Bio1012 - Biology Chapter 9

Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's first born child will be female and that their second born will be a male? A. 25% B. 75% C. 50% D. 20% E. 100%

A. 25%

Which of the following statements regarding genotypes and phenotypes is false: A. An allele that is fully expressed is referred to as recessive B. The expressed physical traits of an organism are called it's phenotype C. Alleles are alternate forms of a gene D. An organism with two different alleles for a single trait is said to be heterozygous for that trait E. The genetic makeup of an organism constitutes it's genotype

A. An allele that is fully expressed is referred to as recessive

A person with AB blood illustrates the principle of A. Codominance B. Blending inheritance C. Pleiotrophy D. Incomplete dominance E. Polygenic inheritance

A. Codominance

The mechanism that breaks the linkage between linked genes is: A. Crossing over B. Pleiotropy C. independent assortment D. Incomplete dominance E. Codominance

A. Crossing over

According to this figure heterozygote's for this form of hypercholesterolemia suffer from the disease because they: A. Don't produce enough LDL receptors B. Produce an abnormally shaped LDL receptor C. Don't produce any HDL receptors D. Don't produce any LDL receptors E. produce too many LDL receptors

A. Don't produce enough LDL receptors

Any gene located on a sex chromosome: A. Is called a sex linked gene B. Is called a dominant allele C. Will exhibit codominance D. Will exhibit pleiotropy E. It's called a recessive gene

A. It's called a sex linked gene

The chromosome theory of inheritance states that: A. The behavior of chromosomes during meiosis and fertilization accounts for the patterns of inheritance B. Chromosomes that exhibit mutations are the source of genetic variation C. The behavior of chromosomes during mitosis accounts for inheritance patterns D.then inheritance pattern of humans is predetermined from chromosomes E. Humans have 46 chromosomes

A. The behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance

Which of the following statements regarding hypotheses about inheritance is false? A. The blending hypothesis suggests that all of the traits of the offspring come from either the mother or the father. B. The theory of pangenesis, somatic incorrectly suggests that reproductive cells receive particles from somatic cells. C. Contrary to the theory of pangenesis, somatic cells do not influence eggs or sperms. D. The blending hypothesis does not explain how traits that disappear in one generation can reappear in later generations. E. Aristotle suggested that inheritance is the potential to produce body features.

A. The blending hypothesis suggests that all of the traits of the offspring come from either the mother or the father

The alleles of a gene are found at_______ chromosomes: A. The same locus on homologous B. The same locus on heterologus C. The same locus on homologous mitochondrial D. Different loci on heterologus E. Different loci on homologous

A. The same locus on homologous

Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50% what is the probability that a couples firstborn child will be female and that the second born child will be male A.25% B.75% C.50% D.20% E.100%

A.25%

Using a six-sided die, what is the probability of rolling either a 5 or a 6? A. 1/12 B. 1/3 C. 1/36 D. 1/6 E. 2/3

B. 1/3

The phenotypic ratio resulting from a dihybrid cross showing independent assortment is expected to be: A. 3:1 B. 9:3:3:1 C.9:1:1:3 D.3:9:9:1 E.1:2:1

B. 9:3:3:1

Sickle cell disease is an example of A. Codominance and multiple alleles B.codominance and pleiotropy C.multiple alleles, pleiotropy, and blended inheritance D. Multiple alleles and pleiotropy E. codominance and blended inheritance

B. Codominance and pleiotropy

All the offspring of a cross between a black eyed Mendelelien and an orange eyed Mendelian have black eyes. This means that the allele for black eyes is ______ the allele for orange eyes. A. Better than B. Dominant to C. Recessive to D. More aggressive than E. Codominant to

B. Dominant to

Which of the following statements regarding sickle cell disease is false? A. Sickle cell disease is common in tropical Africa B. Persons who are heterozygous for sickle cell disease are also resistant to malaria C. About one in 10 African-Americans as a carrier of sickle cell disease D. All of the symptoms of sickle cell disease result from the actions of just one allele E. Sickle cell disease causes white blood cells to be sickle shaped

