Name: 
 

Ch 11 Introduction to Genetics Section 3, 4 & 5 Test



Multiple Choice (Value 16)
Identify the choice that best completes the statement or answers the question.
 

 1. 

Gene maps are based on
a.
independent assortment.
b.
the frequencies of crossing-over between genes.
c.
the number of genes in a cell.
d.
genetic diversity.
 

 2. 

Gregor Mendel’s principles of genetics apply to
a.
animals only.
c.
pea plants only.
b.
all organisms.
d.
plants only.
 

 3. 

Why did Thomas Hunt Morgan use fruit flies in his studies?
a.
Fruit flies share certain characteristics with pea plants.
b.
Fruit flies have a long lifespan.
c.
Fruit flies take a long time to produce offspring.
d.
Fruit flies produce a large number of offspring.
 
 
nar002-1.jpg

Figure 11–3
 

 4. 

What is shown in Figure 11–3?
a.
independent assortment
c.
crossing-over
b.
replication
d.
anaphase I of meiosis
 

 5. 

Gametes are produced by the process of
a.
replication.
c.
meiosis.
b.
mitosis.
d.
crossing-over.
 

 6. 

The number of chromosomes in a gamete is represented by the symbol
a.
Z.
c.
N.
b.
Y.
d.
X.
 

 7. 

Gametes have
a.
twice the number of chromosomes found in body cells.
b.
one allele for each gene.
c.
two sets of chromosomes.
d.
homologous chromosomes.
 

 8. 

Crossing-over rarely occurs in mitosis, unlike meiosis. Which of the following is the likely reason?
a.
Chromatids are not involved in mitosis.
b.
A cell undergoing mitosis does not have homologous chromosomes.
c.
There is no prophase during mitosis.
d.
Tetrads rarely form during mitosis.
 

 9. 

How many different allele combinations would be found in the gametes produced by a pea plant whose genotype was RrYY?
a.
16
c.
4
b.
8
d.
2
 
 
RrYy
  

RY

Ry

rY

ry
 
 

RY

RRYY

RRYy

RrYY

RrYy
Seed Shape
R =
Round
r =
Wrinkled


RrYy

Ry

RRYy

RRyy

RrYy

Rryy


Seed Color
Y =
Yellow
y = Green

rY

RrYY

RrYy

rrYY

rrYy
 

ry

RrYy

Rryy

rrYy

rryy
 

Figure 11–2
 

 10. 

The Punnett square in Figure 11–2 shows that the gene for pea shape and the gene for pea color
a.
are linked.
c.
have the same alleles.
b.
are always homozygous.
d.
assort independently.
 

 11. 

Which of the following assort independently?
a.
codominant alleles
c.
chromosomes
b.
multiple alleles
d.
genes on the same chromosome
 

 12. 

What principle states that during gamete formation genes for different traits separate without influencing each other’s inheritance?
a.
principle of probabilities
c.
principle of independent assortment
b.
principle of dominance
d.
principle of segregation
 

 13. 

Unlike mitosis, meiosis results in the formation of
a.
diploid cells.
c.
haploid cells.
b.
2N daughter cells.
d.
body cells.
 

 14. 

A cross of a black chicken (BB) with a white chicken (WW) produces all speckled offspring (BBWW). This type of inheritance is known as
a.
codominance.
c.
incomplete dominance.
b.
polygenic inheritance.
d.
multiple alleles.
 

 15. 

If an organism’s diploid number is 12, its haploid number is
a.
12.
c.
3.
b.
24.
d.
6.
 

 16. 

Chromosomes form tetrads during
a.
prophase I of meiosis.
c.
metaphase I of meiosis.
b.
anaphase II of meiosis.
d.
interphase.
 

Modified True/False (Value 7)
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
 

 17. 

If an organism is heterozygous for a particular gene, the two different alleles will be separated during anaphase II of meiosis, assuming that no crossing-over has occurred. _________________________

 

 18. 

Coat color in rabbits is determined by a single gene that has multiple alleles. _________________________

 

 19. 

Genes in the same linkage group are usually inherited separately. _________________________

 

 20. 

If an organism has four linkage groups, it has eight chromosomes. _________________________

 

 21. 

If two speckled chickens are mated, according to the principle of codominance, 25% of the offspring are expected to be speckled. _________________________

 

 22. 

Mitosis results in two cells, whereas meiosis results in one cell. _________________________

 

 23. 

If an organism has 16 chromosomes in each of its egg cells, the organism’s diploid number is 32. _________________________

 

Completion (Value 5)
Complete each statement.
 

 24. 

Crossing a pink-flowered four o’clock with a white-flowered four o’clock will produce pink-flowered offspring and ____________________-flowered offspring.
 

 

 25. 

The relative locations of each known gene can be shown on a ____________________ map.
 

 

 26. 

If pea plants that are homozygous for round, yellow seeds (RRYY) were crossed with pea plants that are heterozygous for round, yellow seeds (RrYy), the expected phenotype(s) of the offspring would be _________________________.
 

 

 27. 

An organism’s gametes have ____________________ the number of chromosomes found in the organism’s body cells.
 

 

 28. 

Crossing-over occurs during the stage of meiosis called ____________________.
 

 

Short Answer (Value 10)
 

 29. 

The gene map of a fruit fly’s chromosome 2 shows the relative locations of the star eye, dumpy wing, and black body genes to be 1.3, 13.0, and 48.5, respectively. Between which two genes does crossing-over occur most frequently?
 
 
RrYy
  

RY

Ry

rY

ry
 
 

RY

RRYY

RRYy

RrYY

RrYy
Seed Shape
R =
Round
r =
Wrinkled


RrYy

Ry

RRYy

RRyy

RrYy

Rryy


Seed Color
Y =
Yellow
y = Green

rY

RrYY

RrYy

rrYY

rrYy
 

ry

RrYy

Rryy

rrYy

rryy
 

Figure 11–2
 

 30. 

What is the phenotype ratio of the offspring in the Punnett square shown in Figure 11–2?
 

 31. 

What does a gene map show?
 

 32. 

What happens to the number of chromosomes per cell during meiosis?
 

 33. 

What is a linkage group?
 



 
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