bio test 3 ch. 23 questions

14. In guinea pigs, B = black, b = brown, S = short hair, s = long hair. A heterozygous black, short-haired animal reproduces with a brown, long-haired animal. What is the expected phenotypic ratio of the offspring? A. 1 black short hair, 1 black long hair, 1 brown short hair, 1 brown long hair B. 9 black short hair, 3 black long hair, 3 brown long hair, 1 brown short hair C. 9 black short hair, 3 black long hair, 3 brown short hair, 1 brown long hair D. 9 black short hair, 6 black long hair, 3 brown long hair, 1 brown short hair

A. 1 black short hair, 1 black long hair, 1 brown short hair, 1 brown long hair

15. In humans, aniridia, a type of blindness, is due to a dominant allele A. Migraine headaches are due to another dominant allele M. If a man who suffers from both conditions (AaMm) marries a woman who suffers from both (AaMm), what are the chances of an offspring expressing both traits. A. 9/16 B. 3/16 C. 1/2 D. 1/16

A. 9/16

What type of inheritance is represented by the above pedigree? Remember, affected individuals are represented by filled in shapes. A. Autosomal Dominant B. Autosomal Recessive

A. Autosomal Dominant

8. In a Mendelian monohybrid cross involving two homozygous genotypes, the ____ generation is always completely heterozygous. A. F1 B. F2 C. P D. P2

A. F1

Common fruit flies, Drosophila melanogaster, have been used as model organisms to study inheritance in animals for many years. Flies with the yellow body phenotype make no melanin. Look at the image above to see diagrams representing the "wild-type" and "yellow body" flies. In an experiment, Karen crossed a true-breeding line of wild-type flies with yellow body flies. All the offspring of those crosses were wild-type. Then Karen crossed the offspring with each other. She got 328 yellow body flies and 1014 wild-type flies. What is the probably inheritance pattern for the yellow body allele? A. Yellow body is recessive to wild-type. B. Wild-type is recessive to yellow body. C. Wild-type and yellow body are incompletely dominant. D. Wild-type and yellow body are codominant.

A. Yellow body is recessive to wild-type.

29. In peas, yellow is dominant over green in seeds. With which of these is it best to cross a yellow-seeded pea plant to determine whether it is homozygous or heterozygous? A. a green-seeded plant B. a heterozygous yellow-seeded plant C. a pure yellow-seeded plant D. a heterozygous yellow-seeded plant or a pure yellow-seeded plant

A. a green-seeded plant

1. Alternative forms of a gene that influence the same trait and are found at the same location in homologous chromosomes are called A. alleles. B. phenotypes. C. genotypes. D. incomplete dominance.

A. alleles

7. Mendel's law of segregation implies that the two members of an allele pair A. are distributed to separate gametes. B. are distributed to the same gamete. C. are assorted dependently. D. are segregated pairwise.

A. are distributed to separate gametes.

26. You have two true-breeding rose bushes, one with red flowers and one with white flowers. A cross between these two roses yields a bush with white flowers that have red splotches. What condition does this demonstrate? A. codominance B. incomplete dominance C. environmental effects D. polygenetic inheritance E. monohybrid inheritance

A. codominance

2. Which of the following represents the physical characteristics of the individual? A. phenotype B. genotype C. alleles D. dominance

A. phenotype

18. What genetic disorder is associated with the lack of an enzyme necessary for the normal metabolism of the amino acid phenylalanine? A. phenylketonuria (PKU) B. Huntington disease C. sickle cell disease D. cystic fibrosis (CF)

A. phenylketonuria (PKU)

22. Traits that are controlled by several sets or pairs of alleles, such as skin color and height in humans, are the result of what form of inheritance? A. polygenic B. incomplete dominance C. simple Mendelian inheritance D. codominance

A. polygenic

19. Which genetic disorder is associated with an irregular shape of the red blood cells? A. sickle cell disease B. Marfan syndrome C. Huntington disease D. cystic fibrosis (CF)

A. sickle cell disease

20. What are the chances that two individuals with wavy hair (an incomplete trait) will have a curly-haired child? Curly hair and straight hair exhibit incomplete dominance. A. none B. 25% C. 50% D. 75%

B. 25%

6. Which is NOT true according to Mendel's law of segregation? A. Each individual contains two alleles for each trait. B. An individual can have either both dominant alleles, both recessive alleles, or a dominant and recessive allele. C. Alleles separate from each other during gamete formation. D. Each gamete contains one copy of each allele. E. Fertilization restores the presence of two alleles.

