Genetics 301

1. A genetic map allows geneticists to understand the overall complexity and genetic organization of a particular species. ( T or F)

1. True

The Manx phenotype in cats is caused by an autosomal dominant allele that is lethal in the homozygous state. Cats that are homozygous recessive have a normal tail. A female Manx cat mates with a male Manx cat. What percentage of the offspring is expected to have normal tails? A. 1/2 B. 2/3 C. 3/4 D. None, this is a lethal allele. E. 1/3

1/3

When Mendel crossed two plants that were heterozygous for a single trait, what was the genotypic ratio of their offspring?

1:2:1

2. Knowing the locus of a gene within a genetic map can help molecular geneticists clone the gene. ( T or F)

2. True

3. Genetic maps can be used to improve our understanding of the evolutionary relationships among species. ( T or F)

3. True

When Mendel crossed two plants that were heterozygous for a single trait, what was the phenotypic ratio of their offspring?

3:1

4. Genetic maps can be used to diagnose and perhaps someday treat inherited human diseases. ( T or F)

4. True

5. Genetic counselors can use genetic maps to determine if an individual will express a particular gene. ( T or F)

5. False

6. Genetic maps provide plant and animal breeders with helpful information for improving agriculturally important strains through selective breeding programs ( T or F)

6. True

Recall that in pea plants, purple flower color is dominant and white is recessive. If two heterozygous plants are crossed, what is the probability that the first two offspring will have purple flowers?

9/16

Match the mode of inheritance with an example. 3. Epistasis

9:7 phenotype dihybrid ratio

Experimental evidence that crossing over occurs between the X chromosomes of female Drosophila was provided by _____. A) Morgan B) Bateson C) Darwin D) Punnett

A) Morgan

In a mapping experiment with three genes, which phenotype should occur most often in the F2 offspring? A) Parental Phenotypes B) All of these choices should be equal in the F2 generation. C) phenotypes of individuals with single crossover events D) phenotypes of individuals with double crossover events

A) Parental phenotypes

Match the mode of inheritance with an example. 1. Codominance

AB blood

Select the phase when the separated sister chromatids are considered independent chromosomes.

Anaphase

Why is an individual with blood type O considered a universal donor?

Because neither the A or B antigens are present on type O red blood cells

Cell division in prokaryotic cells is called ________, while in eukaryotic cells it is called ________.

Binary Fusion; Mitosis

Which of the following defines gene linkage? A) Two or more genes that are physically connected on a chromosome. B) Genes that are transmitted to the next generation as a group. C) The process by which genetic information is exchanged between homologous chromosomes. D) All of these choices are correct. E) Both two or more genes that are physically connected on a chromosome and genes that are transmitted to the next generation as a group.

Both two or more genes that are physically connected on a chromosome and genes that are transmitted to the next generation as a group.

A son has the blood-type A, genotype IAi. The father of this boy is known to be blood type AB. Which of the following is not a possible genotype for the mother? A) IAi B) ii C) IAIB D) IBi

C) IAIB

A testcross is always performed between the individual that is heterozygous for the genes to be mapped and an individual who is _____. A) heterozygous for the genes B) homozygous dominant for the genes C) homozygous recessive for the genes D) lacking the genes

C) homozygous recessive for the genes

Match the mode of inheritance with an example. 4. Pleiotropy

Cystic fibrosis

Epistasis occurs when the alleles of one gene mask the phenotypic effects of the alleles of another gene at a different locus. This phenomenon can be observed in the sweet pea, Lathyrus odoratus: C (one purple-color-producing) allele is dominant to c (white) P (another purple-color-producing) allele is dominant to p (white) cc or pp masks the P or C alleles, producing white color Determine the genotypic and phenotypic ratios of a cross between a purple and white sweet pea above. A) 9 CCPP (purple) : 7 CCPp (purple) B) 1 CcPP (purple) : 1 CCPp (purple) : 1 ccPP (white) : 1 ccPp (purple) C) 9 CCPP (purple) : 3 CcPp (purple) : 3 ccPP (purple) : 1 ccpp (white) D) 1 CCPP (purple) : 2 CCPp (purple) : 2 CcPP (purple) : 1 CCpp (white) : 4 CcPp (purple) : 2 Ccpp (white) : 1 ccPP (white) : 2 ccPp (white) : 1 ccpp (white) E) 1 CcPP (purple) : 1 CcPp (purple) : 1 ccPP (white) : 1 ccPp (white)

E.

Mendel chose peas to study because they naturally outcross to each other. If self-fertilization was required, special steps could be taken to perform that cross as well.

False

A Y-linked gene is passed from?

Father to son

You discover a new species and name the sex chromosomes C and D. You've determined that the C chromosome doesn't appear in males. If the female is heterogametic and the male is homogametic, then what would be the chromosome arrangement of sex chromosomes in the adult?

Female CD, Male DD

Match the mode of inheritance with an example. 5. Incomplete dominance

Four O'Clock flower color

A plant that is homozygous dominant for the tall trait is crossed with a plant that is heterozygous for the tall trait. What are the expected genotypic and phenotypic ratios of the offspring?

