Deck 48: Genetics and Heredity

Question 1

Each DNA molecule may be called a:

A)chromatin strand.
B)chromosome.
C)gene.
D)Both A and B are correct.

Answer 1

D

Question 2

Mitochondrial DNA (mDNA):

A)is inherited as a result of both the sperm and the ovum.
B)has the potential for carrying mutations that produce disease.
C)is present only in lower forms of life.
D)Both A and B are correct.

Answer 2

B

Question 3

If "A" stands for the dominant gene that prevents albinism and "a" stands for the recessive albinism trait, then an individual with the genotype of "aa" will express:

A)albinism and will be a carrier.
B)albinism and will not be a carrier.
C)normal pigmentation and will be a carrier.
D)normal pigmentation and will not be a carrier.

Answer 3

A

Question 4

Which of the following is not a true statement?

A)The gametes contain only 23 chromosomes.
B)A zygote has a haploid number of chromosomes.
C)The pair of sex chromosomes may not match.
D)The 22 pairs of autosomes always appear to be nearly identical to each other.

Question 5

A DNA molecule is a:

A)gene.
B)chromosome.
C)genome.
D)gamete.

Question 6

A group of symptoms called Down syndrome results from trisomy:

A)15.
B)19.
C)21.
D)23.

Question 7

The sickle cell/malaria relationship demonstrates the concept in medical genetics that "disease" genes:

A)are always codominant.
B)are never dominant.
C)often provide some biological advantage for a human population in certain circumstances.
D)never provide a biological advantage for human populations.

Question 8

Assume that "A1" is the gene for light hair and that "A2" is the gene for dark hair. Also assume that these genes demonstrate codominance. Then, the heterozygous genotype "A1A2" will exhibit the phenotype of:

A)light hair.
B)dark hair.
C)hair color somewhere between light and dark.
D)red hair, because of the phenomenon of crossing over.

Question 9

An individual possessing the sex chromosome combination "XY" is genetically:

A)a male.
B)a female.
C)both.
D)neither.

Question 10

A female can inherit an X-linked recessive trait if her father:

A)is dominant and her mother is heterozygous for the trait.
B)is dominant and her mother is homozygous for the trait.
C)exhibits the trait and her mother is homozygous for the trait.
D)Both A and B are correct.

Question 11

Crossing over is the process during which:

A)similar gametes fuse together.
B)dissimilar gametes fuse together.
C)meiosis stops after meiosis I.
D)pairs of matching chromosomes line up along the equator of the cell and exchange genes with one another.

Question 12

Which of the following statements is not true of mitochondrial DNA?

A)The DNA is in the form of a circle.
B)The usual "stop" code in nuclear DNA codes for an amino acid in mitochondrial DNA.
C)The mitochondrial DNA in the zygote comes only from the mother.
D)All of the above statements are true of mitochondrial DNA.

Question 13

The condition called trisomy results from a(n):

A)mistake in mitosis called nondisjunction.
B)mistake in meiosis called nondisjunction.
C)abnormality in a single gene.
D)genetic predisposition.

Question 14

All of the following diseases demonstrate single-gene inheritance and are autosomal recessive except:

A)Tay-Sachs disease.
B)total albinism.
C)Huntington disease.
D)severe combined immune deficiency (SCID).

Question 15

Red-green color blindness shows X-linked recessive inheritance. Assume "X" is normal, "X1" is recessive for the trait, and "Y" is normal. Then, an individual with the genotype "XX1" will be a:

A)normal female and a carrier.
B)color-blind male.
C)normal female and not a carrier.
D)normal male.

Question 16

Cystic fibrosis, caused by recessive genes in chromosome pair 7, results in the impairment of the:

A)chloride ion transport across cell membranes.
B)sodium-potassium pump.
C)calcium-storing capacity of the body.
D)oxygen-carrying capacity of the blood.

Question 17

Gregor Mendel began the scientific study of genetics in the:

A)1760s.
B)1800s.
C)1860s.
D)1920s.

Question 18

The principle of independent assortment states that:

A)each offspring from a single set of parents is very likely to be genetically unique.
B)genetic variation is likely to occur during reproduction.
C)after meiosis, each gamete produced is likely to have a different set of 23 chromosomes.
D)all of the above are true.

Question 19

If an individual has only an X chromosome ("XO"), then that person is genetically:

A)male.
B)female.
C)neither male nor female.
D)The condition of "XO" can never occur.

Question 20

Which of the following statements is(are) true regarding Tay-Sachs disease?

A)Tay-Sachs disease results in the failure to make an essential lipid-processing enzyme.
B)This disease is most prevalent in Jewish populations.
C)This disease results in severe retardation and death by age 4.
D)All of the above are true regarding Tay-Sachs disease.

