Inheritance Patterns

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The phenotype of a guinea pig’s hair color can best be determined by

a. Test crossb. Looking at the guinea pigc. Pedigree chartd. Knowing the genotype of the mother pig

If a trait that is visible in the parent organisms is not seen in the offspring but then returns in the F2

generation, the most probable cause is that this trait in question is

a. Recessiveb. Dominantc. Codominantd. Mutated

Which of the following genotypes below shows a pure dominant genotype?

a. Aab. aac. AAd. AB

Genes that are located at the same position on homologous chromosomes are called

• Recessive• Dominant• Alleles• Homozygotes

In garden pea plants, the offspring formed from a cross between two heterozygous

tall parents would most likely be • 25% tall• 50% tall• 75% tall• 100% tall

A pink flower is produced by crossing a plant that has white flowers with a plant that has red flowers. This

example most likely shows what condition in genetics?

• Incomplete dominance• Codominance• Dominance• Recessive trait

Who was Gregor Mendel?

• Gregor Mendel was a monk who grew pea plants to study genetics

What is the difference between a dominant allele and a recessive allele?

• Dominant allele – capital letter• Recessive allele – lowercase letter

The parents of three girls are expecting another child, what are the chances the child will be a boy?

• 25% • 50%• 75%• 100%

If an colorblind man and a woman who is a carrier for colorblindness have a child, what

percentage of their female children will be color-blind?

• 0% • 25%• 50%• 100%

Which of the following would represent the sex chromosomes of a normal female?

• XX• XY• YY• XXY

Match the genetic cross of the parents on the left with the genotypes on the right of the offspring most likely

to be produced from that cross. You may use an answer choice more than once or not at all.

Genetic Cross1. BB x bb2. Bb x Bb3. BB x BB4. bb x bb5. Bb x bb

Predicted Offspringa. 25% BB 50% Bb 25% bbb. 100% bbc. 100% Bbd. 50% Bb 50% bbe. 100% BBf. 75% Bb 25% bb

Match the genetic cross of the parents on the left with the phenotypes on the right of the offspring most likely

to be produced from that cross. You may use an answer choice more than once or not at all.

Genetic Cross1. TT x tt2. tt x Tt3. Tt x Tt4. TT x TT5. tt x tt

Predicted Offspringa. 100% shortb. 75% tall 25% shortc. 100% talld. 25% tall 75% shorte. 50% tall 50% short

What organisms did Mendel use in his famous genetic experiments?

• Mice• Pea plants• Rose plants• Horses

What would be the expected phenotypes of the offspring from the following cross?

(TT x Tt)a. 50% tall, 50% shortb. 100% tallc. 100% shortd. 75% tall, 25% short

What is the name given to a particular cross used to determine the unknown genotype of an

organism?a. Test crossb. Homologous crossc. Heterozygous crossd. Target cross

In humans, skin color is controlled by at least four genes, this is an example of

a. Sex-linked traitb. Recessive traitc. Polygenic traitd. Codminant trait

A female that has an allele for color blindness but not the phenotype for color

blindness would be considereda. Color-blindb. A carrier for color blindnessc. Homozygous dominant for color blindnessd. Homozygous recessive for color blindness

If a human male that is heterozygous for blood type B has a child with a woman who is heterozygous for

blood type A, what percent of their children can be expected to have blood type B?

a. 25%b. 50%c. 75%d. 100%

In Mendel’s first experiment, true-breeding plants with contrasting forms for one trait were crossed. Only one form appeared in the hybrid F 1 offspring. What did

this show? • [A] one inheritable unit (element) came from

each parent • [B] one form was dominant over the other • [C] the parents were not true breeding • [D] the traits separate during gamete

formation

After the first experiment described above, Mendel then self-pollinated the F 1 generation and obtained an F 2 generation with both parental forms in the ratio of

3 to 1. What additional information did this show? • [A] the traits separate during gamete

formation• [B] one inherited unit came from each parent • [C] the parents were not true breeding • [D] one form was dominant over the other

How would you describe the P and F 1 plants in Mendel’s first experiment in

modern terms? The P plants were • [A] heterozygous as were the F 1 plants • [B] homozygous as were the F 1 plants • [C] heterozygous and the F 1 plants were

homozygous • [D] homozygous and the F 1 plants were

heterozygous

Today geneticists refer to Mendel’s true-breeding parent pea plants as

• [A] codominant for the traits • [B] dominant for the traits • [C] homozygous for the traits • [D] heterozygous for the traits

An individual’s genotype for an inherited trait is the

• [A] set of alleles carried for the trait • [B] family pedigree for the trait • [C] sex of the individual in relation to the trait • [D] physical appearance caused by the trait