Genotype—50% TT : 50% Tt; Phenotype—100% tall

In each species, the number of linkage groups equals the _________________ number of chromosome types. A) genetic map B) Syntetic C) genetic linkage D) linkage group E) Haploid

Haploid

A son has the blood-type B (IBi). The father of this boy is known to be blood type AB. In order for the son to donate blood to his mother, what must be the mother's genotype? A) IBi B) IAi C) IAIB D) ii

IBi

Two genes that are located on the same chromosome are said to be _____. A. linked B. recombinant C. parental-like D. nonparental-like

Linked

The location of a gene on a chromosome is called its _____________.

Locus

Which of the following statements about crossing over is TRUE? A) It occurs only in some chromosomes. B) It occurs only between genes that are heterozygous. C) It occurs only in males. D) None of these choices are correct. E) It results in reduced genetic variation among gametes.

None of these choices are correct.

If a person is blood type O and needs a transfusion, which of the following blood types could act as a donor? A) B B) O C) A D) AB

O

In a mapping experiment with three genes, which phenotype should occur most often in the F2 offspring? A. parental phenotypes B. phenotypes of individuals with single crossover events C. phenotypes of individuals with double crossover events D. All of these choices should be equal in the F2 generation.

Parental Phenotypes

Select the phase when the nuclear membrane starts to disassociate.

Prophase

Which of the following indicates the correct order of these events?

Prophase - Prometaphase - Metaphase - Anaphase - Telophase

Match the mode of inheritance with an example. 2. Overdominance

Sickle cell anemia

Two or more genes that are located on the same chromosome are _______________ A) genetic map B) Syntetic C) genetic linkage D) linkage group E) Haploid

Syntetic

Select the phase when the nuclear membrane re-forms around the chromosomes.

Telophase

The individual who is credited with discovering genetic linkage in Drosophila is _____. A. Thomas Hunt Morgan B. Gregor Mendel C. Alfred Sturtevant D. Barbara McClintock

Thomas Hunt Morgan

The process of recombination may rarely occur during mitosis. (T or F)

True

Crossing over occurs during prophase I of meiosis? True False

True, Crossing over does occur during prophase 1 of meiosis

The locus is the physical place of a gene on a chromosome? (T or F)

True- locus

In the AB blood phenotype, neither of the alleles responsible for the antigens are dominant over the other. (T or F)

True.

Epistasis is _______________.

When one gene can mask the expression of a second gene

A researcher hypothesized that two genes were following Mendel's laws, and performed a test. The two genes produced four allele combinations in the progeny. Applying the chi square formula to the results gave a chi square value of 0.352. Looking at the chi square table, the researcher should ______ the hypothesis since values equal to or greater than 0.352 are expected to be seen ______ of the time based on random chance alone.

accept; 95%

Genes are physically located within ______.

chromosomes

In a certain family pedigree, you observe that 7 of a couple's 12 children display a disease trait. In the subsequent generation, some of the children of affected individuals have the disease, but none of the children of two unaffected parents do. You conclude that the disease is caused by a ______ allele.

dominant

In a certain family pedigree, you observe that 7 of a couple's 12 children display a disease trait. In the subsequent generation, some of the children of affected individuals have the disease, but none of the children of two unaffected parents do. You conclude that the disease is caused by a ______ allele. A. redundant B. recessive C.dominant D.Correct E. wild-type

dominant

In rabbits, full coat color (C ) is the dominant trait. A second allele, chinchilla (c ch ), is recessive to full coat color. Himalayan coat color (c h ) is recessive to chinchilla and full coat colors, and albino (c ) is recessive to all coat colors. If two chinchilla rabbits mate, what coat color is not possible in their offspring? A. full coat color B. chinchilla coat color C. himalayan coat color D. albino coat color E. All coat colors are possible.

full coat color

Mendel's law of independent assortment states that ______ randomly assort their ______ during the formation of haploid cells.

genes; alleles

When genes that are close together on the same chromosome are transmitted as a unit it is called _________________ ________________ A) genetic map B) Syntetic C) genetic linkage D) linkage group E) Haploid

genetic linkage

A diagram that depicts the sequence of genes along a chromosome is called a ________________ ________ A) genetic map B) Syntetic C) genetic linkage D) linkage group E) Haploid

genetic map

Sickle-cell disease in humans is an example of ______. A. codominance Incorrect B. incomplete penetrance C. heterozygote advantage D. sex-limited resistance

heterozygote advantage

Mendel's work with two-factor crosses led directly to which of the following?

law of independent assortment

In the biological sciences, the hypothesis is usually rejected if the P value is _____.

less than 0.05

An entire chromosome is considered a _______________ ____________, as it contains a group of genes that are physically linked together. A) genetic map B) Syntetic C) genetic linkage D) linkage group E) Haploid

linkage group

Another name for a chromosome is a _______, since it contains genes that are often inherited together. A. linkage group B. crossing over group C. genetic recombinant D. bivalent

linkage group

Organelles are __________.

membrane-bound compartments in eukaryotic cells.

If an allele is dominant in one sex and recessive in another, it is an example of ___________.

sex-influenced inheritance

A tetrad is made up of _____? A) two homologous chromosomes, each consisting of two chromatids B) four nonhomologous chromosomes C) four homologous pairs of chromosomes D) four nonhomologous chromatids

two homologous chromosomes, each consisting of two chromatids