Question 21

An ordered arrangement of photographs of chromosomes from a single cell is called a:

A)genome.
B)karyotype.
C)Punnett square.
D)pedigree.

Question 22

About which percentage of the cell's DNA carry functional genes?

A)1%
B)10%
C)25%
D)50%

Question 23

In the therapy called gene augmentation:

A)genes that specify production of abnormal, disease-causing proteins are replaced by normal, or "therapeutic," genes.
B)hormones are used to treat the genetic disease.
C)diet is used to alleviate the symptoms of the genetic disease.
D)genetically altered cells are added to the body.

Question 24

When one or more DNA nucleotides are missing in a gene, it can be called a(n):

A)deletion.
B)insertion.
C)mutation.
D)Both A and C are correct.

Question 25

The parents with which of the following genotypes could not have a child with albinism?

A)AA x aa
B)Aa x Aa
C)Aa x aa
D)Both B and C

Question 26

The shorter segment of a chromosome is called the:

A)centromere.
B)s-arm.
C)p-arm.
D)q-arm.

Question 27

In human blood type, types A and B are codominant, producing type AB. They are both dominant to the recessive O type. Which of the following parental genotypes could produce a child with type O blood?

A)AB x AO
B)AO x BO
C)AO x BB
D)None of the above genotypes can produce a type O offspring.

Question 28

Carriers of cystic fibrosis are thought to be protected from:

A)malaria.
B)tuberculosis.
C)cholera.
D)the toxic effects of mold growing on grain.

Question 29

Which of the following processes does not aid in increasing the genetic variability of offspring?

A)Independent assortment
B)Gene linkage
C)Crossing over
D)All of the above aid in increasing the genetic variation of offspring.

Question 30

A karyotype would not be helpful in determining:

A)whether an individual has Down syndrome.
B)whether an individual has Turner syndrome.
C)whether an individual has PKU.
D)the sex of the offspring.

Question 31

Carriers of Tay-Sachs disease have a higher resistance to:

A)malaria.
B)tuberculosis.
C)cholera.
D)the toxic effects of mold growing on grain.

Question 32

"A" is the dominant allele for normal skin color; "a" is recessive for albinism. If a couple were "AA" and "Aa," which of the following statements is not true?

A)Both parents have the same phenotype.
B)Both parents have the same genotype.
C)They could not have a child with albinism.
D)All of the above are true statements.

Question 33

Which of the following is (are) not (a) mutagen(s)?

A)Radiation
B)Viruses
C)Chemicals
D)All of the above are mutagens.

Question 34

Assume that "A" is dominant for normal skin color and "a" is recessive for albinism. The parents with which of the following genotypes could have a child with albinism?

A)AA x AA
B)Aa x AA
C)AA x aa
D)Aa x Aa

Question 35

A chart that illustrates genetic relationships in a family over several generations is called a:

A)Punnett square.
B)pedigree.
C)genetic grid.
D)karyotype.

Question 36

Genes determine the structure and function of the body by regulating the body's production of:

A)carbohydrates.
B)lipids.
C)enzymes.
D)all of the above.

Question 37

The hypothesis regarding tumor suppressor genes states that these genes:

A)can transform a cell into a cancer cell only when certain environmental conditions occur.
B)regulate cell division so that it proceeds normally.
C)govern the cell's ability to repair damaged DNA.
D)Both A and C are correct.

Question 38

Which of the following conditions does not occur as a result of nondisjunction?

A)Tay-Sachs disease
B)Down syndrome
C)Turner syndrome
D)Klinefelter syndrome

Question 39

Phenylketonuria (PKU), caused by recessive genes in chromosome pair 12, is a condition characterized by:

A)impairment of chloride ion transport across all membranes.
B)failure to produce an enzyme needed to generate the amino acid tyrosine.
C)impairment of the blood's capacity to store oxygen.
D)impairment of the body's capacity to store calcium.

Question 40

The syndrome that results from the genotype "XXY" is:

A)Turner.
B)Klinefelter.
C)Down.
D)Parkinson.

Question 41

Diet soda containing NutraSweet should not be given to people with:

A)Tay-Sachs disease.
B)phenylketonuria.
C)osteogenesis imperfecta.
D)Diet soda would have no effect on any of the above conditions.

Question 42

In a pedigree, a half-shaded circle indicates a:

A)female that is a carrier for a trait.
B)male that is a carrier for a trait.
C)female with the trait.
D)male with the trait.

Question 43

If a pedigree tracing the albinism trait showed a square that was filled in, it would indicate a:

A)female had albinism.
B)male had albinism.
C)female had normal skin color.
D)male was a carrier for albinism.

