front 1 A child with type AB blood could not be the offspring of a man with type ___ blood. A B AB O | back 1 Answer: B |
front 2 A gene that masks the expression of a second gene is haplosufficient. incompletely dominant. epistatic. homeostatic. | back 2 Answer: C |
front 3 A man with the A blood type marries a woman with blood type B. Which blood type or types could their children have? A B O A, B, AB, or O | back 3 Answer: D |
front 4 People with which of the following blood types can receive a transfusion from a type O donor? type A type B type AB A, B, or AB | back 4 Answer: D |
front 5 For an autosomal gene with three alleles, a diploid cell may have up to how many different alleles of that gene? 0 1 2 3 | back 5 Answer: C |
front 6 A monohybrid cross for a trait with incomplete dominance yielded 200 offspring. ______ of these are expected to exhibit the intermediate phenotype. 50 100 150 All 200 | back 6 Answer: B |
front 7 In a cross involving a genetic locus with an allele for red color and one for white, some of the progeny appear both red and white. This is an example of complete dominance. incomplete dominance. codominance. irregular dominance. | back 7 Answer: C |
front 8 In a particular population carrying a dominant mutant allele, only 70% of the people carrying the allele show the phenotype, and only a small percentage of those showing the phenotype display the most severe symptoms. The gene responsible for this disorder exhibits incomplete penetrance and epistasis. epistasis and variable expressivity. variable expressivity and incomplete penetrance. incomplete penetrance and incomplete dominance. | back 8 Answer: C |
front 9 In certain types of sheep, horns are a trait limited to males, although both male and female sheep carry the genes for horns. This is an example of a ___ trait. sex-linked sex-limited sex-influenced sex-determined | back 9 Answer: B |
front 10 In gremlins, coat color is determined by a gene with multiple alleles. The three alleles involved are: B (brown color); b (white color); and b a (brown and white stripes). For this locus, B is dominant to both b and b a , and b a is dominant to b . In a cross between a B / b a male gremlin and a B / b female gremlin, what percentage of the offspring will have brown and white stripes? 0 25 50 100 | back 10 Answer: B |
front 11 In the M-N blood group system, a heterozygote for the L M and L N alleles will express which antigen on the blood cell surfaces? M only N only both M and N neither M or N | back 11 Answer: C |
front 12 Members of a particular family carry a dominant gene that causes their index and ring fingers to be webbed. Although all of the children carry the dominant allele, only seven of the ten children in this family have the webbed phenotype. This indicates that the gene involved in this phenotype is completely dominant. incompletely dominant. incompletely penetrant. epistatic. | back 12 Answer: C |
front 13 Pattern baldness in men is an example of a ___ trait. sex-linked sex-limited sex-influenced sex-determined | back 13 Answer: C |
front 14 Huntington disease is an example of a dominant lethal allele. a recessive lethal disease. dominant epistasis. recessive epistasis | back 14 Answer: A |
front 15 The expression of the pattern baldness phenotype in men is directly related to their age. nutritional pattern. exposure to dangerous chemicals. level of stress. | back 15 Answer: A |
front 16 The gene for red hair color in Smurfs masks the expression of a
second gene for orange hair. The gene for orange hair is ___ to the
gene for red hair.
epistatic incompletely dominant hypostatic haplosufficient | back 16 Answer: C |
front 17 The genotype of a person with type O blood is ii . I A I A . I A i . I B i . | back 17 Answer: A |
front 18 A dihybrid cross for two kernel color genes in corn yields the phenotypic ratio 9:3:4. What is the most likely explanation for this ratio? incomplete dominance lethal allele epistasis incomplete penetrance | back 18 Answer: C |
front 19 If there are four types of homozygotes for a given gene in a diploid, how many alleles are there for this gene? 1 2 3 4 | back 19 Answer: D |
front 20 An allele mutation that leads to the overproduction of a gene product is expected to express in _____ fashion. recessive codominant incompletely dominant dominant | back 20 Answer: D |
front 21 A cross between two heterozygotes gives a 1:2 genotypic ratio in the offspring. This is probably due to epistasis. a recessive lethal allele. a dominant lethal allele. incomplete dominance. | back 21 Answer: B |
front 22 A cross between a pink flower and a white flower produces 1/2 pink and 1/2 white flowers. A cross between a red flower and a pink flower produces 1/2 red flowers and 1/2 pink flowers. What is this an example of? complete dominance incomplete dominance codominance environmental effects | back 22 Answer: B |
front 23 Five plants of the same genotype are different shades of green. This may be an example of constant expressivity. complete penetrance. variable expressivity incomplete penetrance | back 23 Answer: C |
front 24 When the offspring of a mating all have the same phenotype for a trait as the female parent, this is an example of maternal effect. paternal effect complete dominance codominance | back 24 Answer: A |
front 25 A cross between two true-breeding mutant flies for a given trait leads to all wild-type flies for that trait. This is an example of maternal effect. incomplete dominance. incomplete penetrance complementation | back 25 Answer: D |