In the case of complete dominance, if a plant has a ____ genotype for a particular trait, its phenotype will have the ____ trait. | heterozygous; dominant |
Human skin color is an example of ____, while sickle-cell anemia is an example of ____ | polygenic inheritance; pleiotropy |
A parent has a genotype of RrYy. What is the probability of this individual producing a gamete with the RY genotype? | 1/4 |
Wrinkled vs. Round Peas | Dominance |
Human AB Blood Type | Codominance |
Snapdragon Flower color (red, pink, and white) | Incomplete dominance |
Human Height | Polygenic Inheritance |
Labrador Retriever fur color (black, chocolate brown, yellow) | Epistasis |
Using the sum rule, what is the probability of getting one head and one tail (in either order) in two tosses of a coin? | 1/2 |
Your mother has albinism, which is a recessive trait. Your father has cystic fibrosis, which is also a recessive trait. You discover that your new father-in-law has albinism and cystic fibrosis. If neither you nor your spouse has either albinism or cystic fibrosis, what are the odds that your first child will have both albinism and cystic fibrosis? | 1/16 |
Rice plants may be tolerant or intolerant to flooding. A true-breeding tolerant plant was crossed with a true-breeding intolerant plant, and approximately 75% of the F1 generation was tolerant to flooding. What does this most likely suggest about the flood-tolerant and flood-intolerant alleles? | The allele for flood-tolerance is dominant, while the allele for flood-intolerance is recessive. |
Events X and Y are independent of each other. If the probability of event X occurring is 1 in 4, and the probability of event Y occurring is 1 in 5, the probability of both events occurring is ____ | (1/4)(1/5) = 1/20 |
From his experiments, Mendel concluded that each individual carries two factors, or ____, that govern the inheritance of each trait. Different versions of each factor are known as ____ | genes; alleles |
In snapdragons, the red allele CR is incompletely dominant over the white allele CW. Which two plants would you cross to produce a true-breeding pink snapdragon? | a true-breeding pink snapdragon cannot be created |
In snapdragons, the red allele CR is incompletely dominant over the white allele CW. If you cross a pink snapdragon (CRCW) with a white snapdragon (CWCW), what percentage of the progeny will be red? | 0% |
Mouse pigmentation is subject to epistasis of the B alleles by the d alleles. B (black) is dominant over b (brown), and D is dominant over d. Homozygous d is epistatic to the black and brown genes. Given this information, what genotype(s) result in a white mouse (no pigment)? | BBdd and Bbdd |
The different alleles in human blood type are a demonstration of ____ | dominance and codominance |
Characters that have a continuous distribution, such as height, weight, and skin color, are called ____, and the individual genes that control them are known as ____ | quantitative traits; quantitative trait loci |
In pea plants, yellow seed color is dominant to green, and wrinkled seed texture is dominant to smooth. In a dihybrid cross between two heterozygous plants with yellow, round seeds, if the two alleles assort independently, what is/are the predicted phenotypic ratio(s) of the offspring? | 9 yellow and round: 3 green and round: 3 yellow and wrinkled: 1 green and wrinkled |
If your mother and father both have cystic fibrosis, which is caused by a recessive allele, the odds of you having cystic fibrosis are ____ | 1 |
According to the product rule of probability, when two or more events are _____, the probability that they will occur in succession is calculated by _____ the individual probabilities. | independent; multiplying |
Mouse pigmentation is subject to epistasis of the B alleles by the d alleles. B (black) is dominant over b (brown), and D is dominant over d. Homozygous d is epistatic to the black and brown genes. Given this information, what will result from a F1 cross between two mice? | 9/16 black, 3/16 brown, 4/16 white |
A woman with normal blood clotting mates with a man who has hemophilia. Their first child is a boy who has hemophilia. Tests show that the father and son both have the same form of hemophilia, that it is X-linked, and that the boy has normal genetic inheritance. You can predict that if the couple has more children together, it is likely that ____ | half of the boys and half of the girls will have hemophilia |
Mendel crossed true-breeding plants having yellow peas with true-breeding plants having green peas. The resulting plants all had yellow peas. An F1 cross resulted in 3/4 of the plants having yellow peas and 1/4 of the plants having green peas. What does this tell you about the alleles for color? | Yellow is the dominant color. |
Your father is heterozygous for the recessive disorder phenylketonuria (PKU). You know your mother has two "good" alleles. You have a ____chance of having the disorder. | 0% |
In Drosophila melanogaster, the gene for eye color is located on the X chromosome. The allele for red eye color (Xw+) is dominant over the allele for white eye color (Xw). You examine a vial of 100 flies that are all offspring from a single genetic cross. You find both red-eyed females and white-eyed females as well as both red-eyed males and white-eyed males. The genotypes of the parents were ____ | Xw+ Xw; Xw Y |
If a woman has blood type O and a man has blood type AB, what is the probability that they will have a child with blood type O? | 0 |
A couple are both heterozygous for the dominant allele for polydactyly. They want to have three children. What is the probability that all three children will have polydactyly? | 27/64 |
Which notation represents a testcross? (A “dash” indicates the allele's identity is unknown.) | R-M- × rrmm |
The ability of an individual heterozygous for two different genes to produce the four possible gamete types in equal numbers reflects Mendel’s Law(s) of ____ | Segregation and Independent Assortment |
A testcross is used to ____ | determine if a parent with a dominant trait is heterozygous or homozygous |
Examine the pedigree in the figure above. Individuals affected by the genetic condition in question are indicated by filled squares or circles. Which inheritance pattern is most likely correct for this condition in this family? | X-linked dominant |
You are a genetic counselor, and a couple comes to you with concerns that if they have a child together, he or she could have hemophilia. Neither of them has hemophilia, but the woman's biological father did have an X-linked recessive form of hemophilia. How should you advise them? | Each of their sons will have a 50% chance of having hemophilia, and each of their daughters will have a 50% chance of being carriers. |
Incomplete Dominance | When one allele cannot completely mask the effects of another allele |
Genotype | The genetic makeup of an organism |
F1 Generation | The first generation of offspring from the cross of two true-breeding parents |
Heterozygote | Any organism with 2 different alleles of a gene |
P Generation | True-breeding plants used in an initial cross |
Dominance | When one allele masks the effect of another |
Recessive | The allele that is expressed only if two identical copies are present |
Pleiotropy | When a single allele has multiple phenotypic effects |
Epistasis | When alleles at one locus mask the expression of alleles at a different locus |
Polygenic inheritance | When different genes contribute to a particular phenotype |
True breeding | When displayed traits are unchanged over multiple generations |
Monohybrid | An F1 heterozygote (for a single trait) |
F2 generation | The result of a cross between two first-generation organisms |
Homozygote | Any organism with 2 identical alleles of a gene |
Probability | The likelihood of something occurring as a matter of chance |
Phenotype | The physical traits of an organism |
Locus | Where an allele is found on a chromosome |