Generic Biology: Multiple Choice Questions

CHAPTER 29 Multiple Choice ALPHEBETIZED
________ is the most common type of fetal testing.
Amniocentesis
A chromosomal aberration in which part of a chromosome is lost is known as ________. deletion A female infant is born with several hundred oocytes, each one genetically unique. This is due to ________. independent assortment and random crossover
An allele that can be masked or suppressed by another allele is said to be __________.Recessive
A couple whose blood types are A (IAi) and B (IBi) may have a child with which of the following blood types?
A, B, AB, or O
Amy's hand was exposed to X rays. A gene in a skin cell of her hand mutated. This mutant gene will ________. replicate itself when the cell divides but will not be passed on to Amy's offspring
An example of multiple-allele inheritance is ________. the ABO blood group
An individual who is heterozygous for a particular trait, yet expresses both alleles of that trait, is an example of ________.incomplete dominance
An organism with three pairs of homologous chromosomes statistically could produce __________ different gametes strictly on the basis of independent assortment. 8
A woman has blond hair and brown eyes. This statement is best described as indicating ________.phenotypeBoth of Jason's parents are homozygous dominant for tall. Jason has inherited the homozygous dominant trait for tallness. Jason, however, is quite short. Which of the following could explain why Jason is short? effect of the environment on gene expression
Dominant alleles are so called because under most circumstances they ________. suppress the expression of other alleles
For which of the following are newborn infants not routinely screened at birth? color blindness
Gene mutations in the sex chromosomes of the human would tend to become visibly expressed ________. more frequently in males
Genes on the same chromosome are said to be __________.Linked
How many chromosomes are in a diploid human cell?46
Huntington's disease involves ________.degeneration of the basal nuclei of the brain
In meiosis the spermatozoa that are produced are genetically unlike each other and unlike the cell that produces them. This is one reason for the great variation among humans. What causes this effect? crossing-over and independent assortment only
Inheritance of stature (height) in humans is probably due to ________.polygene inheritance
Is genetic diversity due entirely to inherited genes on the sex chromosomes?
No, because genetic diversity has nothing to do with the sex chromosomes but is due to crossing-over of chromosomes, independent assortment of chromosomes, and segregation of chromosomes.
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? mitochondriaPedigrees and blood tests are both means of __________. carrier recognition
Recessive genes are usually expressed in humans only when ________. both alleles are exactly the same, or homozygous
Sam has type A blood. What type of inheritance produced that blood type? multiple-allele inheritance
Sex chromosomes of a normal male are ________.XY
Skin color, controlled by three separately inherited genes that each exist in two allelic forms (A, a; B, b; C, c), is an example of which form of inheritance? polygene inheritance
The gene responsible for the condition known as sickle-cell anemia demonstrates ________. incomplete dominance
The genetic determination of blood type is based on __________ inheritance. multiple-allele The main way a recessive allele would be expressed even when only one copy is present would be ________. sex-linked inheritance
The reason recessive genetic disorders are more frequent than disorders inherited as dominant is that ________. carriers are not eliminated by the disease before passing the defective alleles on to their offspring
Those characteristics that can be determined on superficial inspection of an individual are known as ________.
Phenotypic
Two alleles expressing exactly the same information for a trait are designated as ________. homozygousUse the following information to solve the problem using a Punnett square. Assume that the dominant "B" allele encodes brown eyes and the recessive "b" allele encodes blue eyes. An individual with the genotype BB has children by mating with an individual of the genotype bb. What is the percent chance that they would have children with blue eyes?
0%
What is the probability of the same couple having three boys in a row?1/8
What type of inheritance is responsible for the great diversity of skin color, height, metabolic rate?polygenic inheritance
When alleles controlling a trait are the same, they are said to be __________.
Homozygous
Which of the following INCORRECTLY matches the term to its definition? recessive/gene expressed when present
Which of the following is an example of a disorder that exhibits incomplete dominance? sickle-cell anemia
Which of the following is a noninvasive method for predicting genetic disease? pedigreeWhich of the following is NOT a source of genetic variation? age of either or both parents
Which of the following is NOT a part of the genome control system? phenocopiesWhich of the following is true concerning environmental influence on genetic expression?
Drugs and nutrition can alter normal gene expression
Which of the following statements is true concerning genetic screening?
Screening can be done before conception by carrier recognition or during fetal testing.
Which of the following is true of the Punnett square?
It predicts only the probability of a particular genotype and phenotype
Which type of inheritance involves genes found on an X chromosome? sex-linked inheritance
TRUE FALSE
A person's genetic makeup is referred to as his or her phenotype.False
A Punnett square is a diagram that may be used to figure out the possible combinations of genes for a trait.True
Alleles may code for alternative expressions of a genetic trait. True
Because lethal dominant genes are always expressed and result in the death of the embryo, fetus, or child, dominant gene disorders are NOT seen among adults.False
Delayed action genes can result in fatal diseases.True
Down syndrome is an example of nondisjunction of chromosomes.True
Each human being (with the possible exception of identical siblings) has a unique genotype and phenotype. True
Environmentally produced phenotypes that mimic conditions that may be caused by genetic mutation are called phenocopies.True Genetic segregation implies that the members of the allele pair determining each trait are distributed to different gametes during mitosis.False
Genetic variation results from the crossing over and exchange of chromosomal parts that occur during meiosis II.
False
Hemophilia is an X-linked condition caused by a recessive gene.True
Hereditary characteristics are transmitted to offspring by genes. True
In incomplete dominance, the heterozygote has a phenotype intermediate between that of homozygous-dominant and homozygous-recessive individuals.True
It is possible for a baby to have type O blood if neither parent is type O.True
Mitochondrial genes are free of errors. As a result, all genetic problems are due exclusively to nuclear genes.
False
Most genetic disorders are inherited through dominant genes. False
Normal vision is dictated by the autosomal dominant genes. False
Small RNAs control the timing of programmed cell death during development.True
Some segments of the Y chromosome have no counterpart on the X chromosome.True
The expression of all physical traits is strictly due to the inheritance of specific genes.False
The same allele can have a different effect depending on which parent it comes from.True
The term lethal dominant gene indicates that the gene causes death only when the individual is homozygous.
False
The X and Y sex chromosomes are NOT homologous.True
PICTURES

