Concept explainers
One of the autosomal loci controlling eye color in fruit flies has two alleles: one for brown eyes and the other for red eyes. Fruit flies from a true-breeding line with brown eyes were crossed with flies from a true-breeding line with red eyes. The F1 flies had red eyes. What conclusion can be drawn from this experiment? (a) these alleles underwent independent assortment (b) these alleles underwent segregation (c) these genes are X-linked (d) the allele for red eyes is dominant to the allele for brown eyes (e) all the preceding are true
Introduction: Locus (pl:loci) is the specific location of the gene in the chromosome. Alleles are variants of a gene. The allele that masks the expression of the other allele in heterozygous form is called the dominant allele.
Answer to Problem 1TYU
Correct answer: When fruits flies of true-breeding line with brown eyes are crossed with fruits flies of true-breeding line with red eyes, the F1 had red eyes that show that the allele for red eyes is dominant to the allele for brown eyes. Therefore, option (d) is correct.
Explanation of Solution
Reason for the correct answer.
When true breeding parents are crossed where one parent is homozygous for one allele and the other parent is homozygous for another allele, the trait expressed in the F1 generation is the dominant allele. When applying the above principle for the given question, where fruits flies of true-breeding line with brown eyes are crossed with fruits flies of true-breeding line with red eyes, the F1 will have red eyes. This shows that the allele for red eyes is dominant to the allele for brown eyes.
Option (d) is given as “the allele for red eyes is dominant to the allele for brown eyes”.
When fruits flies of true-breeding line with brown eyes are crossed with fruits flies of true-breeding line with red eyes, the F1 will have red eyes that show that the allele for red eyes is dominant to the allele for brown eyes. Therefore, option (d) is correct.
Reasons for the incorrect statements.
Option (a) is given as “these alleles underwent independent assortment”.
Independent assortment can be explained with two traits only. Here, only one trait is mentioned, that is eye color, therefore, they can show only segregation, not independent assortment. Hence, option (a) is incorrect.
Option (b) is given as “these alleles underwent segregation”.
This option is correct, yet the most suitable option will be option (d) as the law of segregation has proved right for single traits. This experiment reveals the dominant allele more than segregation. Hence, option (b) is incorrect.
Option (c) is given as “these genes are X-linked”.
The question mentions that these alleles are present in autosomal loci and therefore, they cannot be X-linked. Hence, option (c) is incorrect.
Option (e) is given as “all the preceding are true”.
Option (d) is the most suitable answer followed by option (b). The other options are incorrect. Hence, option (e) is incorrect.
Hence, options (a), (b), (c), and (e) are incorrect.
When fruits flies of true-breeding line with brown eyes are crossed with fruits flies of true-breeding line with red eyes, the F1 will have red eyes that show that the allele for red eyes is dominant over the allele for brown eyes.
Want to see more full solutions like this?
Chapter 11 Solutions
BIOLOGY >PRINT UPGRADE<
- Using information from the primary literature (several references have been provided as a starting point below) please answer the following question: Based on your review of the literature on rewilding, what are the major scientific pros and cons for rewilding? Please note that the focus of this assignment are the (biological) scientific issues associated with rewilding. As will be discussed in class, there are a number of non-scientific issues involved or implicated in rewilding, all ultimately affecting the public acceptability of rewilding. Although these issues are important – indeed, critical – in this assignment you should focus on the biological science issues and questions. Details: You must enumerate at least two pros and at least two cons. Your answer should be no more than 500 well-chosen words, excluding references. Think carefully about how best to organize and structure your answer. Aim for high information density: say a lot, but say it succinctly. Recall Nietzche’s…arrow_forwardNow draw a rough sketch of what the control data might look like if in addition to the specific binding, there was also a considerable amount of nonspecific binding (again using a normal dose/response curve) (do % total bound ligand vs concentration)arrow_forwardWhat are functions of cuboidal cells in the kidney? Select all that apply. Concentration of gases Dilution of chemicals Secretion of molecules Nutrition to tissues Support of tissues Absorption of moleculesarrow_forward
- question1 In plants, epithelial tissue is only found as the outermost cell layer and acts as a barrier. In humans, epithelial tissue is found inside the body as well as on the surface. What function(s) does/do epithelial tissue carry out in humans? Select all that apply. Waste storage Filtration Oxygen transport Protection Diffusion Osmosis Absorptionarrow_forwardWhat words best describes this organism? a. Unicellular/nonmotile Ob. unicellular/motile c. colonial/nonmotile d. colonial/motile e. multicelluar O f. siphonous g. none of thesearrow_forwardIdentify the phylum or class. a. Euglenophyta b. Dinoflagellata c. Bacillariophyceae d. Oomycetes e. Phaeophyceae O f. Myxomycota g. Xanthophyceae ○ h. Chrysophyceae i. Dictyosteliomycota O j. Rhodophyta Ok. Chlorophyceaens I. Charophyceaensarrow_forward
- What is produced inside the indicated structure (Fucus). a. eggs O b. antheridia ○ c. sperm d. zygotes e. none of thesearrow_forwardGreen Algae, as a group, is actually paraphyletic with one subgroup more closely related to higher plants than the other. Which of the following green algae groups is more closely related to higher plants: a. Charophyceans b. Chlorophyceans c. Rhodophyta d. Xanthophyceansarrow_forwardA single-celled green algal genus that is motile with 2 flagella, has a cup shaped chloroplast, and an eyespot: a. Volvox b. Chlamydomonas c. Euglena d. Codiumarrow_forward
- A[n] ___ is produced by members of the Myxomycota when there is a lack of moisture. a. plasmodiocarp b. aethalium c. sclerotium d. plasmodiumarrow_forwardWhich of the following is not true about the life-cycle of Fucus. a. 8 eggs per oogonium b. 64 sperm per antheridium c. eggs are flagellated d. sperm are flagellatedarrow_forwardGreen Algae, as a group, is actually paraphyletic with one subgroup more closely related to higher plants than the other. Which of the following green algae groups is more closely related to higher plants: a. Charophyceans b. Chlorophyceans c. Rhodophyta d. Xanthophyceansarrow_forward
- Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage LearningConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College