31) Drosophila (fruit flies) usually have long wings (+) but : 1828389
31) Drosophila (fruit flies) usually have long wings (+) but mutations in two different genes can result in bent wings (bt) or vestigial wings (vg). If a homozygous bent wing fly is mated with a homozygous vestigial wing fly, which of the following offspring would you expect?
A) All +bt +vg heterozygotes
B) 1/2 bent and 1/2 vestigial flies
C) All homozygous + flies
D) 3/4 bent to 1/4 vestigial ratio
E) 1/2 bent and vestigial to 1/2 normal
32) The flower color trait in radishes is an example of which of the following?
A) A multiple allelic system
B) Sex linkage
D) Incomplete dominance
A) complete dominance.
B) multiple alleles.
C) incomplete dominance.
D) polygenic inheritance.
34) In snapdragons, heterozygotes for one of the genes have pink flowers, whereas homozygotes have red or white flowers. When plants with red flowers are crossed with plants with white flowers, what proportion of the offspring will have pink flowers?
35) Tallness (T) in snapdragons is dominant to dwarfness (t), while red (R) flower color is dominant to white (r). The heterozygous condition results in pink (Rr) flower color. A dwarf, red snapdragon is crossed with a plant homozygous for tallness and white flowers. What are the genotype and phenotype of the F1 individuals?
A) ttRr–dwarf and pink
B) ttrr–dwarf and white
C) TtRr–tall and red
D) TtRr–tall and pink
E) TTRR–tall and red
36) Skin color in a certain species of fish is inherited via a single gene with four different alleles. How many different types of gametes would be possible in this system?
A) red × white
B) roan × roan
C) white × roan
D) red × roan
E) The answer cannot be determined from the information provided.
Refer to the following to answer the questions below.
Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cactuses have dull spines. At the same time, a second gene, N, determines whether cactuses have spines. Homozygous recessive nn cactuses have no spines at all.
38) The relationship between genes S and N is an example of
A) incomplete dominance.
C) complete dominance.
39) A cross between a true-breeding sharp-spined cactus and a spineless cactus would produce
A) all sharp-spined progeny.
B) 50% sharp-spined, 50% dull-spined progeny.
C) 25% sharp-spined, 50% dull-spined, 25% spineless progeny
D) all spineless progeny.
E) It is impossible to determine the phenotypes of the progeny.
40) If doubly heterozygous SsNn cactuses were allowed to self-pollinate, the F2 would segregate in which of the following ratios?
Use the information given here to answer the following questions.
Feather color in budgies is determined by two different genes Y and B, one for pigment on the outside and one for the inside of the feather. YYBB, YyBB, or YYBb is green; yyBB or yyBb is blue; YYbb or Yybb is yellow; and yybb is white.