Biology 30
Module 3
Assignment 12
Copyright: Ministry of Education, Saskatchewan
May be reproduced for educational purposes
Biology 30
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Assignment 12
Biology 30
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Assignment 12
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Assignment 12
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Assignment 12
Assignment 12
Values
(40)
A.
Multiple Choice: Select the best answer for each of the following and
place a check () beside it.
1.
If 50% of the offspring are tall pea plants and 50% are short pea
plants (where tall is dominant to short), the parent cross was
probably ***.
____
____
____
____
2.
4.
a.
b.
c.
d.
1/4.
1/2.
1/8.
1/16.
A plant geneticist and breeder ties bags over flowers to ***.
____
____
a.
b.
____
____
c.
d.
speed up pollination
keep flowers warm, so that they produce pollen more
quickly
keep pollen from other flowers away
encourage pollen development with increased
darkness
In sheep, white wool is dominant to black wool. If a black animal
is crossed with one which is heterozygous, the probability for a
black offspring is ***.
____
____
____
____
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Tt x Tt
Tt x tt
TT x Tt
TT x tt
If you toss a coin three times and get all heads, the chance of
getting heads on the next (fourth) toss is ***.
____
____
____
____
3.
a.
b.
c.
d.
a.
b.
c.
d.
0%.
25%.
50%.
100%.
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Assignment 12
5.
The number of possible gene combinations in the gametes of a
CcDd individual is ***.
____
____
____
____
6.
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5
10
20
40
a.
b.
c.
d.
dominant to all other plants
able to readily cross with other species
diploid
polyploid
The desirable qualities of two different wheat plant varieties could
best be united by ***.
____
____
____
____
9.
a.
b.
c.
d.
Plant geneticists frequently use a drug called colchicine to produce
individuals which are ***.
____
____
____
____
8.
1
2
4
8
If an organism has 10 chromosomes in its egg cell, the body cells
of that organism will have a number of chromosomes equal to ***.
____
____
____
____
7.
a.
b.
c.
d.
a.
b.
c.
d.
hybridization
grafting
self-pollination
inbreeding
The number of chromosomes in eggs and sperm formed by meiosis
confirms Mendel's statement that ***.
____
a.
____
b.
____
c.
____
d.
chromosome pairs are separated independently of
other pairs
a pair of factors affecting one trait is separated when
reproductive cells are formed
chromosomes are randomly divided, so that numbers
vary in different reproductive cells
all dominant factors go to one reproductive cell and all
recessive factors to another
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Assignment 12
10.
Two organisms heterozygous for a trait showing incomplete
dominance are crossed. The number of phenotypes possible in
their offspring are ***.
____
____
____
____
11.
FF
Ff
ff
any one of these
a.
b.
c.
d.
dominance
recessiveness
blending
incomplete dominance
The phenotypes of a homozygous white sheep and a heterozygous
white sheep are ***.
____
____
____
____
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a.
b.
c.
d.
In a particular cross of a tall pea plant with a short pea plant, all
the filial one generation peas are tall. This is an example of ***.
____
____
____
____
13.
1.
2.
3.
4.
In humans, free earlobes are controlled by a dominant gene F.
Attached earlobes are determined by the recessive gene f. A
woman with free earlobes married a man with attached lobes.
Their first child had attached lobes. The mother's genotype had to
be ***.
____
____
____
____
12.
a.
b.
c.
d.
a.
b.
c.
d.
gray
white
black
WW and Ww
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Assignment 12
14.
If a trait is hidden in the parents but appears in an offspring, the
trait must be due to a(n) ***.
____
____
____
____
15.
18.
transgenic cell
hybrid
vector
enzyme
a.
b.
c.
d.
easy to cross-pollinate
slow growing
all the same size
capable of being self-pollinated only, so that they
would remain pure breeding
A test cross may be used by a plant or animal breeder to ***.
____
a.
____
____
b.
c.
____
d.
determine if a particular organism is carrying a
recessive gene for a certain trait
check an organism's ability to reproduce
see if an organism can pass on hybrid vigor to its
offspring
determine the ratio of dominant to recessive genes
Genes do not normally occur in pairs in ***.
____
____
____
____
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a.
b.
c.
d.
Mendel chose garden peas not only because they differed in certain
noticeable characteristics but because they were also ***.
____
____
____
____
17.
incompletely dominant condition
dominant condition
codominant gene
recessive gene
When a bacterial plasmid transfers a fragment of DNA to a host
cell, the plasmid is acting as a(n) ***.
____
____
____
____
16.
a.
b.
c.
d.
a.
b.
c.
d.
body cells
zygotes
gametes
fertilized eggs
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Assignment 12
19.
The hereditary factors which a parent passes on to its offspring are
determined by the parent's ***.
____
____
____
____
20.
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a.
b.
c.
d.
cytoplasm
environment
phenotype
genotype
Diagram *** depicts the actual sequence of events in the formation
of recombinant DNA.
____
a.
____
b.
____
c.
____
d.
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Assignment 12
(10)
B.
Matching: In the space provided in front of each item in Column A,
write the letter of the correct answer from Column B.
Column A
____
____
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1.
2.
Column B
actual genetic composition of
an organism
cutting a DNA segment and
inserting the sections into a
“host” organism
a.
heterozygous
b.
genotype
c.
phenotype
d.
restriction enzyme
e.
gametes
____
3.
a tool in genetic manipulation
and study
____
4.
physical appearance of an
organism
f.
recombinant DNA
technology
____
5.
pairing where genes are the
same
g.
