicate where and how many
ATP are produced.^
*4. Why are fermentation and anaerobic production of
ATP by muscle cells less efficient than glycolysis?^
*5. In addition to beer and wine, name some other
practical applications of the fermentation process
for human advancement.^
- Name the four kinds of organic bases found in a
DNA molecule, and indicate how they pair up in
linking the two helical chains of the molecule.^
Include- a linear diagrammatic drawing of a short
segment of DNA.^
7.^ Name the three main stages of the cell cycle.^
8. Name and explain what happens during the three
substages of interphase.^
*9. Why was interphase once called a “resting stage”?^
- Name and briefly describe the stages of the two
meiotic divisions of meiosis.
Chapter 4*11. Why is meiosis called a reduction division?^
*12. Compare the major differences between mitosis
and meiosis.
*Critical Thinking QuestionsTrue or False
T F 1. The breakdown of glucose requires oxygen,
because oxygen is the ultimate electron
donor for the electrons used by the cofactors
in the electron transport system.
T F 2. The anaerobic decomposition of glucose by
yeast cells yields one ATP, ethyl alcohol, CO 2 ,^
and NAD.
T F 3. Lactic acid produced in the muscles during
anaerobic respiration accumulates there and
is never broken down or ever converted to
other products.
T F 4. The formation of lactic acid regenerates NAD
for use in the glycolytic sequence.
T F 5. Each molecule of glucose undergoing
-glycolysis yields one molecule of
pyruvic acid.
T F 6. One molecule of glucose undergoing aerobic
respiration yields 34 molecules of ATP.
T F 7. The overall chemical equation for -
respiration is C 6 H 12 O 6 1 6O 2 S^ 6CO 2 1
6H 2 O 1 energy in the form of ATP.
T F 8. When nicotine adenine dinucleotide gets
reduced in electron transport, two molecules
of ATP are produced.
T F 9. Fermentation is as effective as glycolysis.
T F 10. All foods taken into the body must be broken-
down to glucose before respiration can
proceed.
Fill in the Blank
Fill in the blank with the most appropriate term.- discovered the helical (^)
-nature of the DNA molecule via X-ray crystallogra- (^)
phy studies in England. (^) - and (^)
won the Nobel Prize in 1962 for determining (^)
the three-dimensional -structure of the DNA (^)
molecule. (^) - The DNA molecule consists of a double helical (^)
chain of. (^) - In the DNA molecule, every phosphate group is (^)
bonded to a. (^) - The two types of nitrogen bases in the DNA (^)
-molecule are: , a single ring (^)