Midterm Examination #1 CSS 350 Intro. to Plant
Genetics
Recitation meets: M T W (circle one)
Name_______________
__
Multiple Choice (only one answer is correct). Partial Credit
Possible if supporting logic is provided.
1.
The first generation from a cross of two true-breeding lines is called:
A.
B.
C.
D.
E.
2.
A cross between an unknown and a homozygous recessive is called a :
A.
B.
C.
D.
E.
3.
testcross
dihybrid
monohybrid
backcross
controlled
What is the probability that two random pollen grains from a plant with
genotype Aa will both carry the A allele?
A.
B.
C.
D.
E.
4.
P
F1
F2
testcross
backcross
1
1/2
1/3
1/4
1/8
In some genetically engineered corn plants the dominant gene (BT)
produces a protein that is lethal to corn borers and other yield
limiting pests. It was also found that pollen carrying the BT gene can
kill Monarch butterflies. If the corn plant is homozygous for BT
(i.e. BT BT), what proportion of the pollen would carry the dominant
gene?
A.
B.
C.
D.
E.
All pollen
1/2
1/3
1/4
1/8
Page 1
Name_______________
__
5.
Suppose that in plants, smooth seeds (S) are dominant to wrinkled seeds
(s) and tall plant (T) are dominant to short plants (t). A plant that
is heterozygous for both these loci was crossed to a plant that was
short and wrinkled. What proportion of the progeny is expected to be
heterozygous for both loci?
A.
B.
C.
D.
E.
6.
In a Monohybrid cross AA X aa, how many different homozygous genotypes
can occur among the F2 offspring?
A.
B.
C.
D.
E.
7.
one
two
three
four
five
In a Dihybrid cross AAbb X aaBB, how many different genotypes can occur
in the F2 generation that are homozygous at both loci?
A.
B.
C.
D.
E.
9.
one
two
three
four
five
In a Monohybrid cross AA X aa, how many different heterozygous
genotypes can occur among the F2 progeny?
A.
B.
C.
D.
E.
8.
1/2
1/4
1/8
1/16
0
one
two
three
four
five
Among the crosses listed below, which one will give a 1/2 :1/2
genotypic frequency distribution in the F1 generation?
A.
B.
C.
D.
E.
AABB
AaBb
AaBb
AaBB
AAbb
X
X
X
X
X
aabb
AaBb
aabb
aaBB
aaBB
Page 2
Name_______________
__
10.
Among the crosses listed below which one will give a 1:1:1:1 genotypic
ratio in the F1 generation?
A.
B.
C.
D.
E.
11.
Aa
Aa
AA
AA
x
x
x
x
Aa
aa
aa
AA
1 : 2
2 : 6
2 : 4
1 : 2
both c and d
Which of the following gametic genotypes cannot be produced by a plant
with the genotype Yyrr?
A.
B.
C.
D.
E.
15.
The genotype of the embryo of the seed.
The genotype of the mother plant on which the seed is set.
The genotype of the male gamete.
Both b and c.
If all blue marbles are removed from the bag, what is the ratio of
colors for the remaining marbles?
A.
B.
C.
D.
E.
14.
aabb
AaBb
aabb
aaBB
aaBB
Mating of two plants produces a 1:1 ratio of phenotypes in the F1
progeny. The parental genotypes could be:
A.
B.
C.
D.
13.
X
X
X
X
X
What determines seed coat pigment?
A.
B.
C.
D.
12.
AABB
AaBb
AaBb
AaBB
AAbb
Yr
yr
YyRR
yR
both c and d
What is the frequency distribution for plant height in an F2 population
where plants are either dwarf or tall and the ratio of dwarf to tall is
1 : 3?
A.
B.
C.
D.
1/3
1/4
1/2
1/4
dwarf, 2/3 tall
dwarf, 3/4 tall
dwarf, 1/2 tall
dwarf, 2/4 tall
Page 3
Name_______________
__
16.
There are 2 phenotypes in the testcross progeny of a plant of unknown
genotype grown from a green, round seed. What was the genotype of the
plant?
A.
B.
C.
D.
E.
17.
An F2 plant grown from a yellow, round seed produces 4 phenotypes when
self-crossed. What was the genotype of the F2 plant?
A.
B.
C.
D.
E.
18.
embryo.
endosperm.
pericarp.
seed coat.
cotyledon.
Mendel's work with monohybrid crosses led to development of the law of:
A.
B.
C.
D.
E.
21.
two or more genes control the same trait
dominance is incomplete
one gene has no affect on phenotype
one gene affects more than one trait
none of the above
The ovule wall develops into what part of a seed?
A.
B.
C.
D.
E.
20.
YYRR
YyRR
yyRr
Yellow Round
YyRr
Pleiotropy refers to instances where
A.
B.
C.
D.
E.
19.
Green, round
Yyrr
yyRR
yyRr
yyrr
independent assortment.
heredity.
Murphy.
segregation.
gravity.
What is the ratio of homozygotes to heterozygotes among plants in the
dominant phenotypic class in the F2 of a monohybrid cross?
A.
B.
C.
D.
E.
1/3
2/3
1 :
1 :
1 :
heterozygotes, 2/3 homozygotes
homozygotes, 1/3 heterozygotes
1
3
2
Page 4
Name_______________
__
22.
Proteins are comprised of one or more chains of:
A.
B.
C.
D.
E.
23.
The functionality of proteins is derived from
A.
B.
C.
D.
24.
conservation of gene order among different species.
DNA synthesis.
similarity of the laws of the sum and the law of the product.
bad behavior.
none of the above.
2:1
3:1
1:2:1
1:1
4:1
Which of the following phenotypic F2 ratios suggests Co-Dominance?
