Mader Biology 14th Edition — Chapter 11 — Multiple Choice and True/False Review

Chapter 11 source question 1. If the probability of event A is 3/4 and the probability of event B is 1/4, then the probability of both A and B occurring at the same time is A) 3/16. B) 1/2. C) 3/4. D) 1/4. E) 1 or absolute certainty.

A) 3/16.

Chapter 11 source question 2. Polygenic traits such as height or weight are often influenced by the environment of the organism. True or False?

TRUE.

Chapter 11 source question 3. When an individual of African descent marries and has children with an individual of European descent, their children often have a mid-shade of skin color, but they could also have a light shade or a dark shade.This can best be described as A) X-linked inheritance. B) polygenic inheritance. C) pleiotropic inheritance. D) the dominance of the gene for dark skin tone.

B) polygenic inheritance.

Chapter 11 source question 4. As many as 60% of people in malaria-infected regions of Africa have the sickle-cell allele, but only about 10% of the U.S. population of African ancestry carries the allele. Malaria remains a major disease in central Africa but has not been a serious problem in the U.S. for many generations. What is/are the reason(s) for the difference in the percentages and what is a reasonable statement about future percentages? A) The presence of malaria in Africa maintains the advantage of the heterozygous sickle-cell trait, and the prevalence of malaria will likely continue to preserve the 60% rate. B) Lack of widespread malaria in the United States would have resulted in both homozygous and heterozygous carriers of sickle cell undergoing several generations of negative selection. We should expect this to continue unless innovative therapies give all individuals an equal chance of surviving and repr

C) All of the choices are reasonable.

Chapter 11 source question 5. Some plants fail to produce chlorophyll, and this trait appears to be recessive. Many plants also self-pollinate. If we locate a pea plant that is heterozygous for this trait, self-pollinate it and harvest seeds, what are the likely phenotypes of these seeds when they germinate? A) About one-half will be green and one-half white. B) About one-fourth will be green and three-fourths white. C) All will be white and lack chlorophyll. D) About one-fourth will be white and three-fourths green. E) All will be green with chlorophyll.

D) About one-fourth will be white and three-fourths green.

Chapter 11 source question 7. When crossing a true-breeding red snapdragon flower with a true-breeding white flower of the same species, all offspring are pink. This would seem to support the pre-Mendel view that inheritance is a blending of parental traits. However, Mendel and conventional wisdom agree that "blending" of parental traits is not correct and that particles of inheritance are actually involved. Which of the following statements supports the idea of particulate inheritance? A) Over many generations of crossing individuals with the incompletely dominant phenotype, all the progeny are pink. B) Two parents that show the incompletely dominant phenotype produce some offspring that are red and some that are white. C) There is no way to directly prove that incomplete dominance is not a case of blending. D) In meiosis, alleles of different genes assort independently of each other during gamete formation.

B) Two parents that show the incompletely dominant phenotype produce some offspring that are red and some that are white.; D) In meiosis, alleles of different genes assort independently of each other during gamete formation.

Chapter 11 source question 8. Computer simulations are sometimes used to demonstrate the outcome of monohybrid fruit fly crosses, where a student can run generation after generation of fruit flies with 100 offspring produced each generation, half male and half female, and a 3-to-1 phenotype ratio (or 75 to 25) in the F 1 generation. Compared with real genetics results, A) rarely would exactly 100 fly offspring be produced or survive. B) All of the choices are true. C) a precise 3-to-1 ratio would be uncommon. D) an exact balance between males and females would be rare.

B) All of the choices are true.

Chapter 11 source question 9. If individuals exhibiting a dominant phenotype are crossed and produce only offspring with the dominant phenotype, which of the following could be the genotype of the parents? A) One is heterozygous and one is homozygous dominant. B) Both are heterozygous. C) Both are homozygous dominant. D) Two of the options may be correct. E) Both are homozygous recessive.

D) Two of the options may be correct.