B. Persons who are heterozygous for sickle cell disease are also resistant to malaria

All the offspring of a cross between a black eyed Mendelian and an orange eyed Mendelian have black eyes. What is the expected phenotypic ratio of a cross between two orange eyed Mendeliens? A. 1 black eyed: 0 orange eyed B. 3 black: 1 orange C. 0 black: 1 orange D. 1 black: 3 orange E. 1 black:1 orange

C. 0 black eyed: 1 orange eyed

If A is dominant at a and B is dominat to b, what is the expected phenotypic ratio of the cross: AaBb x AaBb A. 16:0:0:0 B. 8:4:2:2 C. 9:3:3:1 D. 4:4:4:4 E. 1:1:1:1

C. 9:3:3:1

For most sexually reproducing organisms Mendel's laws: A.help us understand the global geographic patterns of genetic disease B.explain the reasons why certain genes are dominant C. Cannot strictly account for most patterns of inheritance D. Clarify the phenomenon of incomplete dominance E.indicate if a particular genotype will cause a certain phenotype

C. Cannot strictly account for most patterns of inheritance

Dr. Smith's parents have normal hearing. However,Dr. Smith has an inherited form of deafness. Deafness is a recessive trait that is associated with the abnormal allele d. The normal allele at this locus, associated with normal hearing is D. Dr. Smith's parents could have which of the following genotypes: A.DD and DD B.DD and dd C.Dd and Dd d.Dd and DD E.dd and dd

C. Dd and Dd

Imagine that we mate two black Labrador dogs with normal vision and find that three of the puppies are like the parents but one puppy is chocolate with normal vision and another is black with PRA, we can conclude that: A. The alleles for color and vision segregate independently during gamete formation B. One of the parents is homozygous for both traits C. The alleles for color and vision segregate independently during gamete formation D. The same alleles that control coat color can also cause PRA E. Both of the parents are homozygous for both traits

C. The alleles for color and vision segregate independently during gamete formation

Which of the following kinds of data could be used to map the relative position of three genes on a chromosome? A. The frequencies of mutations in the gene B. Their frequencies with which the genes are inherited from the mother and from the father C. The frequency with which the corresponding traits occur together an offspring D. The frequency with which the genes exhibit incomplete dominance over each other E. The frequencies with which the genes are heterozygous

C. The frequencies with which the corresponding traits occur together in offspring

Recessive X-linked traits are more likely to be expressed in a male fruit fly that a female fruit fly because: A. The male chromosome is more susceptible to mutations B. Mills are haploid C. The males phenotype results entirely from his single X-linked Gene D. The males chromosome is more fragile than the females chromosome E. The males SRY gene doubles the chances that the sex linked genes are expressed

C. The males phenotype results entirely from his single x linked gene

A monohybrid cross is: A. The second generation of a self-fertilized plant B. A breeding experiment in which the parental varieties have on one trait in common C. A triploid plant that results from breeding two very different plants D. A breeding experiment in which the parental varieties differ in only one character E. A breeding experiment in which the parental varieties have only one prominent trait

D. A breeding experiment in which the parental varieties differ in only one character

The individual features of all organisms are the result of: A. The environment B. Genetics C. Genetics and cytoplasmic derminates D. Genetics and the environment E. The environment and individual needs

D. Genetics and the environment

All the offspring of a cross between a red flowered plant and a white flowered plant have pink flowers this means that the allele for red flowers is... To the allele for white flowers A. Codominant B. recessive C. Pleiotrophic D. Incompletely dominant E. Dominant

D. Incompletely dominant

Amniocentesis and chorionic villus sampling allow for ___ and ___ of the fetus so that it can be tested for abnormalities A. Direct observation... Biochemical testing B.imaging... Biochemical testing C.imaging... Karyotyping D.karyotyping... Biochemical testing E.sexing... Imaging

D. Karyotyping... Biochemical testing

The vast majority of people afflicted with recessive disorders are born to parents who were: A. Both affected by the disease B.affected by the disease but had subclinical symptoms C.slightly affected by the disease, showing some but not all of the symptoms D. Not affected by the disease E.subjected to some environmental toxin that caused disease in their children