What is the name of the condition when a person has inherited the genotype HH? homozygous dominant
When one chromatid segment has formed a chiasma with a homologous chromatid segment, what is the result? recombinant chromosomes
What do chiasmas promote? genetic variability

In this figure, hair color genes and eye color genes are located on the same chromosome. Since these genes are transmitted as a unit to daughter cells during mitosis, we describe these genes as ____________. Linked
For a cell with a five homologous pairs, calculate how many different gamete types can result from meiosis. 32
During metaphase of meiosis I, the alleles determining each trait are distributed to different gametes. What is this called? segregation
How many chromatids are present in a tetrad? Four
During what phase of meiosis do the tetrads align together along the metaphase spindle? metaphase I
If a cell has a diploid number of 22, how many total chromosomes should it have? 22

Using the information provided in this figure, what is the probability of producing a homozygous dominant offspring?
25%
Using the information provided in this figure, what is the probability of producing an offspring who can roll their tongue?
%75
Using the information provided in this figure, what is the probability of producing an offspring who CANNOT roll his or her tongue? 25%
When two genes are on the same chromosome, they are considered linked.True
Which of the following is NOT the tongue-roller genotype? TtUsing the information provided in this figure, what is the genotype of a homozygous recessive offspring? ttUsing the information provided in this figure, what is the probability of producing an offspring whose phenotype is that of tongue-roller? 75%

Continuous phenotypic variation between two extremes results from _________. polygenic inheritance
Three genes control skin color. How many possible combinations of skin color result from those three genes? 64
Which of the following exemplifies polygenic inheritance? height
What type of fetal testing provides results within a day or so of the test? chorionic villus sampling
At how many weeks of pregnancy can chorionic villus sampling (CVS) be safely performed? 10
At what age are both amniocentesis and chorionic villus sampling routinely ordered when a woman is pregnant to test for Down syndrome? 35

Given the information in the figure, what would be the genotype of the offspring designated by the blank square? gg Given the information in the figure, what would the genotype ratio be for the offspring?
1:2:1
Given the information in the figure, what is the phenotype ratio (assuming C is dominant and there is no incomplete dominance)?
3:1
Given the information in the figure, if C were an incomplete dominant trait, what would the phenotype ratio be for the offspring?
1:2:1