Hybrid means the same as

• [A] homozygous • [B] dominant • [C] mutant • [D] heterozygous

A gene whose effect remains hidden when it is paired with a different gene is called

• [A] mutant • [B] recessive • [C] codominant • [D] dominant

Different genes that affect the same single trait are called

• [A] alleles • [B] genes • [C] chromosomes • [D] hybrids

An individual in which the two alleles of a pair that affect a particular trait are identical is said to be

• [A] heterozygous • [B] hybrid • [C] homozygous • [D] dihybrid

The genetic makeup of an individual for a trait being studied is called that individual’s

• [A] phenotype • [B] pedigree • [C] genotype • [D] variability

Let’s say that “A” represents the gene for a dominant characteristic and “a” its recessive allele. If an Aa

individual mates with an aa individual

• [A] all offspring will show recessive trait • [B] half the offspring will show the dominant

trait and half will show the recessive trait • [C] three quarters of the offspring will show

the dominant trait and one quarter will show the recessive trait

• [D] all offspring will show the dominant trait

How many heterozygous offspring would you expect if two parents who were heterozygous for a trait produced an F 1 generation of 40 individuals?

• [A]5• [B] 10 • [C] 15 • [D] 20

Human blood type is determined by

• [A] polygenic inheritance • [B] a single gene • [C] linked gene pairs • [D] multiple alleles

What is the relationship between two unlike alleles of a pair if they both express their effects on an individual’s phenotype? • [A] codominance • [B] linkage • [C] X-linkage • [D] dominance

The relationship between the IB allele for Type B blood and the i allele for Type O blood is

• [A] codominance • [B] different loci • [C] dominant/recessive • [D] unknown

In the AB blood type, the relationship between the IA allele and the IB allele is

• [A] X-linked • [B] dominant/recessive • [C] codominance • [D] unknown

Mr. Sandival has Type B blood. Mrs. Sandival has Type O blood. They have three children of their own and one adopted child. Owen has Type AB blood, Mary Type O, Susie Type B, and Carl Type B. Which child is adopted?• [A] Susie • [B] Owen • [C] Mary • [D] Carl

A homozygous clover with a “v-shaped” leaf pattern is crossed with a homozygous clover that has a large pale center to its

leaves. The leaves of every plant in the F1 generation show a v-shaped pattern on a large pale center (expressing characteristics

of both parents). This is an example of • [A] segregation • [B] breeding • [C] mutation • [D] codominance

Identification bracelets were accidentally removed from three newborn babies. Blood samples were taken to

help the identification procedures. The blood types for the babies and their parents were

• Baby I—Type A Baby II—Type O Baby III—Type AB• Mr. Black—Type A Mr. Brown—Type AB Mr. White—Type O• Mrs. Black—Type B Mrs. Brown—Type O Mrs. White—Type O• Which baby could belong to Mr. and Mrs. Black?

– [A] Baby I – [B] Baby II – [C] Baby III – [D] any of the three

• Which baby could belong to Mr. and Mrs. Brown? – [A] Baby I – [B] Baby II – [C] Baby III – [D] any of the three

• Which baby could belong to Mr. and Mrs. White? – [A] Baby I – [B] Baby II – [C] Baby III – [D] any of the three

Use the following information to answer the questions.

• In peas, yellow seed (Y) is dominant to green seed (y), and round seed (R) is dominant to wrinkled (r).

• How many types of gametes could be produced by a YYRr plant? – [A]1– [B]2– [C]3– [D]4

• How many types of gametes could be produced by a YyRr plant?– [A]1– [B]2– [C]3– [D]4

• How many types of gametes could be produced by a yyRR plant, the most common garden variety of pea?– [A]1– [B]2– [C]3– [D]4

If AaBb is crossed with aabb, what proportion of the offspring would be expected to be aabb?

a. 9/16b. 1/8c. 1/4d. 1/16

If the offspring of a cross show a 9/16 to 3/16 to 3/16 to 1/16 ratio (9:3:3:1), the parents of the cross have the genotypes

a. AaBb x AaBbb. AaBb x aaBBc. aaBb x aabbd. aaBb x Aabb

If W = purple flower and w = white, and D = tall plants and d = short plants, a wwDd plant would be

a. purple and tallb. purple and shortc. white and talld. white and short

If aaBb is crossed with AAbb, what proportion of the offspring will be Aabb?

