Bio 111 chapter 12 hw 2

The physical basis for the independent assortment of alleles when gametes are formed is

the independent alignment of homologous pairs during metaphase I.

Pedigrees are useful to geneticists because they can help determine: Check all that apply.

the mode of inheritance for a particular trait. the genotype of a particular individual. the probability that future offspring will inherit a particular trait. whether a particular trait is dominant or recessive.

Before Mendel's experiments with pea plants, which ideas formed the basis for most thinking about heredity? Check all that apply.

the traits of both parents are blended together in their offspring heredity occurs within species traits are transmitted directly from parents to offspring

Mendel used the garden ___ plant for his studies on inheritance.

pea

A Punnett square is generally used to

predict the genotypic ratio among the offspring.

What is the probability that a mother with type A blood and genotype IAi and a father with type AB blood will produce a child with AB blood

0.25

A and B are independent events. The probability that A will happen is 1/4 and the probability that B will happen is also 1/4. What is the probability they will both happen?

1/16

If you are tossing a six-sided die, what is the probability of getting either a 3 or a 4 on your third toss AND a 6 on your fourth toss?

1/18

In mice, the allele for black fur is dominant to the allele for brown fur. If a male homozygous black mouse is crossed with a female brown mouse, what proportion of the black F2 offspring do you predict will be homozygous?

1/3

In rabbits there is a dominant gene "T" for long ears and its recessive allele "t" for short ears. At another gene locus, there are alleles "B" for black coat and "W" for white coat. Neither allele is dominant nor BW produces a gray coat. These two allele pairs assort independently. If a gray rabbit that is heterozygous at the gene locus controlling ear length is mated with a white rabbit that is also heterozygous at the gene locus controlling ear length, what proportion of the long-eared offspring will be homozygous for that trait?

1/3

Achondroplasia is a common form of dwarfism caused by an autosomal dominant mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. Two copies of the mutant gene are invariably fatal before or shortly after birth. If a person with achondroplasia marries a person of normal height, what is the probability that both their first child and second child will have achondroplasia?

1/4

Let Y = yellow and y = green, and R = round and r = wrinkled. You cross YYRR peas with yyrr peas. All of the F1 individuals are yellow and round with a genotype of YyRr. You then perform an F2 cross and get the expected 9:3:3:1 phenotypic ratio. What proportion of the F2 plants are expected to be heterozygous for both traits?

1/4

Consider the cross AaBbCcddEe X AABBccDDEe. If these 5 allele pairs all assort independently, then the probability that any individual offspring will have the genotype AABBccDdEe is 1 out of

16

In snapdragons, there is one allele that produces red flowers and another allele that produces white flowers. Neither allele is dominant and heterozygous individuals have pink flowers. A plant breeder decides to cross a white flowered snapdragon with a pink flowered snapdragon. What is the expected phenotypic ratio among the offspring?

1:1

The genotypic ratio produced in the F2 generation is most likely

1:2:1.

At one gene locus in humans there are 2 alleles: one for curly hair and another for straight hair. Neither allele is dominant, and heterozygous individuals have wavy hair. At a second gene locus, 3 alleles control ABO blood type. The alleles at these 2 gene loci assort independently. A man with straight hair and A blood marries a woman with wavy hair and B blood. Their first child has straight hair and O blood. If their second child is a boy with straight hair, what is the probability that he has A blood? ( Express your answer as a percentage. Enter the number only without the percent sign. For example, enter 100% as 100 and enter 12.5% as 12.5 )

25

If two people who both have blood type AB get married, what is the probability that their second child will have blood type A? ( Express the probability as a percent. Enter the number only without the percent sign. For example, enter 100% as 100 and enter 12.5% as 12.5 )

25

In rats, the allele for long whiskers is dominant to the allele for short whiskers. At another gene locus, a dominant allele produces whiskers and the recessive allele produces a rat with no whiskers. The alleles at these 2 gene loci assort independently. If a rat that is homozygous for both recessive alleles is crossed with a rat that is heterozgous at both gene loci, what percentage of the offspring are expected to have short whiskers? ( Enter the number only without the percent sign. For example, enter 100% as 100 and enter 12.5% as 12.5 )

25

In watermelons, the gene for green color is dominant over its allele for striped color. At another gene locus, the gene for short shape is dominant over its allele for long shape. These two allele pairs assort independently. If a plant with long, striped fruit is crossed with a plant that is heterozygous for both of these traits, what percentage of the offspring do you expect will be short and green? ( Enter the number only without the percent sign. For example, enter 100% as 100 and enter 12.5% as 12.5 )

25

In pea plants, the allele for round seeds is dominant to the allele for wrinkled seeds. At another gene locus, the allele for yellow seeds is dominant to the allele for green seeds. These two allele pairs assort independently. If a plant breeder crosses two plants that are both heterozygous at both gene loci, what proportion of the offspring will produce round, green seeds?