Gel Electroplhoesis
____
6.
alternative forms of a
particular gene
h.
monohybrid
i.
homozygous
____
7.
bacterial protein that can cut
both strands of DNA at a
specific nucleotide sequence
j.
alleles
____
8.
pairing of contrasting genes
____
9.
a cross where different genes
for one trait come together
____
10.
another expression used for
sex cells
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Assignment 12
C.
(4)
Short Answer
1.
Give the appropriate Mendelian principle for each of the
following…
a.
When Mendel crossed long stemmed pea plants with short
stemmed pea plants he noticed that the offspring were all
long stemmed. The principle that he formulated from this
was
b.
Mendel chose pea plants for a number of reasons.
Mendel noticed that pea plants had distinctive
characteristics and that each characteristic had an
alternative. He determined that each characteristic was
controlled by a pair of “factors”, one coming from each
parent. The principle that he formulated from this was;
c.
Crossing plants with two different traits, Mendel noticed that
the genes for one trait separated and sorted themselves into
the gametes without having any effect on the genes for the
second trait which were also separating and sorting
independently.
The principle that he formulated from these experiments was
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Assignment 12
d.
After crossing pure plants Mendel crossed the hydrid F1
generation. He noticed that the homozygous recessive trait
reappeared in the offspring.
This occurrence led Mendel to formulate the principle of
________________________________________
(2)
2.
a.
Identify what hybrid vigor is and how it develops.
b.
Each of the following represents an actual technique which
could be used for improving plants or animals, or achieving a
particular breeding objective. Summarize in your own words
what the main purpose of using each of the following
methods would be.
(2)
i.
Artificial insemination.
(2)
ii.
Cloning (Plants).
(2)
iii.
Inbreeding or line breeding.
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Assignment 12
(2)
iv.
3.
Embryo transplants.
In peas, tallness (T) is dominant over shortness (t). A plant
homozygous for tall is crossed with one which is homozygous for
short. Give the phenotypes of the following (show all your work):
(2)
a.
F1.
(2)
b.
F2.
(2)
c.
backcross of the F1 to the tall parent type?
(2)
d.
backcross of the F1 to the short parent type?
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Assignment 12
(6)
4.
In pigs, white color (W) is dominant over black color (w). Use
Punnett Squares to show the probable genotypes and phenotypes
of the offspring of the following crosses, and state these beside
each square. (Show all your work.)
a
Homozygous white pig crossed with a black pig.
genotypic ratio:
____________________
Show work
phenotypic ratio: ____________________
b.
Heterozygous white × heterozygous white.
genotypic ratio:
____________________
Show work
phenotypic ratio: ____________________
c.
Heterozygous white × black.
genotypic ratio:
____________________
Show work
phenotypic ratio: ____________________
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5.
(2)
In cattle, the polled (or naturally hornless) condition is dominant
while horned is recessive. A polled bull is bred to three cows. Cow
A, which is polled, produces a horned calf. Cow B, which is
horned, has a polled calf. Cow C, which is horned, has a horned
calf.
Bull
Genotype:
____________________
Reason for assuming that genotype:
(Give reason for each gene)
(2)
Cow A
Genotype:
____________________
Reason for assuming that genotype:
(2)
Cow B
Genotype:
____________________
Reason for assuming that genotype:
(2)
Cow C
Genotype
____________________
Reason for assuming that genotype:
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Assignment 12
(2)
6.
A cross between a black cat and a white cat resulted in an entire
litter of gray kittens.
What sort of color(s) or phenotypic ratio could be expected in
kittens from the cross of two gray cats? (Use a Punnett square to
justify your answer.)
(3)
7.
In pea plants green pod color is dominant over yellow pods and
axial flowers are dominant over terminal flowers.
A pure dominant plant is crossed with a pure recessive plant. Set
up and fill in a 4 × 4 Punnett square to show what the probabilities
are for the second filial (F2) generation. (Crossing two F1's.)
Determine the phenotypic ratio of the F2 generation.
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Assignment 12
(3)
8.
In the shorthorn breed of cattle, “red” coat color is codominant
with white coat color. A red-white gene combination produces
roan – a coat having a mixture of red hairs and white hairs.
Suppose two individuals heterozygous for both the polled and the
coat color conditions are crossed. Set up and complete a Punnett
square for this dihybrid cross. (Beside the filled in square, indicate
the phenotypic ratio.)
(4)
9.
In a particular species of dogs, dark hair is dominant over light
hair and short hair is dominant over long hair. A dog breeder
crosses an animal which is recessive for hair color and
heterozygous for hair length with another animal which is
heterozygous for hair color and homozygous dominant for hair
length.
Construct and fill in a Punnett square to show the cross between
these animals. Beside the square, identify all the possible
phenotypes of the puppies.
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Assignment 12
(2)
10.
Give an explanation for each of the following:
a.
Seeds produced from hybrid plants (such as corn, tomatoes,
etc.) which could be grown in the garden, are not usually
planted. Instead, seeds for those same hybrid strains are
obtained from commercial seed houses.
b.
It would not be possible for a beef producer to establish a
strain of pure roan shorthorn cattle that would always breed
true (for roan color).
_____
(100)
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