B. An individual can have either both dominant alleles, both recessive alleles, or a dominant and recessive allele.

34. A man with AB blood type can have a child with type O. A. True B. False

B. False

3. What are alleles? A. genes for different traits, such as hair color and eye color B. alternative forms of a gene for a single trait, such as blue eyes or brown eyes C. the locations of genes on a chromosome D. recessive forms of a kind of characteristic carried by genes

B. alternative forms of a gene for a single trait, such as blue eyes or brown eyes

24. You have two true-breeding rose bushes, one with red flowers and one with white flowers. A cross between these two roses yields a bush with pink flowers. What condition does this demonstrate? A. codominance B. incomplete dominance C. environmental effects D. polygenetic inheritance

B. incomplete dominance

27. Cold weather can change the ______ of a Himalayan rabbit. A. genotype B. phenotype C. alleles D. sex

B. phenotype

13. A cross is made between two parents with genotypes AaBB and aabb. If there are 32 offspring, how many of them would be expected to exhibit both dominant characteristics? A. 32 B. 24 C. 16 D. 8 E. 0

C. 16

9. What will the genotypic ratio be of a monohybrid cross of two individuals who are both heterozygous for a trait? Use the link in the instructions to an online Punnet square frame. A. 100% homozygous dominant B. 50% homozygous dominant, 50% homozygous recessive C. 25% homozygous dominant, 50% heterozygous, 25% homozygous recessive D. 50% homozygous dominant, 50% heterozygous

C. 25% homozygous dominant, 50% heterozygous, 25% homozygous recessive

21. The four o'clock flower is an example of incomplete dominance: R = red, r = white, and Rr = pink. If two hybrids are crossed, what are the chances that an offspring will have pink flowers? A. 0% B. 25% C. 50% D. 75% E. 100%

C. 50%

17. In guinea pigs, B = black, b = brown, S = short hair, s = long hair. Two heterozygous individuals reproduce. The expected results are A. 9 black long hair, 3 black short hair, 3 brown long hair, 1 brown short hair. B. 9 black short hair, 6 black long hair, 3 brown long hair, 1 black short hair. C. 9 black short hair, 3 black long hair, 3 brown short hair, 1 brown long hair. D. 9 brown short hair, 3 black long hair, 3 brown long hair, 1 black short hair.

C. 9 black short hair, 3 black long hair, 3 brown short hair, 1 brown long hair.

10. A pheasant breeder starts with two birds in the P generation, one of which is AA and the other is aa. If he takes two of the birds from the F1 generation and breeds them together, what can he expect in his F2 offspring? A. AA and Aa. B. Aa and aa. C. AA, Aa, and aa. D. Aa only.

C. AA, Aa, and aa

12. Some plants fail to produce chlorophyll, due to a recessive trait. If we locate a pea plant that is heterozygous for this trait, self-pollinate it, and harvest the seeds, what are the likely phenotypes of the resulting offspring? A. All will be green with chlorophyll since that is the dominant trait. B. About one-half will be green and one-half white since that is the distribution of the genes in the parents. C. About one-fourth will be white and three-fourths green since it is similar to a monohybrid cross. D. About one-fourth will be green and three-fourths white since it is similar to a monohybrid cross.

C. About one-fourth will be white and three-fourths green since it is similar to a monohybrid cross.

This pedigree documents an autosomal recessive trait. Remember, affected individuals are represented by filled in shapes. What is the genotype of individual 6 at generation II? A. Homozygous Dominant B. Homozygous Recessive C. Heterozygous D. There is not enough information given to tell.

C. Heterozygous

28. Hydrangeas are a flowering plant with large showy blooms. When a plant is grown in aluminum-rich soil it has blue flowers. If the same plant is transplanted into soil that is lacking aluminum, the flowers produced will be pink. This is an example of A. codominance. B. incomplete dominance. C. environmental effects. D. polygenetic inheritance.

C. environmental effects.

4. The _____ indicates the gene combination of an individual. A. phenotype B. loci C. genotype D. homozygous

C. genotype

30. In a testcross, an organism with a dominant phenotype, but unknown genotype is crossed with which of the following to establish its genotype? A. homozygous dominant B. heterozygous C. homozygous recessive D. heterozygous dominant

C. homozygous recessive

5. Which of the following is NOT correct concerning the law of independent assortment? A. It is based upon the process of meiosis. B. Each pair of factors separates independently. C. All possible combinations of factors can occur in the gametes. D. It follows the observation that all maternal chromosomes end up in the egg.

D. It follows the observation that all maternal chromosomes end up in the egg.

23. Which of the following is an example of the blending of phenotypes? A. codominance B. polygenic inheritance C. simple Mendelian inheritance D. incomplete dominance

D. incomplete dominance

25. When two or more genes with multiple alleles affect the same trait in an additive fashion, it is termed A. a double-trait cross. B. codominant. C. incomplete dominance. D. polygenic inheritance.

D. polygenic inheritance

16. In which kind of cross could you expect to find ratios of 1:1:1:1 among the offspring? A. monohybrid cross B. dihybrid cross C. one-trait test cross D. two-trait test cross

D. two-trait test cross

11. A woman who can roll her tongue (presumably dominant) is married to a man who cannot. Two of their four children can roll their tongues and two cannot. If A = roll tongue and a = cannot roll tongue, then what is the genotype of the parents? A. woman Aa; man Aa B. woman AA; man aa C. woman Aa; man AA D. woman Aa; man aa

D. woman Aa; man aa