Download ACADEMIC BIOLOGY: READING GUIDE for Ch

ACADEMIC BIOLOGY: READING GUIDE for Ch. 10, Section 1
Name:
10.1: MENDEL’S LAWS OF HEREDITY (253-262)
1. a. Relate
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2. b. Predict
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2. Define the following words:
a. heredity
b. traits
c. genetics
d. gametes
e. fertilization
f. zygote
g. pollination
h. hybrid
i. alleles
j. dominant
k. recessive
l. phenotype
m. genotype
n. homozygous
o. heterozygous
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WHY MENDEL SUCCEEDED (pg 253)
3. Gregor Mendel lived during the _________________ ____________. He was the first
person to succeed in predicting how ___________ ______ _________________ from one
generation to the next.
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Mendel chose his subject carefully (253-254)
4. What organism did Mendel experiment with?
5. Where in the pea plant are the male and female sex organs located?
6. Read the ‘mini lab’ on page 254. What is inside of a pollen grain?
7. Study figure 10.1 on page 254 and describe how Mendel ‘crossed’ a purple pea plant and
white pea plant.
MENDEL’S MONOHYBRID CROSSES (pg 255)
8. Mendel’s first experiments are called ___________________ ____________ because mono
means _____ and the two parent plants differed from each other by a ___________
_________.
The first generation
9. Fine the sentences in the second paragraph on page 255 that describes the two parent pea
plants that Mendel crossed in the monohybrid cross discussed and describe the plants in your own
words._______________________________________________________________________________
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10. After the cross, Mendel found that all of the first generation offspring grew to be ________.
It was as if the ___________ parent had never __________.
The second generation
11. When Mendel allowed the tall plants in the first generation to self-pollinate, he found that
in the ___________ generation, the tall and short plants occurred in a ratio of about
_________ tall to _____ short.
12. In Mendel’s experiment, describe what each of the following means:
P1 generation:
F1 generation:
F2 generation:
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13. Look at Figure 10.3 on pg 256. List the seven pea plant traits that Mendel studied:
________________________
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The rule of unit factors (pg 256)
14. Mendel concluded that each organism has ______ factors that control each trait. We know
that these factors are _________ and that they exist in alternate forms called __________.
The rule of dominance (pg 256-257)
15. Mendel’s experiment with the height trait showed that the allele for short plants is
________________ to the allele for tall plants.
The law of segregation (pg 257)
16. Describe Mendel’s law of segregation:
PHENOTYPES AND GENOTYPES (258-259)
17. Label each of the following as phenotype or genotype:
TT
__________________
Short __________________
Tall
___________________
Tt
___________________
Purple __________________
Pp
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___________________
18. Label each of the following genotypes as homozygous or heterozygous:
TT __________________
Tt ___________________
pp ___________________
PP ___________________
Pp ___________________
MENDEL’S DIHYBRID CROSSES (pg 259)
19. In his dihybrid crosses, Mendel studied inheritance in peas that differed from each other in
_____ traits rather than only one.
20. In his dihybrid crosses, Mendel asked the question: will the two traits _______
______________ in the next generation or will they be inherited ____________________ of
each other?
The first generation
21. Read the paragraph on page 259 under The First Generation (in blue) then describe in your
own words the P1 generation in the dihybrid cross discussed:
22. Describe the F1 generation:
The second generation
23. Describe ratio of phenotypes Mendel found in the F2 generation:
The law of independent assortment (pg 260)
25. From his study of dihybrid crosses, Mendel developed his law of independent assortment. It
states that _______ for ____________ traits are inherited __________________ of each
other.
PUNNETT SQUARES (pg 260)
26. A Punnett square is a shorthand way of finding the _______________
___________________ of possible __________________ in the offspring of a cross.
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27. Study figure 10.7. The letters on the outside of the Punnett square represent the
_____________ that each parent can form.
28. Look at the genotypes of the offspring in figure 10.7 B. What are the phenotypes of these
offspring?