Question 44

If a man had Leber hereditary optic neuropathy, a mitochondrial DNA-carried disease, what is the probability of him passing the trait on to his offspring?

A)100%
B)75%
C)0%
D)There is not enough information to determine the probability.

Question 45

The subunits of chromatin wound around a histone protein is called a:

A)gene.
B)chromosome.
C)nucleosome.
D)nucleotide.

Question 46

Chromosome 1 contains the most number of genes, nearly:

A)3000.
B)2000.
C)1000.
D)5000.

Question 47

Color blindness is a sex-linked trait. Which of the following parental genotypes could produce a color-blind female? (X' indicates the color-blind trait.)

A)X'X x XY
B)XX x X'Y
C)X'X x X'Y
D)X'X' x XY

Question 48

Coding portions of DNA tend to lie in clusters rich in which two nucleotides?

A)Thymine and cytosine
B)Cytosine and guanine
C)Cytosine and adenine
D)Thymine and adenine

Question 49

The products of meiosis are:

A)gametes.
B)haploid cells.
C)made only of autosomes.
D)both A and B.

Question 50

Which is a simple cartoon of a chromosome used to show the overall physical structure of a chromosome?

A)Genome
B)Transcriptome
C)Ideogram
D)Karyotype

Question 51

The chromosome that has the fewest genes contains only 200 genes and is called:

A)chromosome 1.
B)chromosome 7.
C)Y chromosome.
D)X chromosome.

Question 52

The human genome contains about _____ genes.

A)200,000 to 300,000
B)150,000 to 250,000
C)75,000 to 100,000
D)20,000 to 25,000

Question 53

In human blood type, A and B are codominant, producing type AB. They are both dominant to the recessive O type. If parents had genotypes AO and BO, a child with which blood type could be theirs?

A)A child with type A blood
B)A child with type B blood
C)A child with type O blood
D)All of the above children could be theirs.

Question 54

The entire collection of genetic material in each typical cell of the human body is called:

A)diploid.
B)haploid.
C)nucleosomes.
D)genome.

Question 55

Which of the following diseases is not a single-gene recessive trait?

A)Huntington disease
B)Tay-Sachs disease
C)PKU
D)All of the above are single-gene recessive traits.

Question 56

Which of the following diseases is not a single-gene dominant trait?

A)Huntington disease
B)Cystic fibrosis
C)Osteogenesis imperfecta
D)All of the above are single-gene dominant traits.

Question 57

If a karyotype found an X chromosome, a Y chromosome, and three 21st chromosomes, it would indicate a _____ syndrome.

A)female with Down
B)female with Turner
C)male with Klinefelter
D)male with Down

Question 58

Which of the following is not a type of RNA?

A)Mitochondrial RNA
B)Ribosomal RNA
C)Transfer RNA
D)All of the above are types of RNA.

Question 59

The genetic code is transmitted to offspring in discrete, independent units that are called:

A)chromosomes.
B)genes.
C)gametes.
D)nucleosomes.

Question 60

Which of the following diseases is carried by mitochondrial DNA?

A)Retinitis pigmentosa
B)Severe combined immune deficiency
C)Ocular albinism
D)None of the above diseases is carried by mitochondrial DNA.

Question 61

Gregor Mendel proved that "independent units" are responsible for the inheritance of biological traits.

Question 62

The X chromosome and the Y chromosome are the same size.

Question 63

Sickle cell inheritance is a good example of how codominance works.

Question 64

In the human, the 22 pairs of autosomes always appear to be nearly identical to each other.

Question 65

A person who is heterozygous for albinism will have the abnormal phenotype for the condition.

Question 66

Theoretically, the best chance for producing a girl infant would be for insemination to occur on the day of ovulation.

Question 67

The principle of independent assortment states that each gamete formed is likely to have the same set of 23 chromosomes.

Question 68

A sperm containing a Y chromosome swims faster than a sperm containing an X chromosome.

Question 69

The Y chromosome is larger than the X chromosome.

Question 70

The X chromosome contains few genes other than those that determine female sexual characteristics.

Question 71

Exons are removed from transcribed RNA to form the functional mRNA strand.

Question 72

Every cell in the human body, both male and female, contains 46 chromosomes.

Question 73

The manner in which the genotype is expressed is called the phenotype.

Question 74

Crossing over is a unique phenomenon that prevents genetic variation among offspring of a single set of parents.

Question 75

Genetic mutations are always harmful.

Question 76

Both males and females have an X chromosome.

Question 77

Disease genes never provide biological advantages for human populations, regardless of the circumstances.

Question 78

Gene linkage decreases the likelihood of genetic variation among the offspring of a single set of parents.

Question 79

DNA molecules are segments of a gene.

Question 80

Each offspring from a single set of parents is likely to be genetically unique.