a. 1/2b. 3/16c. 9/16d. 1/4

In Summer Squash, the allele for white fruit (W) is dominant over that for yellow fruit (w). Similarly, the allele for disk-shaped fruit (D) is dominant over

that for sphere-shaped fruit (d). The Punnett square below shows a cross between two squash plant with genotype ‘WwDd’. How many offspring will

have yellow disk-shaped fruits?

a. 9b. 3c. 2d. 1

In guinea pigs, the allele for black fur (B) is dominant over that for brown fur (b). Similarly, the allele for short fur (S) is dominant over that for long fur (s). The Punnett square below shows a cross between two guinea pigs with the genotype ‘BbSs’. What is the phenotypic outcome of the offspring produced

by this cross?a. 13 Black short fur, 1 Black long

fur, 1 Brown short fur, 1 Brown long fur

b. 12 Black short fur, 1 Black long fur, 1 Brown short fur, 2 Brown long fur

c. 4 Black short fur, 4 Black long fur, 4 Brown short fur, 4 Brown long fur

d. 9 Black short fur, 3 Black long fur, 3 Brown short fur, 1 Brown long fur

What phenotypes and phenotypic ratios would you expect in a test cross of a pink flowered and

a red flowered snapdragon?a. 1 white: 2 pink: 1 redb. 3 red: 1 pinkc. 1 red : 1 pinkd. 2 pink: 1 rede. 3 pink: 1 red

If a pedigree shows that a human trait seems to skip generations the trait is probably

__________.a. Sex linkedb. Polygenicc. Dominantd. Recessive

In this pedigree, the shaded individuals are homozygous recessive. What is the genotype of

individual B?a. heterozygousb. homozygous recessivec. homozygous dominantd. none of the abovee. can not tell from the diagram

What type of inheritance mechanism—dominant, recessive, or sex-lined recessive—is shown in the pedigree? Support your answer with evidence.

• Recessive because it skips a generation and is present in both males and females

What type of inheritance mechanism—dominant, recessive, or sex-lined recessive—is shown in the pedigree? Support your answer with evidence.

• Recessive because it skips a generation and is present in both males and females

What type of inheritance mechanism—dominant, recessive, or sex-lined recessive—is shown in the pedigree? Support your answer with evidence.

• Sex linked recessive because only males are affected. Mothers of affected males are most likely carriers.

What type of inheritance mechanism—dominant, recessive, or sex-lined recessive—is shown in the pedigree? Support your answer with evidence.

• Dominant because the trait is present in each generation.

A female whose father was red-green colorblind marries and normal male whose father was also red-

green colorblind. What is the probability that their son will be colorblind?

a. 0%b. 25%c. 50%d. 75%

*Remember red-green colorblindness is a sex-linked recessive trait.

A female whose father was colorblind marries and normal male whose father was also colorblind. What is the probability that their daughter will be colorblind?

a. 0%b. 25%c. 50%d. 75%

*Remember red-green colorblindness is a sex-linked recessive trait.

A woman whose brother has hemophilia is concerned about passing this trait to her offspring. What is the risk

that she will have a son with hemophilia?

a. 1/8b. ¼c. ½d. 100%

*Remember hemophilia is a sex-linked recessive trait.

Can a male be a carrier for a sex-linked disease?

a. yes, if the trait is recessiveb. yes, if the male's father and mother were

carriersc. no, males have only a single copy of sex-

linked genesd. no way to predict

Achondroplasia is a dominant inherited disorder that causes a form of dwarfism. The homozygous dominant condition for this allele is lethal. If one parent is an achondroplasic dwarf, and the other parent is of normal height, then what proportion of their

children will be expected to be of normal height?a. Allb. ½c. ¼d. Nonee. 3/4

If a woman who is red-green color blind marries a man with normal vision, what phenotypes

would you expect their children to have?a. All their daughters will be carriers and all their sons

will be color-blind.b. All their daughters will be color-blind, but all their

sons will have normal vision.c. All their daughters will have normal vision and will

not be carriers, but all their sons will be color-blind.d. Half of their daughters will be carriers and the other

half will be fully normal, half of their sons will be color-blind and the other half will have normal vision.

e. All their children will be color-blind

In 1944 Charlie Chaplin was involved in a legal battle over the paternity of a child born to Joan Berry, a young starlet. The baby was blood type B, the mother A, and Chaplin O. From what you know about inheritance of blood types, could Chaplin

have been the father of the child? (At the time of the trial, blood group evidence was not admissible in California courts. Charlie Chaplin was declared responsible for the

child's support).

a. If Chaplin's blood was B, then he must be the father.

b. No, he could not possibly have fathered the child.

c. Yes he could of fathered the child.d. Perhaps, these results are inconclusive.