ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
6th Edition
ISBN: 9781260406092
Author: HARTWELL, Leland, HOOD, Leroy, Goldberg, Michael
Publisher: Mcgraw-hill Education/stony Brook University
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 15, Problem 18P
Plant breeders have long appreciated the phenomenon called hybrid vigor or heterosis, in which hybrids formed between two inbred strains have increased vigor and crop yield relative to the two parental strains. Starting in the 1930s, seed companies exploited the cytoplasmic male sterility (CMS) phenomenon in corn that was described in Problem 17 so that they could cheaply produce hybrid corn seed to sell to farmers. This type of CMS
is caused by mutant mitochondrial genomes that prevent pollen formation.
a. | How would CMS aid seed companies in producing hybrid corn seed? |
Dominant Rf alleles of a nuclear gene called Restorer suppress the CMS |
|
a. | Describe a cross generating hybrid corn seed that would grow into fertile (self-fertilizing) plants. (Farmers planting hybrid seed want fertile plants because corn kernels result from fertilized ovules.) |
b | One of the historical challenges in the commercialization of hybrid corn produced through CMS was the maintenance of strains with CMS mitochondria: How could the seed companies keep producing male sterile corn plants if these plants never themselves produced pollen? Suggest a strategy by which the seed companies could continue to obtain male sterile plants every breeding season. |
c. | Are there any potential disadvantages to the use of hybrid corn? If so, what issues might arise? |
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
You are studying a plant with tissue comprising both green and white sectors. You wish to decide whether this phenomenon is due (1) to a chloroplast mutation of the type considered in this chapter or (2) to a dominant nuclear mutation that inhibits chlorophyll production and is present only in certain tissue layers of the plant as a mosaic. Outline the experimental approach that you would use to resolve this problem.
In a species of tree, seed color is determined by four independently
assorting genes: A, B, C, and D. The recessive alleles of each of these genes (a, b,
C, and d) produce abnormal enzymes that cannot catalyze a reaction in the
biosynthetic pathway for seed pigment.
This pathway is diagrammed as follows:
A
White precursor
Yellow ----Orange----- Red
---
Blue
When both red and blue pigments are present, the seeds are purple. Trees with
the genotypes Aa Bb Cc Dd and Aa Bb Cc dd were crossed.
(a) What color are the seeds in these two parental genotypes?
(b) What proportion of the offspring from the cross will have white seeds?
(c) Determine the relative proportions of red, white, and blue offspring from the
cross.
During the course of a research project you generate a gene knockout line in Arabidopsis thaliana to study the function of a gene you believe plays a crucial role in cellular metabolism. You note that the initial transformants are a bit smaller than normal. In subsequent crosses you are unable to isolate homozygotes for the knockout allele. Heterozygotes in subsequent generation are still a bit smaller than the homozygous wild type plants. Explain what is happening.
Chapter 15 Solutions
ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
Ch. 15 - Match each numbered item with the most closely...Ch. 15 - Assuming human cells have on average 1000...Ch. 15 - Reverse translation is a term given to the process...Ch. 15 - The human nuclear genome encodes tRNAs with 32...Ch. 15 - The human mitochondrial genome includes no genes...Ch. 15 - How do you know if the halibut you purchased at...Ch. 15 - Is each of these statements true of chloroplast or...Ch. 15 - Suppose you are characterizing the DNA of a...Ch. 15 - An example of a gene-targeting DNA plasmid vector...Ch. 15 - Which of the following characteristics of...
Ch. 15 - The Saccharomyces cerevisiae nuclear gene ARG8...Ch. 15 - The so-called hypervariable regions HV1 and HV2 of...Ch. 15 - Suppose a new mutation arises in a mitochondrial...Ch. 15 - Describe at least two ways in which the...Ch. 15 - Why are severe mitochondrial or chloroplast gene...Ch. 15 - Suppose you are examining a newly found plant...Ch. 15 - A form of male sterility in corn is inherited...Ch. 15 - Plant breeders have long appreciated the...Ch. 15 - A mutant haploid strain of Saccharomyces...Ch. 15 - Prob. 20PCh. 15 - What characteristics in a human pedigree suggest a...Ch. 15 - The first person in the family represented by the...Ch. 15 - In 1988, neurologists in Australia reported the...Ch. 15 - If you were a genetic counselor and had a patient...Ch. 15 - Kearns-Sayre syndrome KSS, Pearson syndrome, and...Ch. 15 - Many clinically relevant mitochondrial diseases...Ch. 15 - Leigh syndrome is characterized by psychomotor...Ch. 15 - All mutations in mitochondrial genes ultimately...Ch. 15 - How could researchers have determined that the...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- A mutation that breaks which of the following genes would be most likely to produce theanthocyanless phenotype of the green-stem Wisconsin Fast Plants (meaning no purple stems):PAL, CHS, C3H, FLS, or DFR? Explain your reasoning.arrow_forwardWhen two plants belonging to the same genus but different species are crossed, the F1 hybrid is more viable and has more ornate flowers. Unfortunately, this hybrid is sterile and can only be propagated by vegetative cuttings. Explain the sterility of the hybrid and what would have to occur for the sterility of this hybrid to be reversed.arrow_forwardAssume that diploid plant A has a cytoplasm genetically different from that of plant B. To study nuclear–cytoplasmic relations, you wish to obtain a plant with the cytoplasm of plant A and the nuclear genome predominantly of plant B. How would you go about producing such a plant?arrow_forward
