Heredity
Hemophilia is an X-linked recessive disorder (Xh) that is passed through generations and can be traced by using a pedigree. mc018-1.jpg What is the probability that a female child of Charles and Marie would suffer from hemophilia?
0 percent
Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. What is the probability of having offspring that have wrinkled seeds and yellow seed color for the cross RRYY ´ RrYy?
0 percent
In roses, red flowers and long stems are dominant traits. A rose plant that is homozygous for both red flowers and long stems is crossed with a rose plant that is heterozygous for red flowers and homozygous for short stems. What percentage of the offspring will exhibit red, long-stemmed flowers?
100 percent
When Mendel crossed purebred purple flowering plants (PP) with purebred white flowering plants (pp), what were the flower colors of the resulting offspring?
100 percent purple
The diagram represents a dihybrid cross between two pea plants heterozygous for both seed color and seed shape. mc021-1.jpg What is the phenotypic ratio of the offspring?
1:3:3:9
Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. An incomplete dominance cross is performed between a bird that is homozygous for red feathers and a bird that is homozygous for blue feathers. Purple offspring result. Then, two of the purple offspring are crossed. According to the Punnett square for this cross, how many of the offspring from the second cross will have a feather color that results from incomplete dominance?
2 in 4
Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. Cats that have coats that are a patchwork of black and orange are called tortoiseshell cats, are typically female, and have genes that code for both black fur (Xo) and orange fur (XO) located on the X chromosomes. Y chromosomes do not code for color in tortoiseshell cats. A female cat that has only orange fur (XOXO) is crossed with a male cat that has only black fur (XoY). mc013-1.jpg How many of the offspring will exhibit tortoiseshell coloring?
2 in 4
The table below summarizes Mendel's results for the F2 generation. Mendel's Results Plant height 787 tall 277 short Flower color 705 purple 224 white Flower position 651 middle of stem 207 end of stem Pod color 428 green 152 yellow Pod shape 882 inflated 299 constricted Seed color 6,022 yellow x green Seed shape 5,474 smooth 1,850 wrinkled What number should replace the letter x in the "Seed color" row?
2,001
When plants that are heterozygous for round seeds are crossed, what is the probability that the offspring will have wrinkled seeds?
25 percent
A plant can produce either purple flowers or white flowers. What is the probability of purple-flowered offspring if two plants that are heterozygous for purple flowers are crossed?
3:4
In peas, yellow seed color (Y) is dominant to green seed color (y). A homozygous green pea plant is crossed with a heterozygous yellow pea plant. What is the predicted phenotypic ratio of the offspring?
50 percent Yy, 50 percent yy
Tall pea plants are dominant over short pea plants. If there are 200 short plants in the F2 generation from a cross that followed Mendel's methods, about how many plants will be tall in that generation?
600
A dihybrid cross is created from plants that are heterozygous for both round seeds and yellow seed color. What is the ratio of offspring that have round seeds and yellow seed color?
9:16
A plant that has round and yellow seeds (RrYy) is crossed with a plant that has round and yellow seeds (RrYy). What is the ratio of the offspring that will have round and yellow seeds? Key: R = round r = wrinkled Y = yellow y = green
9:16
In a dihybrid cross for round and yellow seeds (RrYy x RrYy), what is the probability of having green and wrinkled seeds? Key: R = round r = wrinkled Y = yellow y = green
9:16
If you inherit the genotype AO for blood from your parents, what blood type do you have?
A
Which statement describes Mendel's hypotheses regarding gametes?
A gamete carries one allele for a gene.
Why is it important to know a person's rhesus factor before a blood transfusion?
A patient who is Rh- can receive only Rh- blood.
Mary has type A blood. Her son Bill has type AB blood. Which blood type does Bill's dad have if he is homogenous for blood type?
B
Which of Mendel's generations was allowed to self-pollinate?
F1 generation
Hemophilia is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree. mc015-1.jpg Who has hemophilia in the pedigree that is shown?
Fred and Luke
Pedigrees are used to help geneticists understand how traits are inherited between generations. The Romanovs, a Russian royal family, had a history of hemophilia, a sex-linked disorder that is determined by a recessive allele on the X chromosome. mc014-1.jpg What is the best evidence to prove that Irene was heterozygous for hemophilia?
Frederick has the recessive allele.
Which statement summarizes the law of segregation?
Gametes carry one allele for each trait.
What can be known about Mendel's five-part hypothesis?
It is an answer to a scientific question and is based mostly on research.
Which was most likely an effect on society that resulted from improvements in blood handling during World War I and World War II?