PROBABILITY (pg 261-262)
29. After reading this section, read the problem-solving lab 10.1 on page 262. Answer the ‘solve
the problem’ and ‘thinking critically’ questions:
1. Calculate the actual ratio of round seeded plants to wrinkled seeded plants by
dividing the number of round seeded plants by the number of wrinkled seeded
plants:
2. Express your answer as a ratio by writing the number from step 1 followed by a colon
and the numeral 1:
3. How does Mendel’s observed ratio compare with the expected 3:1 ratio?
4. Why did the actual and expected ratios differ?
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ACADEMIC BIOLOGY: READING GUIDE for Ch. 10, Section 2
Name:
10.2: MEIOSIS (263-271)
1. What are the three objectives of this section according to the section preview on pg 263?
2. Define the following words:
a. diploid
b. haploid
c. homologous chromosomes
d. meiosis
e. sperm
f. egg
g. sexual reproduction
h. genetic recombination
i. non-disjunction
Solving the puzzle (pg 263)
1.
What were the missing pieces of the puzzle in Mendel’s study of inheritance?
2.
The key to solving the puzzle was discovering the ______________ by which traits are
________________ to the next generation.
GENES, CHROMOSOMES, AND NUMBERS (pg 263)
3.
One chromosome can contain a ________________ or more genes.
Diploid and haploid cells (pg 263-264)
4.
How does the pairing of chromosomes in a diploid cell support Mendel’s work?
5. Gametes, which contain only one of each chromosome pair, are called ___________. How
does this support Mendel’s work?
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6.
Study table 10.1 on pg 265. The diploid (2n) number of chromosomes in humans is _____.
The haploid (n) number is _____. The diploid number of chromosomes in dogs is ______.
The haploid number is ______.
Homologous chromosomes (pg 264)
7.
What are two ways that two homologous chromosomes the same?
8. Why might two homologous chromosomes not be identical?
Why meiosis? (pg 265-266)
9.
Why is it not possible for gametes to be produced through mitosis?
10. Meiosis is a form of cell division that produces ___________ with ______ the number of
chromosomes as a parent’s body cell. This allows offspring, formed after fertilization, to
have the _______ number of chromosomes as their parents.
11. When a sperm fertilizes and egg, the resulting ____________ once again has the
____________ number of chromosomes, which in humans is ____.
12. Once a zygote is formed, it grows into a multicellular organism through the process of
____________.
THE PHASES OF MEIOSIS (pg 266-269)
13. Interphase: chromosomes are ________________.
14. Prophase 1: homologous chromosomes pair tightly, and non-sister chromatids may break
and exchange genetic material in a process known as ______________ ________.
Crossing over results in new combinations of ___________ on a chromosome.
15. Metaphase 1: Homologous chromosomes _______ ___ side by side.
16. Anaphase 1: Homologous chromosomes _______________ and move to opposite ends of
the cell.
17. Telophase 1: The cytoplasm divides into _____ new cells. Each cell has ______ the number
of chromosomes, but each chromosome is still _______________.
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The phases of Meiosis II (pg 269)
18. Prophase II: Spindle fibers attach to the ________________ in each of the ____ new cells.
19. Metaphase II: Each chromosome is pulled to the center of the cell and _______ ___
randomly at the equator.
20. Anaphase II: _________ _____________ separate and move to opposite poles of the cell.
21. Telophase II: the ___________ reform and the cytoplasm ____________.
22. At the end of meiosis II ______ __________ cells have been formed from one __________
cell.
MEIOSIS PROVIDES FOR GENETIC VARIATION (pg 269-270)
23. Figure 10.3 shows one way that meiosis provides for genetic variation in gametes through
crossing over. Figure A shows one homologous pair of chromosomes. Figure C shows the
four gametes produced, each with one chromosome from the pair. How has crossing over
changed the chromosomes in two of the gametes?
24. The way the homologous chromosomes line up during Metaphase 1 is a matter of chance
and affects the final combination of chromosomes in the gametes. Look at Figure 10.14A.
What is different about the way the two pairs of homologous chromosomes are lined up in
the cell on the top left, compared to the cell on the top right?
NONDISJUNCTION (pg 271)
25. During Anaphase 1 of meiosis 1, one chromosome from each homologous pair moves to
each pole of the cell. In ___________________, _______ chromosomes of a homologous
pair move to the same pole of the cell.
26. Describe and give an example of trisomy:
27. Describe and give an example of monosomy:
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