CH 29

Pedigree analysis is most useful __________________.

for screening and genetic counseling before conception

A type of treatment useful in correcting single-gene disorders is __________.

gene therapy

Match the following type of inheritance with its correct phenotype: Polygene inheritance.

height

Match the type of inheritance with the correct phenotype: Sex-linked.

hemophilia

Match the mode of genetic expression with the correct characteristic: Incomplete dominance.

heterozygote has a phenotype that is intermediate between the homozygous dominant and recessive phenotypes

When the two alleles controlling a trait are different, the individual is __________ for the trait.

heterozygous

The form of inheritance in which the heterozygous state is expressed as an intermediate is __________.

incomplete dominance

What will the offspring's blood type be if the mother is type B, and father is type AB?

Type A, type B, or type AB

What will the offspring's blood type be if the mother is type O, and father is type O?

Type O

what is the function of a pedigree?

a diagram that traces the inheritance of a particular trait through generations

A cell from a person with trisomy 21 (Down Syndrome) contains __________.

a nondisjunction

Which of the following can be used to deliver a functional copy of an affected gene into cells?

a virus

Match the genetic term with its correct characteristic: Genotype.

actual genetic makeup

Alternative forms of genes are called __________.

alleles

A person without a Y chromosome will __________.

always show female characteristics

Match the genetic term with its correct characteristic: Allele.

an alternate gene form

A phenocopy occurs when __________.

an individual develops a phenotype that is similar to a condition caused by mutant genes but is actually caused by environmental factors and does not have a genetic basis

Linked genes __________.

are on the same chromosome

Any two matched genes that are __________ are called alleles.

at the same locus on homologous chromosomes

For most genes, both the maternal and paternal alleles are expressed __________.

at the same time

If the allele for brown hair is represented as "B," it would mean that __________.

brown hair is a dominant trait

Heterozygous individuals that can pass on recessive, abnormal conditions even if they do not express the disease are referred to as __________.

carriers

In females, one of the X chromosomes is inactivated by __________.

epigenetic marks

Epigenetics primarily shows all of the following except __________.

epigenetics accounts for inactivation of the Y chromosome in males

Amniocentesis and chorionic villus sampling are both examples of a category of genetic screening called __________.

fetal testing

Which of the following processes may separate linked genes during meiosis?

Chiasma, or crossover

Traits that display continuous phenotypic variation are usually determined by this form of inheritance.

polygene inheritance

What pattern of inheritance results from the effects of multiple genes at different chromosome locations to produce one overall phenotype?

polygene inheritance

Which of the following does not match the term to its correct definition/description?

recessive: gene expressed when present

Red-green color blindness exhibits __________ inheritance.

sex linked

Which type of inheritance involves genes not located on autosomal chromosomes?

sex-linked inheritance

Males tend to inherit more sex-linked conditions because __________.

there is no corresponding allele on their Y chromosomes.

The technique known as CRISPR-Cas9 is a ___________________.

way to make changes directly to genes

Which of the following statements is true?

Environmental factors can influence gene expression after birth.

Which of the following statements regarding gene expression is true?

Environmental factors can override or influence gene expression.

A karyotype is a complete __________.

display of homologous chromosome pairs

An allele that is able to mask the expression of its partner allele is said to be __________.

dominant

What type of allele will be expressed if both dominant and recessive alleles are present for a given trait?

dominant

Most human traits are determined by __________.

multiple alleles

A permanent change in the genetic structure of a gene is called __________.

mutation

Which of the following is not one of the three basic levels of gene control?

mutations

Match the mode of genetic expression with its correct characteristic: Dominant-recessive inheritance.

one allele can mask the other allele

Which of the following is a noninvasive method for predicting genetic disease?

pedigree

The expression of genes is called the __________.

phenotype

The most common form of fetal testing is __________.

Amniocentesis

What is the chance the offspring will possess these traits or diseases: albinism, if both parents are heterozygous for the albino gene?

25%

What is the probability of having a child with a recessive trait if both parents are heterozygous for the trait?

25%

In a dominant disorder like Huntington's, if the mother is homozygous recessive and the father is homozygous recessive, what is the likely percentage of offspring that will be affected?

0% affected

In a recessive disorder like Cystic Fibrosis, if the mother is homozygous dominant and the father is homozygous recessive, what is the likely percentage of offspring that will be affected?

0% affected

In a recessive disorder like cystic fibrosis, if the mother is homozygous dominant and the father is heterozygous, what is the likely percentage of offspring that will be affected?

0% affected

In a recessive disorder like cystic fibrosis, if the mother is homozygous dominant and the father is homozygous dominant, what is the likely percentage of offspring that will be affected?