More soldiers who had lost a limb returned home.
How did the discovery of the rhesus factor affect society?
New treatments during pregnancy could prevent harm to the developing child.
The concept of evolution by way of natural selection is a central tenet in biology that has been tested in numerous ways by many scientists but is not yet considered a law. Evolution by way of natural selection is most likely which type of concept?
Not a likelihood based on the chance that a particular event will or will not occur
Hemophilia is an X-linked recessive disorder. mc005-1.jpg What is the probability of having hemophilia for the cross that is shown in the Punnett square?
Not 25 percent
Duchenne muscular dystrophy is an X-linked recessive disorder. mc009-1.jpg What is the probability that a female offspring of the cross that is shown above would have a recessive allele for Duchenne muscular dystrophy disorder?
Not 50 percent
Which statement best describes human eye color?
Not an incompletely dominant trait that follows Mendelian inheritance patterns
If a person has type B blood, which statement describes the antibodies present in his or her blood?
Only anti-A antibodies are present.
If Mendel had crossed a true breeding dominant plant with a true breeding recessive plant, in which of the three generations is the recessive trait visible?
P generation and F2 generation
Mendel crossed two plants that were heterozygous for purple flower color. Which genotypes could he have used to represent the cross?
Pp*Pp
Pedigrees help geneticists understand how traits are inherited between generations. Red-green color blindness is a sex-linked disorder that is determined by a recessive allele on the X chromosome. mc024-1.jpg If Brian has a son who is color-blind, what is known about the genotype of the son's mother?
She must have at least one allele for color blindness.
John and Pat are identical twins with identical DNA. John works in a movie theater, and Pat works as a lifeguard. They have very different skin pigmentation. Which is the best explanation of the difference?
Skin color, a polygenic trait, is also determined by environmental factors.
Which statement best describes an understanding of genetics that would be missing without the work of Mendel?
Some alleles are dominant, and some alleles are recessive.
The offspring of a particular cross are 100 percent heterozygous for tallness. What were the most likely genotypes of the parents?
TT*tt
Gregor Mendel crossed homozygous tall plants (TT) with homozygous short plants (tt). All the resulting offspring were tall. From these results, what conclusion did Mendel draw?
Tallness is a dominant trait.
A scientist is studying fruit fly wings. Straight wings are dominant, and curly wings are recessive. Which statement correctly describes the F1 generation if a straight-winged parent is crossed with a curly-winged parent and if both parents are true breeding?
The offspring will have one allele for straight wings and one allele for curly wings.
A pea plant exhibits a recessive trait. Which statement is most likely true about the plant?
The plant has two identical alleles for the gene that codes for the trait.
During an experiment, a scientist crosses a pea plant that has purple flowers with a pea plant that has white flowers. The plants that result from this cross in the F1 generation have both purple and white flowers. What can the scientist conclude?
The plants in the P generation were not true-breeding.
Some people have freckles, and some people do not have freckles. If a child has freckles, at least one parent has freckles. However, the child may have a sibling that does not have freckles. Which statement best describes the presence of freckles?
There are two alleles for freckles.
The table below summarizes the traits that Mendel examined during his experiments. Traits Studied by Mendel mc005-1.jpg What do these characteristics all have in common?
They can all be easily observed.
Scientists often use fruit flies as a method to test hypotheses about human genes. Why are fruit flies advantageous in the study of human inheritance?
They reproduce quickly and take up little space.
Why did Mendel study pea plants?
They reproduce sexually and have many traits that are easy to observe.
Why did Gregor Mendel study pea plants?
They reproduce sexually.
Which is the best example of a hypothesis leading to new experimental methods?
Thomas Hunt Morgan continued the genetic research of Gregor Mendel, but Morgan used fruit flies
Gregor Mendel used pea plants that were heterozygous for each of two traits—seed color and seed shape—to generate a dihybrid cross. The phenotypic ratio of the resulting offspring was nine with round and yellow seeds, three with round and green seeds, three with wrinkled and yellow seeds, and one with wrinkled and green seeds. From these results, what could Mendel conclude?
Traits are passed independently of one another.
Mendel was able to study seven traits in all the pea plants in each generation. Which of his hypotheses allowed him to analyze each trait separately?
When gametes are formed, each gamete carries only one allele for the gene.
Which of Thomas Hunt Morgan's hypotheses was valid?
White eyes are homozygous recessive in female Drosophila.
Which allele combination represents a female who has a heterozygous sex-linked trait?
XRXr
Which allele combination represents a male who has an X-linked recessive disorder?
