SYNTHESIZE YOUR KNOWLEDGE
Insects have three thoracic (trunk) segments. While researchers have found insect fossils with pain of wings on all three segments, modern insects have wings or related structures on only the second and third segment. It turns out that in modern insects, Hox gene products act to inhibit wing formation on the first segment The treehopper insect (above) is somewhat of an exception. In addition to having wings on its second segment, the treehopper's first segment has an ornate helinet that resembles a set of thorns, which a recent study has found to be a modified, fused pair of "wings." the thorn-like structure helps to Camouflage the treehopper In tree branches, thus reducing its risk of predation. Explain how changes in gene regulation could have led to the evolution of such a structure.
Want to see the full answer?
Check out a sample textbook solutionChapter 21 Solutions
Campbell Biology 11th Edition - Valuepack
Additional Science Textbook Solutions
Genetics: From Genes to Genomes
College Physics: A Strategic Approach (3rd Edition)
Laboratory Manual For Human Anatomy & Physiology
SEELEY'S ANATOMY+PHYSIOLOGY
Biology: Life on Earth with Physiology (11th Edition)
- A C. elegans (nematode) gene called par-1 helps todetermine the AP axis of the animal early in development. Scientists determined that par-1 is pleiotropic—it also has a later function in forming the vulva of theadult animal. How could researchers circumvent thelethality of par-1− mutants to observe the later function of the par-1 gene? (Hint: C. elegans larvae caneat bacteria expressing RNAi for any gene.)arrow_forwardYou are studying Hox genes in crane flies (Leptotarsus testaceus). The cranefly genome is sequenced, and in craneflies. Using your understanding of Hox genes, design an experiment testing where the homolog of the EVE gene is expressed in cranefly embryos. you have access to this sequence. You are interested in studying the EVE genearrow_forward. Complete genome sequences indicate that the humangenome has roughly 27,000 genes, while the worm(nematode) genome has about 22,000 genes. Explainhow the human genome with only about 20% moregenes can encode a creature enormously more complex than the worm.arrow_forward
- You have identified a Drosophila gene that is expressed exclusively in the odd-numbered "stripes" in the cellular blastoderm. Assuming that this gene is not redundant, what would be the most likely phenotype cause by a loss-of-function mutation in this gene? an embryo missing odd numbered segments an adult fly with a second pair of wings instead of halteres an embryo with two anterior ends an embryo missing even-numbered segments an embryo missing larval segments 3-10arrow_forwardThe homeotic mutation Antennapedia causes mutant Drosophila to have legs in place of antennae and is a dominant gain-of-function mutation. List all the properties of such mutations. How does the Antennapedia gene change antennae into legs?arrow_forwardFigure 13-7 illustrates the expression of the Ultrabithorax(Ubx) Hox protein in developing flight appendages.What is the relationship between where the protein isexpressed and the phenotype resulting from the loss ofits expression (shown in Figure 13-1)?arrow_forward
- Insect wings are coded for by the same gene that creates... A. internal air branches (trachea) B. Their cuticle C. their antennae D. parts of crustacean appendages, like legsarrow_forwardAnd see the following question correctly thanksarrow_forward) Explain how and why dorsal/ventral polarity will be affected in fly Question 3 (1. embryos carrying the following mutations; also in each case darken in the area of the cells in the cross-sectional view of the fly embryo which are expected to express the paulie gene. D = dorsal; V = ventral. a) a mutation which results in the deletion of the cytoplasmic domain of the Cookie protein. b) A mutation which results in a constitutively active Bombe protein, i.e. the Bombe protein is always in an activated state. c) A mutation which causes the Pickle protein to be retained in the cytoplasm of the embryo.arrow_forward
- Propose a hypothesis that could explain the following observation. A graduate student performing studies on mutations in drosophila (fruit flies) discovered a strain of flies with a silent mutation in the gene controlling the shape of the wings. Further investigation has shown that this mutation is lethal in flies who are homozygote. Flies that are homozygote wild type or heterozygote can develop and are able to survive.arrow_forwardBriefly describe how the bicoid and nanos genes help to determine the anterior–posterior axis of the fruit fly.arrow_forwardSuppose that Drosophila has 3 thoracic hox genes (PS3 - PS5) and 10 abdominal hox genes (PS6 - PS15) corresponding to the three thoracic and 10 abdominal body segments. What would happen to the development of the fly if you inactivated PS6 and PS7? Explain in detailarrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning