3. In mice, black fur (B) is dominant to white (b). At a different locus, a dominant allele (A) produces a band of yellow just below the tip of each hair in mice with black fur. This gives a frosted appearance known as agouti. Expression of the recessive allele (a) results in a solid coat color. If mice that are heterozygous at both loci are crossed what is the expected phenotypic ratio of their offspring?

3. In mice, black fur (B) is dominant to white (b). At a different locus, a dominant allele (A) produces a band of yellow just below the tip of each hair in mice with black fur. This gives a frosted appearance known as agouti. Expression of the recessive allele (a) results in a solid coat color. If mice that are heterozygous at both loci are crossed what is the expected phenotypic ratio of their offspring?

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

See similar textbooks

Similar questions

. Miniature wings (X") in Drosophila result from an X-linked allele that is recessive to the allele for long wings (X *). Give the genotypes of the parents in each of the following crosses. Male Female Male offspring Female offspring parent parent 231 long, 250 a. long long 560 long miniature 250 miniature b. miniature long 610 long 632 long 410 long, 417 miniature 412 long, 415 c. miniature long miniature 417 miniature 415 miniature d. long 761 long 630 long miniature 753 miniature e. long long 625 long
Fruit flies with the genotypes XghXgh and Xg+h+Y are crossed. Note that two X-linked loci are being evaluated, and the presence of a + indicates a dominant allele. The heterogametic offspring will... 1.all express a dominant g phenotype and recessive h phenotype. 2. all express both dominant phenotypes. 3. all express both recessive phenotypes. 4. all express a recessive g phenotype and a dominant h phenotype.
3) In the snail Capaea nemoralis, an autosomal allele causing a banded shell (B®) is recessive to the allele for an unbanded shell (B°). Genes at a different locus determine the background color of the shell; here yellow (C') is recessive to brown (CBw). A banded, yellow snail is crossed with a homozygous brown, unbanded snail. The F1 are then crossed with banded, yellow snails (a test cross). a. What will the results of the testcross be in the loci that control banding and color ARE linked with NO crossing over.
2. Brown eyes are dominant over blue eyes in humans. Having a peaked hairline is dominant over having a smooth hairline in humans. Two such humans decide to have offspring – who will also be human, because you know – genes. One of the parents has blue eyes and is heterozygous for a peaked hairline. The other parent is brown-eyed with a peaked hairline but is heterozygous for both traits. a) Complete a Punnett square showing all possible genotypes of their offspring. b) What is the probability of this couple producing a child with blue eyes? c) What is the probability of producing a child who has both brown eyes and a smooth hairline?
1. Two loci found in mice are suspected to be linked. To test this hypothesis, a group of graduate students performed a test cross between mice that are true breeding for both dominant traits and mice that are true breeding for both recessive traits. Individuals from the F1 generation were crossed with individuals that express both recessive traits. The phenotypic results are shown in the table below. Use chi-square analysis to determine if the graduate students’ hypothesis is supported by the evidence. Phenotype Number of OffspringDominant 1, Recessive 2 132Dominant 1, Dominant 2 128Recessive 1, Recessive 2 118Recessive 1, Dominant 2 124 a. What are the degrees of freedom and the critical chi-square value (from the table)?b. What is the calculated chi-square value?c. Do the results support that the loci are linked or that they are independently assorted (unlinked)?
8. In guinea pigs, the allele for black fur (B) is dominant over the allele for white fur (b). Similarly, the allele for straight hair (H) is dominant over the allele for having rough hair (h). Pure breeding rough haired guinea pigs with black fur were crossed with pure breeding straight haired guinea pigs with white fur. a. State the genotype and the phenotype of the F1 individuals produced as a result of this cross.b. Two F1 offspring were mated together. Calculate the expected ratio of phenotypes in the F2 generation.c. Show the completed Punnett square below.
2. In terms of pea plant height, tall plants (T) are dominant over dwarf plants (t). Purple flowers (P) are dominant over white flowers (p). Create a Punnett square that shows all of the possible offspring that could occur from breeding the following: a.) Plant 1: Heterozygous dominant for plant height, homozygous dominant for flower color b.) Plant 2: Heterozygous dominant for plant height, homozygous recessive for flower color c.) Include the percentage/ratio of occurrence for each phenotype.
17. Three recessive traits in aardwolf (a real animal) are stripe-less (s), dwarf (d), and fluffy mane (f). A stripe-less and fluffy female aardwolf mates with a dwarf male aardwolf to produce an F1 that is all WT (has stripes, normal size, and non-fluffy mane). When an F1 is test crossed to a fully recessive aardwolf, the following F2 are produced: Stripe-less, fluffy, normal sized 89 Striped, non-fluffy, dwarf 92 Stripe-less, non-fluffy, dwarf 1 Striped, fluffy, normal sized 2 11 13 19 20
23. In horses, black color is influenced by the dominant allele B and chestnut coat color is influenced by the recessive allele b. Trotting gait is due to a dominant allele T, pacing gait to the recessive allele t. A black trotter who is homozygous for both traits is crossed to a chestnut pacer. a. What are the genotypes of the Pgeneration? b. What will be the genotype and phenotype of the F1 generation? c. Draw a punnett square showing the cross of two F1 generation horses. What is the phenotypic ratio of all the combinations?