Chapter 5, Problem 12AQP

a.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual, which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. The genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Penetrance refers to as the percentage of individuals with a particular genotype that express the expected phenotype. Hence, the definition is correctly matched with term penetrance.

Explanation of Solution

Penetrance can be defined as the ability of the gene to express itself in an individual. The percentage of the population expressing the gene is mentioned as the percentage penetrance of the gene.

Thus, penetrance refers to the percentage of individuals with a particular genotype that express the expected phenotype.

b.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Sex-influenced trait is a trait determined by an autosomal gene that is more easily expressed in one sex. Hence, the definition is correctly matched with term sex-influenced traits.

Explanation of Solution

Sex-influenced traits are the traits that are expressed by the autosomal genes in a specific sex. For example – in goats, the $B^b$ gene in the male that express itself for the appearance of a beard on the face, but it is unable to express itself in female goat.

c.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Sex-limited trait is a trait determined by an autosomal gene that is more easily expressed in one sex. hence the definition is correctly matched with term sex-limited traits.

Explanation of Solution

Sex-limited traits are those traits that are limited to only one sex. These traits are expressed by autosomal genes or sex-limited genes. For example – The breast development is a characteristic trait which is generally limited to females, where the trait like beard growth is limited to males.

d.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Phenocopy is a phenomenon in which a trait is determined by an environmental effect and has the same phenotype as a genetically determined trait. Hence, the definition is correctly matched with term phenocopy.

Explanation of Solution

Phenocopy refers to as an individual that express a characteristic trait by a particular gene, and these genes can be copied in the other members of the species environmentally rather than genetically. For example – a butterfly (genus Vanessa) can alter phenotypic traits based on the temperature.

e.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Polygenic trait is a trait determined by genes at many loci. Hence the definition is correctly matched with term polygenic traits.

Explanation of Solution

Polygenic traits refers to the traits that are controlled by multiple genes present on different loci on the different or the same chromosomes of an individual. For example – human height and eye color are the polygenic traits determined by multiple genes.

f.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Genome imprinting is the phenomenon in which gene expression in an offspring is dependent on the sex of the mother or father which is transferred to the offspring. Hence the definition is correctly matched with term genome imprinting.

Explanation of Solution

The term genome imprinting can be defined as an inheritance process in which the gene expression completely depends on one of the parents. For example – The gene for the insulin-like growth factor II is expressed in the progeny, when the gene in the progeny  is inherited from the father.

g.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Anticipation is the phenomenon in which a gene that expresses itself earlier and is more severe in succeeding generations. Hence the definition is correctly matched with term anticipation.

Explanation of Solution

Anticipation refers to the phenomenon in which a gene that expresses itself into a particular trait, at an earlier age. These traits are passed from one generation to the next generation. For example - The inheritance of genetic disorder from one generation to next generations.

h.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

Pleiotrophy is the process in which a gene affects more than one phenotype. Hence the definition is correctly matched with term pleiotrophy.

Explanation of Solution

The term pleiotrophy is defined as the process in which a single gene is controlled multiple traits or phenotypes. For example- the gene determines the yellow coat color in mice is also responsible for the pre-natal death in the homozygous progeny.

i.

Summary Introduction

To match:

The following term with its correct definition.

Introduction:

Phenocopy refers to an individual which express characteristic features of genotype other than its own and produced environmentally rather than genetically. Pleiotrophy is the condition when a mutation causes two or more apparently observable effects. Polygenetic trait are the traits that are governed by two or more genes. Penetrance is the expressivity of a genotype in the phenotypes of the individual. Sex-limited traits are the traits that are expressed in one sex of a species, which are controlled by the sex-limited genes. Genetic maternal effect can be described as variation in the genotype or phenotype of maternal associated with the variation in the offspring phenotype is called maternal effect. Genome imprinting refers to the phenomenon that causes genes to be expressed in father (or mother) in an origin specific manner. Sex-influenced traits are the traits that are influenced by sex. Anticipation is a term that defines the inheritance of a genetic disorder from one generation to next, and symptoms appears at an earlier age.

Answer to Problem 12AQP

The term genetic maternal effect refers to the genotypes of the maternal parent that influences the phenotype of the offspring. Hence the definition is correctly matched with term genetic maternal effect.

Explanation of Solution

The condition when the phenotype of a progeny is governed by the genotype of the maternal nut not the genotype of the progeny, such phenomenon is coined as genetic maternal effect. For example –In snails, the coiling of the shell is determined by the genotype of the mother.