A.
B.
C.
D.
E.
27.
sequences of bases in its gene's coding region.
sequence of its amino acids.
shape (conformation) and binding afinities.
of the above.
Which of the following phenotypic F2 ratios suggests Incomplete
Dominance?
A.
B.
C.
D.
E.
26.
the
the
its
all
Synteny is
A.
B.
C.
D.
E.
25.
nucleic acids.
base pairs.
amino bases.
amino acids.
steel.
2:1
3:1
1:2:1
1:1
4:1
If two or more forms of the same gene exist, the different forms are
called:
A.
B.
C.
D.
E.
Loci.
penetrance and expressivity.
pleiotrophic.
alleles.
dihybrid.
Page 5
Name_______________
__
28.
Changes in a gene's nucleotide sequence are called:
A.
B.
C.
D.
E.
phenotype
genotype
mutation
trait
character
True or False
T
F
29.
Embryos in the seeds created from self-pollination of an F2 plant are
considered the F3 generation.
T
F
30.
A plant with the genotype Yy is pure-breeding.
T
F
31.
A seed contains cells from two generations.
T
F
32.
Mendel's work confirmed the blending hypothesis of inheritance.
T
F
33.
The law of independent assortment disproved the law of segregation.
T
F
34.
Biological information is stored and replicated in the form of RNA.
T
F
35.
All DNA in a cell encodes for proteins.
Fill in the Blank or provide answer.
36.
In corn liguleless, (l) is recessive to ligules (L) and Green leaf (G)
is dominant to the normal non-green (g). If a plant that is homozygous
for liguleless and Green leaf is crossed to a plant that is homozygous
for both non-green with ligules, predict the phenotypes and genotypes
of the F1.
37.
In pecans, the outer shell may be thick (T) or thin (t). The shell of
pecans is the pericarp, which forms from the ovary wall. If you use the
pollen from a homozygous thick shell to pollinate a tree with the thin
shell phenotype, what shell phenotype would form on the tree following
the cross?
Page 6
Name_______________
__
38.
What do we call a cross where both the egg and the pollen come from the
same plant? _______________________
39.
_______________________ is a Mendelian law that states both alleles
must separate during gamete formation.
40.
_________ is the dominant phenotype.
41.
The red plant in the described cross was homozygous / heterozygous
(circle one).
42.
If a population of 500 plants has 100 tall plants and 400 dwarf plants,
what is the ratio of tall to dwarf plants?
43.
____________ refers to a physical position on a chromosome.
44.
What is the ratio of marble colors?
45.
What is the frequency distribution of marble colors?
46.
The cell formed when an egg fuses with a sperm is called a
_____________?
47.
List the genotypic frequencies for gametes produced by a plant that is
heterozygous for the Y and R loci.
Page 7
Name_______________
__
48.
Write the phenotypic frequency distribution for the F2 from the
Dihybrid cross YYrr x yyRR.
49.
GMO is an acronym (i.e., it stands for) ____________________.
50.
G. Mendel did his work in the ___________ century.
Page 8
Answer Key for Test "01_exam1b.tst", 2/21/01
Midterm Examination #1 CSS 350 Intro. to Plant
Genetics
Recitation meets: M T W (circle one)
Name_______________
__
No. in
Q-Bank
No. on
Test Correct Answer
Multiple Choice (only one answer is correct). Partial Credit
Possible if supporting logic is provided.
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
2.CHPT2
2.CHPT2
2.CHPT2
2.CHPT2
1
2
3
4
5
6
7
8
10
11
16
17
25
26
30
31
32
33
35
38
39
46
47
49
1
2
3
4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
B
A
D
A
B
B
A
D
D
C
C
B
E
E
B
D
E
D
D
D
E
D
D
A
C
C
D
C
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
27
28
36
37
43
44
45
29
30
31
32
33
34
35
T
F
T
F
F
F
F
1.CHPT1
12
36
Genotype
LlGg
1.CHPT1
13
37
1.CHPT1
1.CHPT1
14
15
38
39
Phenotype
thin
Self Fertilization or self crossing or self pollination
Law of Segregation
True or False
Fill in the Blank or provide answer.
Phenotype
Ligules/Green
Page 1
Answer Key for Test "01_exam1b.tst", 2/21/01
Name_______________
__
No. in
Q-Bank
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
1.CHPT1
19
20
21
22
23
24
No. on
Test
40
41
42
43
44
45
1.CHPT1
1.CHPT1
1.CHPT1
34
40
42
46
47
48
1.CHPT1
1.CHPT1
48
50
49
50
Correct Answer
red
heterozygous
1 : 4
locus or loci
2 : 4 : 6 , red : green : blue (ratio alone is ok)
(200,000/1,000,000 or 2/10 or 0.2): (400,000/1,000,000 or
4/10 or 0.4) : (600,000/1,000,000 or 6/10 or 0.6) red :
green ; blue (ratios alone ok)
zygote
1/4 YR, 1/4 yR, 1/4 Yr, 1/4 yr, in any order
(genotypic designation not necessary, nor the logic leading
to probabilities)
Y-R- Yellow Round prob= 3/4*3/4= 9/16
Y-rr Yellow wrinkled
prob=3/4*1/4=3/16
yyR- green Round
prob=1/4*3/4=3/16
yyrr green wrinkled
prob=1/4*1/4=1/16
genetically modified organism
19th
Page 2
Statistics for Test "01_exam1b.tst". Total questions: 50
Key Word
None
Total Difficulty Level
50 None
a
b
c
Total
32
13
4
1
None
Free Format
True or False
Multiple Choice
Matching
Total
15
7
28
0