Chapter 11 source question 10. The reason why some individuals who inherit polydactyly (having an extra digit on the hand or feet) do not express the trait is due to A) pleiotropy. B) incomplete dominance. C) None of the answers are correct. D) gene linkage. E) incomplete penetrance.

E) incomplete penetrance.

Chapter 11 source question 11. Women with an X-linked disorder could pass the genes for the disorder to _____, and men with an X-linked disorder could pass the genes for the disorder to _____. A) both their daughters and sons; their daughters and sons B) both their daughters and sons; only their sons C) only their daughters; only their daughters D) both their daughters and sons; only their daughters

D) both their daughters and sons; only their daughters.

Chapter 11 source question 12. Which allele combination represents a homozygous dominant individual? A) Aa B) None of these are homozygous dominant individuals. C) aa D) AA

D) AA.

Chapter 11 source question 13. In 1940, two researchers named Weiner and Landsteiner discovered that about 85 percent of the human population sampled possessed a blood cell protein that had been previously detected in Rhesus monkeys. This blood type was labeled Rh positive, and Rh + was found to be dominant over the absence of the blood factor (Rh -). Under normal Mendelian inheritance, which of the following statements is FALSE? A) Two Rh - parents could have an Rh + child. B) Two Rh + parents could have an Rh - child. C) An Rh - child would require that both parents be carriers of at least one Rh - gene. D) It is possible with just one pair of parents to have children where some siblings are Rh and some are Rh +. - E) All of the choices are false.

A) Two Rh - parents could have an Rh + child.

Chapter 11 source question 14. Which of the following is not part of Mendel's law of segregation? A) Each gamete will carry two factors for a trait. B) The factors segregate during meiosis. C) Each individualhas two factors for each trait. D) Fertilizationgives the offspring two factors for each trait.

A) Each gamete will carry two factors for a trait.

Chapter 11 source question 15. Upon examination, a person is found to only have half the normal number of LDL- cholesterol receptors. Which of the following best explains this? A) incompletedominance B) X-linkedinheritance C) polygenicinheritance D) pleiotropicinheritance

A) incompletedominance.

Chapter 11 source question 17. If an individual with a dominant phenotype is crossed with an individual with a recessive phenotype, 4 of their 9 offspring show the recessive phenotype. What is the genotype of the first parent? A) Aa B) AA C) aa D) The answer cannot be determined from this information.

A) Aa.

Chapter 11 source question 18. What is pleiotropy? A) A single mutant gene affects one trait. B) A single mutant gene has no affect on an individual's phenotype. C) A single mutant gene affects two or more distinct and seemingly unrelated traits. D) Two mutant genes affect one trait.

C) A single mutant gene affects two or more distinct and seemingly unrelated traits.

Chapter 11 source question 21. In what kind of classic Mendelian cross would you expect to find a ratio of 9:3:3:1 among the F 2 offspring? A) None of the choices are correct. B) monohybrid cross C) testcross D) dihybrid cross

D) dihybrid cross.

Chapter 11 source question 22. What is the blending theory of inheritance? A) A theory that describes how offspring show traits intermediate between those of the parents. B) Mendel's theory of how traits are passed from parent to offspring. C) The modern theory of how genetic information is passed from parents to offspring. D) Darwin's theory of how traits are passed from the parent to the offspring.

A) A theory that describes how offspring show traits intermediate between those of the parents.

Chapter 11 source question 23. The offspring of a monohybrid testcross could have what possible genotype(s)? A) AA only B) AA, Aa, and aa C) Aa and aa D) aa only E) AA and Aa

C) Aa and aa.

Chapter 11 source question 24. The most common lethal genetic disease among Caucasians is A) Tay-Sachs disease. B) albinism. C) cystic fibrosis. D) neurofibromatosis. E) phenylketonuria.

C) cystic fibrosis.

Chapter 11 source question 25. Since each child of two heterozygous parents has a 50% chance of receiving a recessive trait from each parent, A) if the first child is phenotypically recessive, then the next child has a 3/4 chance of being phenotypically recessive. B) no matter what the first child's phenotype, the next child will have a 1/4 chance of being phenotypically recessive. C) if the first child is phenotypically recessive, then the next child must be phenotypically dominant. D) if the first child is phenotypically recessive, then the next child has a 1/2 chance of being phenotypically recessive.

B) no matter what the first child's phenotype, the next child will have a 1/4 chance of being phenotypically recessive.

Chapter 11 source question 26. During Mendel's pea plants experiment, he discovered that the trait for tallness is dominant to that of shortness. Which of the following statements is correct? A) Tall = tt whileshort = TT or Tt B) None of thesestatements are correct. C) Tall = TT or Ttwhile short = tt D) Tall = TT or ttwhile short = Tt

C) Tall = TT or Ttwhile short = tt.

Chapter 11 source question 27. Which of the following disorders is not a X-linked trait? A) All of these are X-linked disorders. B) muscular dystrophy C) hemophilia D) adrenoleukodystrophy

A) All of these are X-linked disorders.

Chapter 11 source question 28. In pea plants, the gene for round seeds (R) is dominant, and wrinkled seeds (r) is recessive. The endosperm of the pea is also either starchy, a dominant gene (S), or waxy (s). What can be said of a fully heterozygous, dihybrid cross? A) All of these choices are possible combinations in a dihybrid cross. B) Some offspring could be homozygous for both recessive genes. C) All of these choices are impossible combinations in a dihybrid cross. D) Some offspring could be homozygous for both dominant genes. E) Some offspring could be homozygous for one dominant gene such as round seed and homozygous recessive for the other recessive waxy gene.

A) All of these choices are possible combinations in a dihybrid cross.

Chapter 11 source question 29. Which is associated with the inability to produce factor VIII in the blood? A) hemophilia A B) trisomy 21 C) Duchenne muscular dystrophy D) Williams syndrome E) color blindness

A) hemophilia A.

Chapter 11 source question 30. Which of the following statements accurately describes Gregor Mendel? A) He was very deliberate and followed the scientific method closely while doing his research. B) All of the statements accurately describe Gregor Mendel. C) He conducted many preliminary studies with various animals and plants. D) He had a strong background in mathematics. E) He kept very detailed records of his research.

B) All of the statements accurately describe Gregor Mendel.

Chapter 11 source question 31. In a case of incomplete dominance, the phenotypic ratio of the F 2 generation is the same as the genotypic ratio. True or False?

TRUE.

Chapter 11 source question 32. If a woman is a carrier for the color blind recessive allele and her husband is normal, what are their chances that their son will be color blind? A) None since he will be a carrier like his mother. B) 100% because the mother is a carrier. C) 50% since the mother is a carrier. D) None since the father is normal.

C) 50% since the mother is a carrier.

Chapter 11 source question 33. Haiti is settled by peoples of both African and European ancestry. A young couple, both with mixed ancestry, marry and have several children. The children, who all have equal exposure to sunlight, vary widely in the amount of skin melanin. One child is lighter than both parents, and one is darker. The simple explanation for this is A) epistasis. B) multiple alleles are available for the one chromosomal locus that governs skin color. C) polygenic inheritance. D) gene linkage. E) the environment influenced the phenotypes of the children.

C) polygenic inheritance.

Chapter 11 source question 34. If an individual is heterozygous for a particular trait, the gametes that individual produces will contain 3/4 dominant and 1/4 recessive alleles. True or False?

FALSE.

Chapter 11 source question 35. Which allele combination represents a heterozygous individual? A) None of these represent a heterozygous individual. B) AA C) aa D) Aa

D) Aa.