D. Not affected at all by the disease

A colorblind woman marries a man who is not colorblind. All their sons but none of their daughters are colorblind. Which of the following statements correctly explains these results? A. The gene for color vision is in completely dominant to the Gene for sex determination B. The gene for color vision is linked to the Y- chromosome C. The gene for color vision is codominant with the gene for sex determination D. The gene for color vision is linked with the X chromosome E. The gene for color vision is completely dominant to the Gene for sex determination

D. The gene for color vision is linked to the X chromosome

How many sex chromosomes are in human gamete? A. Three B. Five C. Four D. Two E.One

D. Two

Genes located close together on the same chromosomes are referred to as... Genes and generally... A. Homologous... Inherited together B. Associated... Sort independently during meiosis C. codependent... Do not sort independently during meiosis D. Linked... Sort independently during meiosis E. Linked... Do not sort independently during meiosis

E.

A testcross is: A. The mating between an individual of a unknown genotype and an individual homozygous dominant for the trait of interest B. The mating between two individuals of unknown genotypes C. The meeting between two individuals heterozygous for the trait of interest D. A mating between individual of unknown genotype and individual heterozygous for the trait of interest E. A mating between an individual of unknown genotype and individual homozygous recessive for the trait of interest

E. A mating between an individual of a unknown genotype and individual homozygous recessive for the trait of interest

Research since Mendel's time has established the law of segregation of genes during gamete formation: A. Applies to all asexually reproducing organisms B. Applies to all forms of life C. Applies only to unicellular organisms D. Applies to all sexually reproducing organisms

E. Applies to all sexually reproducing organisms

Mendel's law of independent assortment states that: A. Independent sorting of genes produces polyploidy plants under some circumstances B. Chromosomes sort independently of each other during mitosis and meiosis C. Genes are sorted concurrently during gamete formation D. Each pair of alleles segregates independently of the other pairs of alleles during gamete formation E. Genes sort independently of each other in animals but not in plants

E. Genes sort independently of each other in animals but not in plants

A carrier of a genetic disorder who does not show symptoms is most likely to be ___to transmit it to offspring A.homozygous for the trait and able B.homozygous for the trait and unable C.Heterozygous for the trait and unable D.heterozygous for the trait and unlikely E.heterozygous for the trait and unable

E. Heterozygous for the trait and unable

Which of the following is essentially the opposite of pleiotropy: A. Blending inheritance B. Codominance C.incomplete dominance D. Multiple alleles E. Polygenic inheritance

E. Polygenic inheritance

Female inheritance patterns cannot be analyzed by simply studying the X-chromosome because: A. The X chromosome is too fragile for long term analysis B. The X chromosome is too difficult to isolate from other chromosomes C.The X-chromosome is too susceptible to mutations D. The X chromosome is physically too large to analyze accurately E. The X chromosome is obtained from both father and mother

E. The X-chromosome is obtained from both father and mother

Varieties of plants in which self-fertilization produces offspring that are to the parents are referred to as: A. Independent crosses B. The F2 generation. C. Hybrids. D. Monohybrid crosses E. True-Breeding

E. True-breeding

A testcross is: A.A mating between an individual of unknown genotype and individual homozygous dominant for the trait of interest B.The mating between two individuals of unknown genotype C.mating between two individuals heterozygous for the trait of interest D.The mating between an individual of unknown genotype and an individual heterozygous for the trait of interest E.A mating between an individual of unknown genotype an individual homozygous recessive for the trait of interest

E.A mating between an individual of unknown genotype and individual homozygous recessive for the trait of interest

Which of the following statements best explains why dominant alleles that cause lethal disorders are less common than recessive alleles that cause lethal disorders? A.unlike lethal disorders caused by recessive alleles, lethal disorders caused by dominant alleles usually caused the death of the embryo B.many lethal recessive alleles cause enhanced disease resistance when they are present in the heterozygous state and carriers of these alleles have more children on average than other people C. The presence of a lethal dominant allele causes sterility D.lethal disorders caused by dominant alleles are usually more severe than lethal disorders caused by recessive alleles E.most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce

E.most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, where as individuals carrying a lethal recessive allele are more likely to be healthy and reproduce