- For a haploid fungus, the starting point in the biosynthesis of the amino acid arginine is Compound X, which is always present in and absorbed from the environment. The arginine biosynthetic pathway is: Enzyme A Enzyme B Enzyme Ç Compound X It is know that genes encoding enzymes A and C are on two different chromosomes. Compound Y Compound Z- Arginine A mutant strain of genotype a (lacking only enzyme A) is crossed to a mutant strain of genotype c (lacking only enzyme C) to generate a diploid strain. Sporulation (i.e. meiosis) is subsequently induced in the resulting diploid strain. What proportion of the spores (haploids formed by sporulation) is expected to grow on medium without arginine but supplemented with Compound Y? O 100% 50% 0% 25%arrow_forwardAssume that diploid plant A has a cytoplasm genetically different from that of plant B. To study nuclear–cytoplasmic relations, you wish to obtain a plant with thecytoplasm of plant A and the nuclear genome predominantly of plant B. How would you go about producingsuch a plant?arrow_forwardYou are a developmental geneticist studying flowering time variation in Arabidopsis. You perform a mutagenesis screen to identify mutants in the photoperiod pathway. Given what you know about photoperiodism in Arabidopsis, what phenotype are you looking for and under what photoperiodic conditions would you perform the experiment? delayed flowering in long days delayed flowering in short days same flowering in short days early flowering in short days same flowering in long days early flowering in long daysarrow_forward
- Which of the following depicts an epigenetic change?i. Green, variegated and albino Agave plants differ in photosynthetic pigments due to differential chromatin compaction in cells of various plant types within the species.ii. Flowers of the hybrid produced from a cross of a red-flowered snapdragon by a white-flowered snapdragon are colored pinkiii. Identical twins show dissimilar phenotypes due to changed methylation patterns of the Cytosines and their DNA as a response to different environments a. I onlyb. I and IIIc. II and III d. III onlyarrow_forwardIn roses, the synthesis of red pigment is produced by two steps in a pathway. gene O magenta intermediate - gene P colorless intermediate- red pigment What would the phenotype be of a plant homozygous for a null mutation of gene P? What would the phenotype be of a plant homozygous for a null mutation of gene Q? What would the phenotype be of a plant homozygous for null mutations of genes P and Q? magenta red Match a genotype to each strain. colorless Strain P locus Q locus homozygous null mutation of gene P homozygous null mutation of gene Q homozygous null mutations of genes P and Q Answer Bank plp PIP What F2 ratio is expected from crossing a plant that is homozygous for a null mutation of gene P with a plant that is homozygous for a null mutation of gene Q? Assume independent assortment. 9 colorless : 4 magenta : 3 red 9 red : 4 colorless : 3 magenta O 9 red : 4 magenta : 3 colorlessarrow_forwardIn rice, male sterility is controlled by maternal cytoplasmic elements. This phenotype renders the male part of rice plants (i.e. the stamen) unable to produce fertile pollen; the female parts, however, remain receptive to pollination by pollen from male fertile rice plants. However, the presence of a nuclear fertility restorer gene F restores fertility to male-sterile lines. Give the result(s) of the cross and explain the phenotype of the offspring.arrow_forward
- In sweet peas, the given enzymatic pathway result to pigment formation in the flowers: A dihybrid plant is crossed to a white one which is heterozygous at the “C” locus (provided in the image). What is the genotype of the dihybrid plant? What is the genotype of the white plant? What kinds of flowers, colored or white, are to be expected from the cross above? Include the ratio.arrow_forwardAnthocyanin is a pigment that gives flowers and leaves purple colors. The M gene codes for a transcription factor (Myb) that promotes expression of an enzyme that produces anthocyanin. The W gene codes for a different enzyme (Chs) that allows anthocyanin to be deposited in plant leaves and flowers. The dominant phenotype is the production of functional Myb and Chs. 1) Plants that have the mm genotype do not show any purple color. What is the best explanation for why this is? a) Anthocyanin cannot be deposited into the flowers and leaves b) Anthocyanin is not produced in the plant cells c) The M gene is codominant to the W gene d) The M gene is epistatic to the W gene 2)Assume a plant has the genotype MMww. Would this plant have any purple flowers? a) Yes b) Noarrow_forwardTwo morphotypes of the newly discovered plant in Mt. Banahaw de Lucban were tested for linkage of three genes such as the presence of tendril (t+), dense trichomes (d+), and the presence of secretory cells (sc+). The loci for the mutant genes have been mapped and are separated by the following map distances: t and d = 20CM; d and sc = 12CM. The interference between these genes is 0.4. The first morphotype is located at the lower elevation and is characterized by the absence of tendril, sparse trichome, and absence of secretory cells. On the other hand, the second morphotype is located at the higher elevation and is characterized by the presence of tendril, dense trichome, and presence of secretory cells. Further genetic analysis showed that the morphotypes were true breeding. The two morphotypes were intercrossed and the resulting F1 is testcrossed with the first morphotype. The cross resulted in 1800 progeny. Give the genotypes, phenotypes, and the expected numbers of phenotypes in…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY