Ch.19 Genetics and Inheritance

If two individuals homozygous dominant for this trait have a child, what is the chance that the child will not be able to roll his tongue? A) 0% B) 25% C) 50% D) 75% E) 100%

A) 0%

A recessive allele associated with chromosome 15 causes an enzyme deficiency disease called A) Tay-Sachs. B) PKU. C) Patau syndrome. D) Turner syndrome. E) Edwards syndrome.

A) Tay-Sachs.

Which one of the following syndromes results in an individual with a nearly normal female phenotype and a tendency to develop mild mental retardation? A) Trisomy-X syndrome B) Klinefelter syndrome C) Double-Y syndrome D) Turner syndrome E) Trisomy-Y syndrome

A) Trisomy-X syndrome

Variations of homologous genes that result in differences in structure and function are A) alleles. B) loci. C) autosomes. D) dominant. E) linked.

A) alleles.

Cystic fibrosis is themost common fatal genetic disease in North America and results in what type of allele located on chromosome 7? A) recessive B) dominant C) homozygous D) heterozygous E) polygenic

A) recessive

Which of the following is characteristic of Klinefelter syndrome? A) sterility and mild mental impairment B) female phenotype C) XYY genotype D) nondisjunction of chromosomes after fertilization E) trisomy 18 genotype

A) sterility and mild mental impairment

If two individuals heterozygous for this trait have a child, what is the chance that the child will not be able to roll his tongue? A) 0% B) 25% C) 50% D) 75% E) 100%

B) 25%

The flower color in this plant is inherited by incomplete dominance. If a red flower that is homozygous dominant is crossed with a white flower that is homozygous recessive, the color of the offspring flowers will be expected to be A) all red. B) all pink. C) all white. D) 50% white and 50% pink. E) 50% white and 50% red.

B) all pink.

What is the significance of crossing-over, independent assortment, and random fertilization? A) an increase in the number of gametes produced by an individual, thereby increasing the chance that fertilization will occur B) an increasein the genetic diversity of gametes and zygotes C) an increase in the number of daughter cells produced by mitosis, thus providing a mechanism for rapidly repairing injured tissues D) a decrease in the genetic complexity of living systems, making it more likely that a species will survive E) a decrease in the amount of time it takes to produce gametes

B) an increase in the genetic diversity of gametes and zygotes

An example of a genotype is A) attached earlobes. B) homozygous dominant. C) brown hair color. D) long fingers. E) blood type AB.

B) homozygous dominant.

Failure of sister chromatids to separate properly is called A) segregation. B) nondisjunction. C) crossing-over. D) hemophilia. E) translocation.

B) nondisjunction.

Place the following in order from smallest, simplest, least complex, to largest and most inclusive . A) chromosome, gene, genome, nucleotide B) nucleotide, gene, chromosome, genome C) genome, chromosome, gene, nucleotide D) gene, nucleotide, genome, chromosome E) nucleotide, gene, genome, chromosome

B) nucleotide, gene, chromosome, genome

A couple has a daughter who is color-blind. The mother is not color-blind, but the father is. What is the genotype of the mother for this trait? A) two dominant alleles B) one dominant allele, one recessive allele C) three dominant alleles D) one abnormal Y chromosome, one normal X chromosome E) two recessive alleles

B) one dominant allele, one recessive allele

The trend toward increased height and weight due to improved nutrition in certain human populations is an example of the effect of ________ on phenotypes. A) gene linkage B) the environment C) codominance D) polygenic inheritance E) genetic disorders

B) the environment

A phenotypic trait is considered sex-linked when A) a trait occurs only in males. B) the genes for the phenotype occur on X or Y chromosomes. C) the phenotype is expressed only after sexual intercourse. D) the phenotype occurs only in females. E) the phenotype is polygenic for both sexes.

B) the genes for the phenotype occur on X or Y chromosomes.

A person born with Edwards syndrome has a genotypic condition identified as A) trisomy 21 .B) trisomy 18. C) nondisjunction. D) XO E) XXY.

B) trisomy 18.

Cystic fibrosis is a genetic disorder that results from the inheritance of two recessive alleles. What is the chance that a child will inherit the disorder if one parent is heterozygous for this gene and one parent has cystic fibrosis? A) 0% B) 25% C) 50% D) 75% E) 100%

C) 50%

If an individual homozygous dominant for widow's peak has a child with an individual heterozygous for widow's peak, what is the chance that the child will have a homozygous dominant genotype? A) 0% B) 25% C) 50%D) 75% E) 100%

C) 50%

Red-green color blindness is an X-linked recessive disorder. Assume that a mother is a carrier and a father is color-blind. What is the chance that their son will inherit red-green color blindness? A) 0% B) 25% C) 50% D) 75% E) 100%

C) 50%

Which one of the following genetic disorders is caused by the inheritance of a dominant-lethal allele? A) Down syndrome B) hemophilia C) Huntington's disease D) muscular dystrophy E) Klinefelter syndrome

C) Huntington's disease

A father is blood type B and a mother is blood type A. They have a child with blood type O. What are the genotypes of the father and mother? A) The father must be BB and the mother must be AO. B) The father must be BO and the mother must be AA. C) The father must beBO and the mother must be AO. D) The father must be BB and the mother must be AA. E) This isn't possible.

C) The father must beBO and the mother must be AO.

Which one of the following is TRUE regarding an individual who has inherited one sickle-cell gene and one normal gene for hemoglobin? A) The individual will develop sickle-cell anemia. B) The individual will produce only abnormal hemoglobin. C) The individual is more likely to resist malaria than an individual with two normal genes for hemoglobin. D) The individual will most likely die before the age of 10 from complications associated with abnormal white blood cells. E) The individual has the homozygous recessive genotype for this trait.

C) The individual is more likely to resist malaria than an individual with two normal genes for hemoglobin.

Which of the following genotypes results in a female phenotype? A) XY B) XYY C) XO D) XXY E) YO

C) XO

f a plant is inherited by complete dominance where homozygous dominant is a red flower color and homozygous recessive is a white flower color, what must the parents' genotypes be if the offspring was 25% white and 75% red? A) all red B) one homozygous dominant, the other heterozygous C) both heterozygous D) one homozygous recessive, the other heterozygous E) both homozygous dominant

C) both heterozygous

Genes represent the set of instructions for the expression of one or more traits human beings and influence human behaviors by A) directly causing specific changes in mood or patterns of behavior. B) producing protein products that serve as switches for directly turning on or off certain behaviors. C) directing the synthesis of protein products that influence but do not directly cause most human behaviors. D) activating behavior pathways, like those leading to depression or happiness. E) functioning as specific behavior suppressors.

C) directing the synthesis of protein products that influence but do not directly cause most human behaviors.

The law of segregation states that A) when two identical alleles come together, complete dominance occurs in terms of phenotype. B) genes for different traits assort independently of each other during the formation of egg and sperm. C) genes separate from each other during gamete formation so that each sperm and egg receive only one allele from each pair. D) when different alleles for the same trait come together, one allele will be recessive to another. E) different alleles for the same gene occupy unique loci on sister chromatids.

C) genes separate from each other during gamete formation so that each sperm and egg receive only one allele from each pair.

n 2008 the U.S. Congress passed GINA, an act that prevents insurance companies from A) requiring genetic testing for potential policy holders with a family history of certain types of genetic disorders. B) raising the rates of insurance premiums or denying coverage to people who have a pre-diagnosed health condition. C) increasing insurance costs for healthy individuals based on the results of genetic testing. D) denying insurance coverage to any U.S. citizen. E) refusing to pay for genetic screening of a fetus of a couple considered high risk for certain types of genetic diseases.

C) increasing insurance costs for healthy individuals based on the results of genetic testing.

Polygenic traits display phenotypes that A) are most commonly reflective of the heterozygous condition. B) usually express the dominate condition in greater than 75% of the population .C) represent a continuous range within the population. D) often are lethal to second generation of children. E) are masked by a codominance condition.

C) represent a continuous range within the population.

Alterations in chromosome number can occur with any chromosome, but most alterations are not seen in human populations because A) the phenotype is homozygous recessive. B) the phenotype is expressed in a continuous range in a given population and thus does not stand out. C) they are lethal during fetal development. D) most are corrected during the first mitotic event in the fertilized egg. E) the genotype still represents a normal condition.

C) they are lethal during fetal development.

When a piece of chromosome breaks off and reattaches at another site on the same or another chromosome, this is called A) a deletion. B) nondisjunction. C) translocation. D) nontranslation. E) recombination.

C) translocation.

If both alleles of a particular gene are identical, the person is said to be A) an identical twin. B) phenotypic. C) heterozygous. D) homozygous. E) genotypic.

D) homozygous.

In polygenic inheritance, A) all individuals in the population are initially heterozygous for a particular trait. B) the environment has no influence in phenotype expression. C) the genotype makeup of individuals in a population is the only factor influencing phenotypes. D) multiple alleles and genes contribute to a phenotype. E) all traits are expressed as incomplete dominance.

D) multiple alleles and genes contribute to a phenotype

The Punnett square is a useful tool for A) determining the rate of segregation of alleles. B) calculating how many mutations occur during DNA replication. C) determining which genes or traits assort independently during gamete formation. D) predicting the ratios of possible genotypes of a particular combination of alleles. E) predicting the level of crossing over that will occur during meiosis.

D) predicting the ratios of possible genotypes of a particular combination of alleles.

A couple is planning to have a child. The female is a carrier for hemophilia; the male does not have hemophilia. What is the chance that a female child will never develop hemophilia? A) 0% B) 25% C) 33% D) 50% E) 100%

E) 100%

If an individual homozygous dominant for this trait has a child with an individual who cannot roll his tongue, what is the chance that the child will have a heterozygous genotype? A) 0% B) 25% C) 50% D) 75% E) 100%

E) 100%

f an individual homozygous dominant for widow's peak has a child with an individual heterozygous for widow's peak, what is the chance that the child will have a widow's peak? A) 0% B) 25% C) 50% D) 75% E) 100%

E) 100%

If a piece of chromosome breaks off during mitosis or meiosis and does not reattach, the event is called A) nondisjunction. B) translocation. C) dysplasia. D) nondysplasia. E) a deletion

E) a deletion

Which of the following human traits is an example of codominance? A) sickle-cell anemia B) variation in eye color C) human height D) AB blood type E) both sickle-cell anemia and AB blood type

E) both sickle-cell anemia and AB blood type

The offspring resulting from a cross between a nearly white horse (cc) and a chestnut-colored horse (CC) isof an intermediate color (between white and chestnut). Which one of the following patterns of inheritance best explains this? A) complete dominance B) codominance C) sex-linked D) polygenic inheritance E) incomplete dominance

E) incomplete dominance

Which of the following is most likely involved in the determination of intelligence? A) one gene B) multiple genes C) the environment D) one gene and the environment E) multiple genes and the environment

E) multiple genes and the environment