Bio 160 -Ch. 9 quiz

All the offspring of a cross between a black-eyed Mendelian and an orange-eyed Mendelian have black eyes. What is the expected phenotypic ratio of a cross between two orange-eyed Mendelian? 3 black-eyed:1 orange-eyed 1 black-eyed:3 orange-eyed 1 black-eyed:0 orange-eyed 0 black-eyed:1 orange-eyed

0 black-eyed:1 orange-eyed

Using a six-sided die, what is the probability of rolling either a 5 or a 6? 1/6 + 1/6 = 1/3 1/6 1/6 + 1/6 = 2/3 1/6 × 1/6 = 1/36

1/6 + 1/6 = 1/3

Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's first-born child will be female and that their second-born child will be male? 20% 25% 75% 50%

25%

Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But some cats express the dominant phenotype for polydactyly, which results in the development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes and is recognized by the Guinness Book of World Records as the cat with the most toes. Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The total number of toes on each kitten ranges from 21 to 25. One of Jake and Lucy's kittens mates with another cat that has 18 total toes. What is the probability that one of their offspring would have 18 total toes? 50% 100% 75% 0%

50%

If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of the cross AaBb × AaBb? 1:1:1:1 9:3:3:1 8:4:2:2 16:0:0:0

9:3:3:1

Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But some cats express the dominant phenotype for polydactyly, which results in the development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes and is recognized by the Guinness Book of World Records as the cat with the most toes. Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The total number of toes on each kitten ranges from 21 to 25. Along with having a variable number of toes, some kittens from Jake and Lucy's litter had a white spot on their nose. In fact, out of the 16 kittens, all 10 males had the white spot, but none of the 6 females had the white spot. Jake has a white spot on his nose, but Lucy does not. What can you conclude from this information? The genes for the white spot and for polydactyly are linked. A sex-linked gene that controls the expression of the white spot is found on the Y chromosome. The genes for the white spot and for polydactyly are not linked. A sex-linked gene that controls the expression of the white spot is found on the X chromosome.

A sex-linked gene that controls the expression of the white spot is found on the X chromosome.

In some cats, black coat color (B) is dominant over brown (b) and a striped fur pattern (S) is dominant over a marbled fur pattern (s). You rescued a black striped cat from an animal shelter but could not determine its exact genotype. To do so, you mated the cat with a brown marbled cat. The mating produced 3 brown marbled, 2 brown striped, 2 black marbled, and 3 black striped. Immediately, you concluded the genotype of your rescued cat was BbSS. BBSS. BBSs. BbSs.

BbSs.

Which of the following statements regarding genetic testing is false? Most human genetic diseases are treatable if caught early. The screening of newborns can catch inherited disorders right after birth. Genetic testing before birth requires the collection of fetal cells. Carrier testing helps determine whether a person carries a potentially harmful disorder.

Most human genetic diseases are treatable if caught early.

In giraffes, long necks (N), long legs (L), dark spots (D), and the ability to digest meat (M) are all dominant traits. What possible genotype could a long-necked, short-legged, light-spotted, meat-digesting giraffe have? NNllddmm NNLLDdMm NnllddMM nnLLddMM

NnllddMM

Which of the following statements best represents the theory of pangenesis developed by Hippocrates? Particles called pangenes, which originate in each part of an organism's body, collect in the sperm or eggs and are passed on to the next generation. Heritable traits are influenced by the environment and the behaviors of the parents. Pregnancy is a spontaneous event, and the characteristics of the offspring are determined by the gods. Offspring inherit the traits of either the mother or the father, but not both.

Particles called pangenes, which originate in each part of an organism's body, collect in the sperm or eggs and are passed on to the next generation.

Which of the following statements regarding hypotheses about inheritance is false? The blending hypothesis suggests that all of the traits of the offspring come from either the mother or the father. The theory of pangenesis incorrectly suggests that reproductive cells receive particles from somatic cells. Contrary to the theory of pangenesis, somatic cells do not influence eggs or sperm. The blending hypothesis does not explain how traits that disappear in one generation can reappear in later generations.

The blending hypothesis suggests that all of the traits of the offspring come from either the mother or the father.

You are looking at an unknown cell under a microscope that has 22 chromosomes plus two X chromosomes. Which of the following is the most likely identity of this cell? an epithelial cell from a male chicken an egg from a human female an eye cell from a female grasshopper a skin cell from a human female

an eye cell from a female grasshopper

Research since Mendel's time has established that the law of segregation of genes during gamete formation is invalid. applies to all asexually reproducing organisms. applies to all forms of life. applies to all sexually reproducing organisms.

applies to all sexually reproducing organisms.

For most sexually reproducing organisms, Mendel's laws can predict whether offspring will be male or female with 100% accuracy. explain the biological mechanisms behind why certain genes are dominant or recessive. cannot strictly account for the patterns of inheritance of many traits. help us understand the global geographic patterns of genetic disease.

cannot strictly account for the patterns of inheritance of many traits.

A person with AB blood illustrates the principle of codominance. incomplete dominance. polygenic inheritance. pleiotropy.

codominance.

The expression of both alleles for a trait in a heterozygous individual illustrates incomplete dominance. polygenic inheritance. pleiotropy. codominance.

codominance.

According to this figure, heterozygotes for this form of hypercholesterolemia suffer from the disease because they produce an abnormally shaped LDL receptor. don't produce any LDL receptors. don't produce enough LDL receptors. produce too many LDL receptors.

don't produce enough LDL receptors.

Mendel's law of independent assortment states that genes are sorted concurrently during gamete formation. chromosomes sort independently of each other during mitosis and meiosis. each pair of alleles segregates independently of the other pairs of alleles during gamete formation. independent sorting of genes produces polyploid plants under some circumstances.

each pair of alleles segregates independently of the other pairs of alleles during gamete formation.

A carrier of a genetic disorder who does not show symptoms is most likely to be ________ to transmit it to offspring. heterozygous for the trait and able homozygous for the trait and able heterozygous for the trait and unable homozygous for the trait and unable

heterozygous for the trait and able

Amniocentesis and chorionic villus sampling allow for ________ and ________ of the fetus so that it can be tested for abnormalities. direct observation; biochemical testing sexing; imaging imaging; karyotyping karyotyping; biochemical testing

karyotyping; biochemical testing

Mendel conducted his most memorable experiments on fruit flies. roses. guinea pigs. peas.

peas.

Imagine that we mate two black Labrador dogs with normal vision and find that three of the puppies are like the parents, but one puppy is chocolate with normal vision and another is black with PRA (progressive retinal atrophy, a serious disease of vision). We can conclude that the same alleles that control coat color can also cause PRA. the alleles for color and vision segregate dependently during gamete formation. both of the parents are homozygous for both traits. the alleles for color and vision segregate independently during gamete formation.

the alleles for color and vision segregate independently during gamete formation.