Chapter 11 source question 36. A single, simple, recessively inherited mutation inactivates the enzyme that converts phenylalanine to tyrosine. Homozygous recessive individuals possess an excessive amount of phenylalanine and a deficiency of tyrosine. Additionally, these individuals may be mentally deficient, have abnormally light hair and abnormally light skin color. This disorder is an example of A) pleiotropy. B) polygenic inheritance. C) incomplete dominance. D) incomplete penetrance.

A) pleiotropy.

Chapter 11 source question 37. Which of the following statements is NOT true according to Mendel's law of segregation? A) One factor must be dominant and one factor recessive in each individual. B) Fertilization restores the presence of two factors. C) Each individual contains two factors for each trait. D) Factors separate from each other during gamete formation. E) Each gamete contains one copy of each factor.

A) One factor must be dominant and one factor recessive in each individual.

Chapter 11 source question 38. A testcross involves an individual with the dominant phenotype but unknown genotype being crossed with an individual that has a(n) ________ genotype. A) heterozygous dominant B) homozygous dominant C) homozygous recessive D) Any of the choices.

C) homozygous recessive.

Chapter 11 source question 39. If black fur is produced by a recessive allele, which genotype is most likely to produce a black individual? A) BB B) bb C) Cb D) Bb

B) bb.

Chapter 11 source question 40. Which of the following is NOT a trait that is the result of, or is affected by, the interaction of more than one gene? A) cleft palate B) human skin color C) sickle-cell anemia D) height

C) sickle-cell anemia.

Chapter 11 source question 41. The ability to roll the edges of the tongue upward in a U-shape is considered to be an inherited trait. The standard assumption is that tongue-rolling is a dominant allele at a single gene locus. Which of the following would cast doubt on this assumption? Select all that apply. A) A student who can roll his tongue has both a mother and father who cannot. B) A student who cannot roll his tongue has both a mother and father who can. C) A research study with 1,000 participants reports that most non-tongue-rollers can learn to roll their tongues. D) In a large research study, the majority of tongue-rollers were male. A B

A) A student who can roll his tongue has both a mother and father who cannot.; C) A research study with 1,000 participants reports that most non-tongue-rollers can learn to roll their tongues.; D) In a large research study, the majority of tongue-rollers were male. A B

Chapter 11 source question 42. If two parents have blood genotypes I i and I i, which of the following blood genotypes are possible in their children? A) I AI A, I BI B, and I AI B only B) I Ai, I Bi, and I AI B only C) I Ai and I Bi only D) I Ai, I Bi, I AI B and ii E) I Ai, I Bi, and ii only

D) I Ai, I Bi, I AI B and ii.

Chapter 11 source question 43. Which statement about the blending concept of inheritance is correct? A) A cross between atall man and a short woman would always produce children of medium height. B) A cross between atall man and a short woman can produce some children that are tall while othersare short. C) Genetic material isunstable which accounts for such a wide diversity in our offspring. D) A cross between a tall man and a short woman produces tall children who can then produce short grandchildren.

A) A cross between atall man and a short woman would always produce children of medium height.

Chapter 11 source question 44. The particulate theory of inheritance A) All of the choices are correct. B) is based on particles or hereditary units we now call genes. C) Two of the above choices are correct. D) preceded Mendel's research by a century. E) was proposed by Mendel.

C) Two of the above choices are correct.

Chapter 11 source question 45. If a human who is a tongue roller (T) and has unattached ear lobes (E) marries a person who cannot roll their tongue and has attached earlobes, could they produce an offspring that was also a non-tongue-roller with attached earlobes? What would be the genotype of the first parent? The second parent? A) unable to determine from the information given B) yes; TtEE; ttEe C) yes; TtEe; ttee D) no; TTEE; ttee

C) yes; TtEe; ttee.

Chapter 11 source question 46. The F 2 offspring of a classic Mendelian monohybrid cross between homozygous dominant and homozygous recessive parents would produce the genotype(s) A) Aa only. B) AA and Aa. C) Aa and aa. D) AA only. E) AA, Aa, and aa.

E) AA, Aa, and aa.