3/16

In rabbits, there is a dominant gene "T" for long ears and its recessive allele "t" for short ears. At another gene locus, there are alleles "B" for black coat and "W" for white coat. Neither allele is dominant nor BW produces a gray coat. These two allele pairs assort independently. If a gray rabbit that is heterozygous at the gene locus controlling ear length is mated with a white rabbit that is also heterozygous at the gene locus controlling ear length, what is the probability that their first offspring will be gray with long ears?

3/8

Consider the cross AaBbCcddEe X AABBccDDEe. If these 5 allele pairs all assort independently, then the probability that any individual offspring will have the genotype AaBBCcDdEE is 1 out of

32

In mice, the allele for black fur is dominant to the allele for brown fur. If a male heterozygous black mouse is crossed with a female brown mouse, what percentage of the F1 offspring do you predict will be homozygous? ( Enter the number only without the percent sign. For example, enter 100% as 100 and enter 12.5% as 12.5 )

50

A male fruit fly has the genotype AaPpYYrrTt. In terms of these 5 allele pairs, how many different types of gametes can he form?

8

A woman with blood type O has a child with blood type O. She claims that a man named Ralph is the child's father. Her claim would be proven false if Ralph has blood type: Check all that apply.

AB

Parent Blood Types A and B A and A B and O Child Blood Type O B AB Three babies were recently mixed up in a hospital. Based on the data in the table above, the couple with blood types B and O are the actual parents of the child with blood type

B

When type B blood is given to a person with type A blood

B antigen from the donor reacts with anti-B antibody in the recipient.

The seven traits that Mendel studied in pea plants have a relatively simple pattern of inheritance. Since the time of Mendel, however, scientists have discovered many traits that have more complex patterns of inheritance. Which of the following elements from Mendel's model of inheritance turned out to be oversimplifications that aren't true for many traits? Check all statements that are oversimplifications.

Each trait in an organism is controlled by one pair of alleles At each gene locus there are two possible alleles, one that is dominant and one that is recessive Each pair of alleles controls one trait

Mendel succeeded in discovering the basic laws of inheritance while many people before him had failed. Which of the following contributed to his success? Check all that apply.

He simplified the problem by looking at only one or two traits at a time He focused on traits that existed in two easily distinguishable forms He chose an organism where many pure varieties were available He chose an organism that was easy to grow and that had a short generation time He chose an organism where many pure varieties were available He chose an organism that was easy to grow and that had a short generation time He chose an organism where he could easily control whether self-fertilization or cross-fertilization took place

A mother with type A blood and genotype IAi and a father with blood type B and genotype IBi have children who grow up and become regular blood donors. Of the possible children, which genotype would have the least valuable blood to donate?

IAIB

A person with type B blood can receive blood from people with which allele combinations

IBi

In humans, brown eyes are dominant to blue eyes. If a blue-eyed man marries a brown-eyed woman whose mother has blue eyes, what percentage of the brown-eyed offspring do you expect will be heterozygous? (Enter the number only without the percent sign. ( For example, enter 100% as 100 and enter 12.5% as 12.5 )

`100

Alternate forms of the same gene are called

alleles.

People with type AB blood have

both type A and type B antigens on their red blood cells.

If you crossed flies heterozygous for the Cy allele, what phenotypes would you find in the adult F1 generation?

both wild type and curly wings

You are tossing a six-sided die. Because you cannot roll both a 2 and a 5 on a single toss, these two events are called

mutually exclusive

In modern terminology, Mendel's heredity "factors" are called

genes.

You toss a coin twice. Because the outcome of the first toss does not affect the outcome of the second toss, these 2 events are called

independent.

An allele for a particular trait that is only expressed in the presence of a second copy of the same allele is called

recessive.

Mendel used the ______ to determine whether an individual with the dominant phenotype was homozygous or heterozygous for that trait.

testcross

According to Mendel's Principle of Segregation

the two alleles at each gene locus separate during gamete formation