Adrianna Pederson
Science 30 Assignment 1.2.2 Inheritance ? ( 13 Marks)
For questions 1 to 2, read each question carefully. Decide which of the
choices BEST answers the question. Place your answer in the blank
space given.
(1 mark)
1. Which of the following is an acquired trait rather than an inherited
trait?
A.
B.
C.
D.
eye colour
blood type
colour blindness
fluency in Spanish
Answer:
D
(1 mark)
2. Consider the O, A, B, and AB blood types for humans. How many
alleles are there for the gene controlling these blood types?
A.
B.
C.
D.
1
2
3
4
Answer:
C
(3 marks)
3. Two pea plants in the parent generation each contain the
dominant allele G that codes for green pea pods and the recessive
allele g that codes for yellow pods.
Use a Punnett square to predict the probability that a plant from
the first generation will have yellow pea pods.
Answer:
GG
Gg
Gg
gg
The probably that the plant will have yellow pea pods is 25%
(1 mark)
4. Use the following information to answer the question.
A market gardener crossed a tomato plant that had yellow fruit
with one that had
red fruit. This crossing resulted in 302 seeds. When these seeds
matured into plants,
147 had yellow fruit and 155 had red fruit.
Which of the following Punnett squares represents the cross?
A.
B.
C.
D.
Answer:
B
5. The right-handed allele, R, is dominant over the left-handed allele,
r. The Punnett square representing a cross between a homozygous
left-handed male, rr, and a homozygous right-handed female, RR, is
as follows.
(1 mark)
a. Describe the left/right-handed genotype of the offspring.
Answer:
The right handed gene is the more dominant gene
(1 mark)
b. Describe the left/right-handed phenotype of the offspring.
Answer:
They are right handed
(2 marks)
6. Suppose a certain individual CANNOT roll his or her tongue.
Explain why you can conclude that this individual has two
recessive alleles for this trait.
Answer:
Because if one of them had dominant alleles for the trait then the individual would be able
to roll their tongue and recessive traits only appear when there are two recessive alleles
present.
7. In cats, the gene that causes ginger fur is carried on the X
chromosome. The allele for ginger colour, G, is dominant to the one
for black colour, g.
(3 marks)
a. Draw a sex-linked Punnett square for a ginger male cat crossed
with a black female cat.
Answer:
GG
Gg
Gg
gg
(1 mark)
b. Determine the probability of the male offspring having black fur.
Answer:
25%
(1 mark)
c. Determine the probability of the female offspring having black fur.
Answer:
75%
(1 mark)
d. Determine the probability of the female offspring being carriers of
the recessive gene for black fur.
Answer:
25%