Chapter 11 source question 47. Unattached earlobes (EE or Ee) are described in the textbook as dominant over attached earlobes (ee). A couple both have unattached earlobes. Both notice that one of their parents on both sides has attached earlobes (ee). Therefore, they correctly assume that they are carriers for attached earlobes (Ee). The couple proceeds to have four children. A) Two heterozygous, one homozygous recessive, and one homozygous dominant is a likely outcome, but all heterozygous, or two, three, or all four homozygous are also possible. B) They can be certain that three will be heterozygous and one homozygous recessive. C) If the first three are heterozygous, the fourth must be homozygous recessive. D) All children must have unattached earlobes since both parents possess the dominant gene for it. E) The children must repeat the grandparents' genotype (Ee).

A) Two heterozygous, one homozygous recessive, and one homozygous dominant is a likely outcome, but all heterozygous, or two, three, or all four homozygous are also possible.

Chapter 11 source question 48. If a pea plant shows a recessive phenotype, A) the genotype may be Tt or tt. B) the genotype can only be tt. C) the genotype may be TT or Tt. D) the genotype can only be TT. E) the genotype may be TT, Tt, or tt.

B) the genotype can only be tt.

Chapter 11 source question 50. In a Punnett square, A) all the possible types of eggs are lined up either horizontally or vertically. B) the results show the offspring's expected genotypes. C) Only two of thechoices are correct. D) All of the choicesare correct. E) all the possible types of sperm are lined up either horizontally or vertically.

D) All of the choicesare correct.

Chapter 11 source question 51. In a classic Mendelian monohybrid cross between a homozygous dominant parent and a homozygous recessive parent, which generation is always completely heterozygous? A) F 2 generation B) F 3 generation C) F 1 generation D) P generation

C) F 1 generation.

Chapter 11 source question 52. Lethal genes (genes that result in the failure to develop a vital organ or metabolic pathway) are nearly always recessive. Animal breeders who discover a unique trait and selectively breed to increase the occurrence of that trait often encounter a noticeable increase in lethal genes. Why? A) "Epistasis"—selection for the desired trait may result in "uncovering" the lethal gene. B) The lethal recessive gene may be incompletely dominant. C) "Pleiotropy"—the gene that is being selected for this trait may have the second effect of being lethal. D) The selective-mating of closely related individuals, or inbreeding, increases the chances that two recessive genes will "meet" in offspring. E) Spreading the gene among offspring of both sexes will increase the likelihood it will be sex-linked and expressed.

D) The selective-mating of closely related individuals, or inbreeding, increases the chances that two recessive genes will "meet" in offspring.

Chapter 11 source question 53. Cystic fibrosis and phenylketonuria are common autosomal dominant disorders. True or False?

FALSE.

Chapter 11 source question 54. If white eyes are produced by a recessive allele, what is the likely genotype of a white- eyed individual? A) Rr B) RR C) RB D) rr

D) rr.

Chapter 11 source question 56. Which of the following crosses will NOT produce offspring with the recessive phenotype? Select all that apply. A) TT x Tt B) Tt x Tt C) TT x TT D) Tt x tt E) tt x tt

A) TT x Tt; C) TT x TT.

Chapter 11 source question 57. Why did Mendel choose pea plants for his research? A) Pea plants have a short generation time. B) Peas are easy to cultivate. C) Many true-breeding varieties were available. D) Pea plants are self-pollinating but can be cross-fertilized easily. E) All of these were important characteristics in Mendel's selection.

E) All of these were important characteristics in Mendel's selection.

Chapter 11 source question 58. Each gamete carries one factor, now called an allele, for each inherited trait. True or False?

TRUE.

Chapter 11 source question 59. What aspect of Mendel's background gave him the necessary tools to discover the laws of inheritance? A) He lived in Austria. B) He had studied mathematics and probability. C) He was a monk. D) He corresponded with Charles Darwin. E) He was a teacher.

B) He had studied mathematics and probability.