XRXr
What is genotype for a recessive trait found on the female chromosome?
Xh
Hemophilia is an X-linked recessive disorder that is passed through generations and can be traced by using a pedigree. mc023-1.jpg In the pedigree that is shown, which represents Irene's allele combination?
XhXh
A purebred plant that has yellow flowers is crossed with a purebred plant that has white flowers. All the offspring have yellow flowers. Which conclusion about yellow flowers is supported by these results?
Yellow flower color is a dominant trait.
Which represents the cross between parent plants if one is heterozygous for yellow-colored pods and the other is homozygous for green-colored pods?
Yy ´ yy
Glaucoma is a leading cause of blindness. Studies have linked a common form of glaucoma to three genes and more than 20 genetic loci. Which best describes glaucoma?
a dominant trait that depends on the presence of only one of many dominant alleles
What is a gene?
a segment of DNA that is the basic unit of heredity
Which was not a result of the 1898 discovery of the four blood types?
all blood types made compatible with each other
Which are different forms of the same gene?
alleles
Which combination of alleles best describes a sex-linked trait?
alleles that are carried on X and Y chromosomes
A purebred purple flowering plant is crossed with a purebred white flowering plant, and they produce offspring that have purple flowers. Which is the trait for purple flowers?
dominant
Mendel's pea plants had either purple or white flowers. This means that the plants
have two alleles for the gene.
Which describes the notation Tt for the trait of being tall?
heterozygous genotype
The image shows a purple sweet pea that is labeled with its two alleles for petal color. mc021-1.jpg Which is the genotype of the sweet pea?
homozygous dominant
The Punnett square predicts the ratio of genotypes in the offspring based on the genotypes of the parents. Which Punnett square represents a cross between a mom who is heterozygous for dimples and a dad who is homozygous for no dimples?
http://media.edgenuity.com/evresources/3209-06-02/mc008-2.jpg
Round seeds and yellow seed color are dominant to wrinkled seeds and green seed color. Which Punnett square represents the correct way to set up the cross RRYy ´ RrYY?8
http://media.edgenuity.com/evresources/3209-06-02/mc012-3.jpg
Which Punnett square represents a cross between two parents that are heterozygous for purple flowers?
http://media.edgenuity.com/evresources/3209-06-03/mc006-1.jpg
Drosophila eye color is an X-linked trait. Red eye color is dominant, and white eye color is recessive. Which Punnett square shows the probability that 100 percent of offspring will have red eyes?
http://media.edgenuity.com/evresources/3209-06-07/mc007-1.jpg
Which pedigree symbol is used to represent a female carrier of a recessive X-linked trait?
http://media.edgenuity.com/evresources/3209-06-07/mc020-2.jpg
Which type of scientific statement is defined as "a possible explanation or answer to a scientific question that is based on prior knowledge or research and is testable"?
hypothesis
Some flowering plants appear to have offspring that have traits that are intermediate between those of the parents. Which type of dominance is exhibited by the offspring?
incomplete dominance
Which inheritance pattern results when parents are crossed for pure traits and the resulting offspring have traits that appear to blend?
incomplete dominance
Each kernel of corn on a single ear can inherit a different set of alleles from those inherited by other kernels. This characteristic makes corn a useful example of which law or principle?
law of independent assortment
Which of Mendel's laws or principles states that gametes carry one allele for each trait?
law of segregation
Which describes the mating of organisms that have different homozygous alleles for a single trait?
monohybrid cross
What controls traits and inheritance?
nucleic acids
Which has the most control of traits and inheritance?
nucleic acids
In the F2 generation of Mendel's crosses,
one in four plants had two alleles for the recessive trait.
Which includes the physical characteristics of an organism?
phenotype
Which type of traits vary quantitatively due to the interaction of multiple genes?
polygenic
Skin color, fur color, and height are examples of which inheritance pattern?
polygenic inheritance
The diagram represents meiosis. mc015-1.jpg Which of Mendel's laws or principles of inheritance can be explained by the diagram?
segregation
The Punnett square predicts the ratio of genotypes in the offspring, based on the genotypes of the parents. In this cross, tallness (H) is dominant to shortness (h). mc016-1.jpg Based on the Punnett square, what is the phenotype of the offspring?
tall
Which type of scientific statement is defined as a hypothesis or group of hypotheses that can be accepted as true based on repeated experimentation with similar results?
theory
What is the purpose of using a pedigree?
to understand patterns of inheritance in organisms
In peas, yellow seed color (Y) is dominant to green seed color (y). Which describes an organism that has nonidentical alleles for seed color?
yy and has green seeds