0% affected

What is the probability of the same couple having three girls in a row?

1/8

In a dominant disorder like Huntington's, if the mother is homozygous dominant and the father is heterozygous, what is the likely percentage of offspring that will be affected.

100% affected

In a dominant disorder like Huntington's, if the mother is homozygous dominant and the father is homozygous dominant, what is the likely percentage of offspring that will be affected.

100% affected

In a dominant disorder like Huntington's, if the mother is homozygous recessive and the father is homozygous dominant, what is the likely percentage of offspring that will be affected?

100% affected

In a recessive disorder like Cystic Fibrosis, if the mother is homozygous recessive and the father is homozygous recessive, what is the likely percentage of offspring that will be affected?

100% affected

How many chromosome pairs are in a normal diploid human cell?

23

Humans have __________ pairs of chromosomes.

23

In a recessive disorder like cystic fibrosis, if the mother is heterozygous and the father is heterozygous, what is the likely percentage of offspring that will be affected?

25%

In a sex-linked disorder like hemophilia, if the mother is heterozygous and the father is affected, what is the likely percentage of offspring that will be affected?

25% affected female, 25% normal female carrier, 25% normal male, 25% affected male

In a sex-linked disorder like hemophilia, if the mother is heterozygous and the father is normal, what is the likely percentage of offspring that will be affected?

25% normal non-carrier female, 25% normal female carrier, 25% normal male, 25% affected male

The number of different gametes that can be produced in a male, based on independent assortment alone, equals __________.

2^23

Use the following information to solve the problem using a Punnett square: Assume that the dominant "A" allele encodes normal pigmentation and the recessive "a" allele encodes albinism. An individual with the genotype aa has children with an individual of the genotype Aa. What is the percent chance that they would have children with albinism?

50%

In a dominant disorder like Huntington's, if the mother is homozygous recessive and the father is heterozygous, what is the likely percentage of offspring that will be affected?

50% affected

In a recessive disorder like Cystic Fibrosis, if the mother is homozygous recessive and the father is heterozygous, what is the likely percentage of offspring that will be affected?

50% affected and 50% carriers

In a sex-linked disorder like hemophilia, if the mother is homozygous dominant and the father is affected, what is the likely percentage of offspring that will be affected?

50% normal female carrier, 50% normal males

In a dominant disorder like Huntington's, if the mother is heterozygous and the father is heterozygous, what is the likely percentage of offspring that will be affected?

75% affected

Match the mode of genetic expression with the correct characteristic: Sex-linked inheritance.

A gene is found only on the X chromosome

Sam has type A blood. The blood type of his partner is not known. Which of the following blood types are not at all possible among their offspring?

All of the listed blood types are possible.

Which statement is false?

An autosome refers to genes carried on the Y chromosome.

A person who inherits the B and the O blood type alleles will possess which blood type?

B

A method that is likely to make invasive fetal testing methods obsolete is ______________.

DNA sequencing

Which of the following statements regarding dominant and recessive alleles is false?

Dominant and recessive refer to the frequency of an allele in the population.

Which statement is false?

Genes essentially act as free agents.

Which of the following statements is true?

It takes relatively few genes to build a human being.

Which statement is false with regard to alleles J and j?

JJ would indicate a homozygous recessive condition.

Which of the following statements about genomic imprinting is false?

Once genomic imprinting occurs, it never changes.

Match the genetic term with its correct characteristic: Phenotype.

The way the genotype is expressed (for example, skin color)

Which of the following statements regarding small RNAs is false?

They make up about 20% of our genome.

In the human blood type AB, the alleles are __________.

codominant

Freckles are a completely dominant trait. Both of Jason's parents have freckles. Jason does not have freckles. What type of inheritance describes this situation?

complete dominance, In this scenario, it would seem that Jason's parents are both heterozygous for a completely dominant trait. They have each donated a recessive allele to Jason, which is why they express a trait that he does not.

If a male inherits a sex-linked gene for color blindness __________.

it will always be expressed

Genes that are located on the same chromosome are said to be __________.

linked genes

A sperm cell is produced by __________.

meiosis

Extranuclear inheritance involves genes passed on by the mother's __________.

mitochondria

Nuclear DNA is not the only source of genetic information in the cell. Which of the following is another source of DNA in the cell?

mitochondria, Mitochondria have their own DNA separate from the nuclear DNA of the cell.

Genetic variation is not enhanced through __________.

mitosis

Which of the following is not a source of genetic variation?

mitosis of fertilized egg

The 46 chromosomes of a zygote come from __________.

mother and father

Match the genetic term with its correct characteristic: Genome.

the set of all genes