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dihybrids and pedigrees

Total questions: 28

Worksheet time: 1hrs 17mins

Name
Class
Date
1.
In a dihybrid cross
a)
one trait is crossed.
b)
two traits are crossed.
c)
four boxes are needed for the punnett square.
d)
mom's alleles are dominant.
2.

What is the genotype for a pea plant homozygous for round seeds (R), and heterozygous for yellow seeds (Y)?

a)

RrYy

b)

RRyy

c)

RRYy

d)

rryy

3.
What gamete possibilities could come from this parent's genotype?
a)
AB, AB, aB, aB
b)
Ab, AB, Ab, ab
c)
Ab, Ab, Ab, Ab
d)
AB, aB, ab, aB
4.

A parent with genotype YyRR could produce which gametes?

a)

YR, YR, yR, yR

b)

Yy, Rr, yy, rr

c)

Yr, Yr, yr, yR

d)

YR, YR, yr, yr

5.

What genotype would go in box 1?

a)

AABb

b)

AABB

c)

aabb

d)

AaBb

6.

What genotype would go in box 3?

a)

AABb

b)

Aabb

c)

aabb

d)

AaBB

7.

If you cross two homozygous plants (RRYY x rryy)

R = round seeds, r = wrinkled seeds Y = yellow seeds, y = green seeds

What percent will have round and yellow seeds?

a)

0%

b)

25%

c)

50%

d)

100%

8.

A white mouse with red eyes is crossed with a black mouse with brown eyes. The white mouse is recessive for both of its traits. The black mouse is dominant for both of its traits.

This cross would be

a)

BBEE x bbee

b)

BBEe x BbEe

c)

BbEE x BbEe

d)

BBee x BBEE

9.
Assume mom's gametes are on the left, what is her genotype?
a)
TTZz
b)
TtZz
c)
ttZZ
d)
TtZZ
10.
The image above is an example of
a)
blending 
b)
a phenotype
c)
homozygous
d)
a dihybrid cross
11.
What genotype is missing from this Punnett Square?
a)
RrYy
b)
RRYY
c)
rryy
d)
RrYY
12.

How many alleles does a child get from each parent for a trait?

a)

1

b)

2

c)

3

d)

4

13.

Aa, DD, Bb, yy are all examples of ---

a)

genotypes.

b)

phenotypes.

14.

What you see, or the physical appearance of an organism, is called the ---

a)

genotype.

b)

phenotype.

15.

In a pedigree, which shape represents a male?

a)

circle

b)

square

16.

On a pedigree, this symbol represents a ----

a)

not affected male.

b)

not affected female.

c)

affected male.

d)

affected female.

17.

How are individuals III-2 and II-4 related?

a)

Brother and sister

b)

Dad and daughter

c)

Uncle and niece

d)

Grandfather and granddaughter

18.

What is the mode of inheritance shown here?

a)

Recessive because it "skips" a generation

b)

Dominant because it shows up in every generation

19.
Is this trait (the shaded individuals) dominant or recessive?
a)
dominant
b)
recessive
20.

If this pedigree shows a recessive disorder, what MUST the genotype of individual 4 be?

a)

HH

b)

Hh

c)

hh

21.
What do we use pedigrees for?
a)
To look at families
b)
To make determinations about the offspring
c)
To track traits in families
d)
Nothing
22.
What does a filled in square represent?
a)
Not affected Female
b)
Not affected Male
c)
Affected Male
d)
Affected Female
23.
What does a horizontal line between a square and a circle mean?
a)
They are siblings
b)
They are cousins
c)
They are married ("together")
d)
They are the children
24.
What does a vertical line coming down from a square and circle that are connected by horizontal line indicate?
a)
They are cousins
b)
The children
c)
Aunts and Uncles
25.
AA and Aa always show up as
a)
dominant
b)
recessive
26.
This pedigree represents the inheritance of hemophilia in this family. How many of the females have the hemophilia trait?
a)
8
b)
5
c)
2
d)
3
27.

How many alleles does a person carry for a trait?

a)

1

b)

2

c)

3

d)

4

28.

On this pedigree, the allele for curly hair is dominant. The couple labeled 2 both have curly hair, but have a daughter who does not have curly hair. Therefore, we can tell from the chart that for the couple labeled 2 -

a)

the male is heterozygous and the female is heterozygous.

b)

the male is homozygous recessive and the female is homozygous dominant.