2.0 Practice Test Questions
Source 08-09 EOI
Answer: B
Which of these is most likely to result from the processes of mutation and
crossing over during reproduction?
F offspring that are genetically identical to their parents
G offspring that are genetically identical to each other
H decreased genetic variation among offspring
J increased genetic variation among offspring
Answer: J
Source: 09-10 EOI
Answer: C
Answer: A
In pea plants, the allele for round seeds (R) is dominant to the allele for
wrinkled seeds (r). A gardener has two sets of parent plants, Set 1 and Set 2.
The parents in Set 1 are heterozygous for this trait. In Set 2, one parent is homozygous dominant and
the other is homozygous recessive.
The gardener wants to produce only round seeds. Which statement describes a correct prediction to
identify the parents he should use?
F Set 1 because one out of four offspring will inherit two alleles for round seeds.
G Set 2 because none of the offspring will be homozygous for wrinkled seeds.
H Set 1 because each seed will have a 25% chance of being wrinkled.
J Set 2 because all of the offspring will be homozygous for round seeds.
Answer: G
Purebred sweet peas with red flowers are crossed with purebred sweet peas with white flowers; all of
the offspring have pink flowers.
Predict the phenotypic ratio of the offspring if two sweet peas with pink flowers are crossed.
A 1:2:1
B 1:1:1
C 3:1
D 1:1
Answer: A
Source: 10-11 EOI
In a certain type of mouse, black fur is dominant and white fur is recessive. A scientist crosses a
heterozygous black mouse with a white mouse. What percentage of the offspring will most likely have
black fur?
F 0%
G 50%
H 75%
J 100%
Answer: G
Which of the following would be produced if a messenger RNA strand is coded from the DNA sequence
CCCGGAATT?
F CCCGGAAUU
G GGGCCTTAA
H AAATTCCGG
J GGGCCUUAA
Answer: J
Source: 10-11 EOI
The tips of chromosomes are composed of structures called telomeres. Telomeres shorten each time a
cell divides. When the telomeres are shortened to a set length, further cell division stops in most types
of cells. Scientists inserted a gene that produces the enzyme telomerase into normal skin and retinal
eye cells. This enzyme stops the shortening of telomeres during cell division. They found that these cells
continued to divide for 20 generations longer than skin and retinal eye cells without the inserted gene.
The scientists hope to use their research to develop treatments for disorders such as skin diseases and
retinal deterioration. What question should they answer first before using such treatments?
F Does inserting a telomerase gene in a skin cell allow it to divide more times?
G Do telomeres normally get shorter in retinal eye cells each time they divide?
H Does inserting a telomerase gene in a retinal eye cell increase the risk of a cell mutation?
J Do telomeres that are shortened through cell division to a set length stop further cell division?
Answer: H
Pipefish and sea horses, members of the Syngnathidae family, reproduce similarly. The female’s eggs are
placed into a pouch located on the male’s abdomen and remain there until they hatch. The presence of
this abdominal pouch can be used to construct which of these?
F a pedigree showing genetic inheritance
G a table listing genotypes of offspring
H a key using structural characteristics to identify organisms
J a pyramid showing energy flow in an ecosystem
Answer: H
Source: Californai Standards Test
Answer: A
If a corn plant has a genotype of Ttyy, what are the possible genetic combinations that could be present
in a single grain of pollen from this plant?
A Ty, ty
B TY, ty
C TY, Ty, ty
D Ty, ty, tY, TY
Answer: a
Answer; D
Answer: C
In fruit flies, the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is recessive. What are
the possible combinations of genes in the offspring of two red-eyed heterozygous flies (Rr)?
A RR only
B rr only
C Rr and rr only
D RR, Rr, and rr only
Answer: D
In certain breeds of dogs, deafness is due to a recessive allele (d) of a particular gene, and normal
hearing is due to its dominant allele (D). What percentage of the offspring of a normal heterozygous
(Dd) dog and a deaf dog (dd) would be expected to have normal hearing?
A 0%
B 25%
C 50%
D 100%
Answer: C
Answerr: D
If a human baby boy inherits a recessive allele from his mother, in which circumstance would he most
likely show the trait coded for by the recessive allele?
A The baby inherits the dominant allele from his father.
B The allele is on an autosomal chromosome and the baby is a twin.
C The allele is on the X chromosome.
D The allele is on the Y chromosome.
Answer: C
Answer: D
A base sequence is shown below.
ACAGTGC
How would the base sequence be coded on mRNA?
A TGTCACG
B GUGACAU
C UGUCACG
D CACUGUA
Answer: C
In carrier pigeons there is a rare inherited condition that causes the death of the chicks before hatching.
In order for this disease to be passed from generation to generation there must be parent birds that
A are heterozygous for the disease.
B have the disease themselves.
C produce new mutations for this disease.
D are closely interbred.
Answer: A
A healthy individual is a carrier of a lethal allele but is unaffected by it. What is the probable genotype of
this individual?
A
two dominant normal alleles
B
one recessive lethal allele and one dominant lethal allele
C
one recessive lethal allele and one dominant normal allele
D
one dominant lethal allele and one recessive normal allele
Anser: C