Question 1

Genes that are located on the same chromosome

Accepted Answer

A)  tend to be inherited together. 
B)  will appear together in the gamete. 
C)  are said to be linked. 
D)  may be separated during chromosome pairing and crossing over. 
E)  fit all of these characteristics.

Question 2

Purple flower ( A ) is dominant over white flower ( a ), and tall stem ( B ) is dominant over short stem ( b ). The Punnett square represents a cross between two dihybrids ( AaBb ´ AaBb ). Examine the figure above, and answer the following question(s). In the figure above, how many plants would have the genotype AaBb ?

Accepted Answer

A)  1 
B)  3 
C)  5 
D)  6 
E)  9

Question 3

In a family pedigree of several generations, it is found that freckles appear in every generation and affect both sexes equally. Freckles is most likely a _____ trait.

Accepted Answer

A)  dominant 
B)  recessive 
C)  X-linked 
D)  epistatic 
E)  pleiotrophic

Question 4

If two individuals both heterozygous for the same genes (e.g., AaBb) mate and have offspring, how many different phenotypes will there be?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 5

The discarded theory of blending inheritance appears most like

Accepted Answer

A)  X-linked inheritance. 
B)  dihybridization. 
C)  codominance. 
D)  incomplete dominance. 
E)  complete dominance.

Question 6

When two alleles of the same gene are different, the individual carrying those alleles is said to be

Accepted Answer

A)  recessive. 
B)  heterozygous. 
C)  phenotypic. 
D)  somatic. 
E)  homozygous.

Question 7

If a normal egg is fertilized by a sperm which has an extra chromosome, what will be the chromosomal condition of the zygote?

Accepted Answer

A)  three copies of the affected chromosome and two of all others 
B)  three copies of all chromosomes 
C)  four copies of the affected chromosome and two of all others 
D)  one copy of the affected chromosome and two of all others 
E)  two copies of all of the chromosomes

Question 8

Blood types (A, B, and O) are controlled by

Accepted Answer

A)  sex-linked genes. 
B)  linked genes. 
C)  incompletely dominant genes. 
D)  multiple alleles. 
E)  simple dominance.

Question 9

In cats, short hair L is dominant to long hair l, and black hair B is dominant to brown hair b . If you found a black, short-haired cat, you could determine his genotype by crossing it to an animal with a genotype of

Accepted Answer

A)  LLBB . 
B)  llBB . 
C)  llBb . 
D)  llbb . 
E)  LLbb .

Question 10

Mendel's dihybrid crosses (but not his monohybrid crosses) showed that

Accepted Answer

A)  some genes were linked together. 
B)  the two alleles controlling a trait were divided equally among the gametes. 
C)  alleles for different traits were inherited independently. 
D)  one of the pair of alleles is dominant to the other. 
E)  the crossing of two different homozygous forms will not produce any offspring in the first generation that would look like either of the parents.

Question 11

What could the children of a color-blind woman and a man with normal vision be?

Accepted Answer

A)  All will be color-blind. 
B)  None will be color-blind. 
C)  Daughters will be color-blind, and sons will be normal. 
D)  Sons will be color-blind, and daughters will be normal. 
E)  About half would be color-blind.

Question 12

Which of the following would be considered a carrier of a sex-linked recessive defect?

Accepted Answer

A)  a man with the defect 
B)  a woman with the defect 
C)  a father of a son with the defect 
D)  the normal daughter whose father had the defect 
E)  a son of two unaffected parents

Question 13

Which of the following statements is FALSE?

Accepted Answer

A)  Crossing over tends to reduce the frequency that two linked genes are inherited together. 
B)  Independent assortment of homologous chromosomes during meiosis increases variation. 
C)  Crossing over leads to variation. 
D)  Abnormal number or structure of chromosomes may influence the course of evolution. 
E)  The closer together genes are found on a chromosome, the greater is a chance that crossing over will occur between them.

Question 14

Which of the following was Mendel's experimental organism?

Accepted Answer

A)  pea plants 
B)  mustard plants 
C)  tobacco plants 
D)  corn plants 
E)  bean plants

Question 15

The ABO blood types are examples of

Accepted Answer

A)  multiple alleles and codominance. 
B)  pleiotropy. 
C)  multiple alleles. 
D)  incomplete dominance. 
E)  codominance.

Question 16

Which of the first three statements about independent assortment is NOT true?

Accepted Answer

A)  genes on homologous chromosomes assort independently 
B)  genes on the same chromosome that are far apart tend to assort independently 
C)  genes close together on the same chromosome tend to assort independently 
D)  all of the first three statements about independent assortment are NOT true 
E)  one of the first three statements about independent assortment is NOT true

Question 17

Amniocentesis is

Accepted Answer

A)  a surgical means of repairing deformities. 
B)  a form of chemotherapy that modifies or inhibits gene expression or the function of gene product. 
C)  used in prenatal diagnosis to detect chromosomal mutations and genetic disorders in embryos. 
D)  a form of gene replacement therapy. 
E)  all of these.

Question 18

What two types of melanin are made by melanosomes?

Accepted Answer

A)  brownish- black and yellowish 
B)  brownish-black and reddish 
C)  brownish-black and white-ish 
D)  yellowish and reddish 
E)  reddish and white-ish

Question 19

Which of the following chromosomal conditions is treated with testosterone injections?

Accepted Answer

A)  XXX 
B)  trisomy 21 
C)  XO 
D)  XXY 
E)  XYY

Question 20

Selecting the Exception Four of the five answers listed below are related conditions in which abnormal numbers of chromosomes are present. Select the EXCEPTION.

Accepted Answer

A)  monosomy 
B)  aneuploidy 
C)  polyploidy 
D)  diploidy 
E)  trisomy

Exam 9: Patterns of Inheritance