Results (a) Wild-type flower (b) Class A mutants (c) Class B mutants (d) Class C mutants Stamen Carpel Sepal- Petal- Whorl 1: Sepals Whorl 2: Petals Whorl 3: Stamens Whorl 4: Carpels Whorl 1: Carpels Whorl 2: Stamens Whorl 3: Stamens Whorl 4: Carpels Whorl 1: Sepals Whorl 2: Sepals Whorl 3: Carpels Whorl 4: Carpels Whorl 1: Sepals Whorl 2: Petals Whorl 3: Petals Whorl 4: Sepals Conclusion: In wild-type flowers: Gene Product Class A gene products - Class A + class B gene products- Class B+ class C gene products Class C gene products Flower whorl affected sepals in the 1st whorl petals in the 2nd whorl stamens in the 3rd whorl carpels in the 4th whorl 22.15 Analysis of homeotic mutants in Arabidopsis thalian led to an understanding of the genes that determine floral structures in plants.

Looking at Figure 11-9, why were partial diploids essential for establishing the trans-acting nature of the Lacrepressor? Could one distinguish cis-acting from transacting genes in haploids?

If a winter-annual strain of Arabidopsis is grown in a greenhouseand not exposed to cold temperatures, its ability to flower is inhibited.Which gene is responsible for this inhibition?

Can you answer part a-c if its true or false  a) the AP3 and PI show auto- and cross-regulatory interactions, as well as they form obligate heterodimers to carry out the B class gene function. Therefore, if there is no PI expression, AP3 expression alone is not sufficient for establishing the petal and stamen identities.   b) Angiosperm is a group of plants whose seeds are borne within a mature ovary (fruit).   c) The organ in different organisms under every variety of forms and functions due to evolutionary development from the same or a corresponding part in a common ancestor is homologous.

Discuss the morphological differences between the parasegments and segments of Drosophila. Discuss the evidence, providing specific examples, that suggests the parasegments of the embryo are the subdivisions for the organization of gene expression.

You conduct an experiment to study the expression of the S protein through the tissues of your favorite plant (Arabidopsis thaliana). The morning of the experiment you inject in the leaves a messenger RNA that codes for the synthesis of a single protein made of two parts that are attached to each other: the functional S protein and a red fluorescent protein tag (RFP). You perform two cross sections of the same root, one section at the start of the experiment (time = Oh; corresponding to the time of injection) and one section in the afternoon (time = 8h). Through fluorescent microscopy you observe a change in the coloration inside the cells of the root's central tissues (as indicated by the arrows): from no coloration (time = Oh) to red (time = 8h). • The cells of the central tissues in the roots do not have nuclei or ribosomes. How can you explain this change of coloration? Please provide a cellular feature that can lead to this. • What is one advantage of using an RFP-tag in an mRNA?…

In addition to C. elegans and Drosophila, Zebrafish are also another model organism - and have a spine. We're interested in two phenotypes, a curved spine and a gene that causes skin tumors to form on the fish's skin. We'd like to know if we could use the curved spine as an indicator if a fish may develop tumors (if the genes are linked). We'll assume that each of these traits is controlled by a single gene where: a curved spine is the result of a dominant allele S (and a normal spine is the result of recessive alleless), ⚫ and tumor growth is the result of a recessive allele t (and no tumor growths are a dominant T allele). A testcross is performed with a fish that is heterozygous for both genes and the resulting progeny are given below. TtSs x ttss curved spine & no tumors curved spine & tumors normal spine & no tumors 27 45 normal spine & tumors 30 SUN 50 Are these two genes following Mendelian inheritance patterns? Use Chi-Squared analysis to test them. x2 = (0-6)² 1. X2 value:…

What will be the flower structure of a plant in which expression of the following genes is inhibited in the specified whorls? Q. Expression of class A genes is inhibited in the second whorl, but not in the first whorl.

Briefly explain the regulatory interactions between these three classes of patterning genes (gap, pair rule, segment polarity).  What is the temporal order of action and how do the different classes of genes regulate each other?

In the nematode C. elegans, some worms have blisteredcuticles due to a recessive mutation in one of the bligenes. Someone studying a suppressor mutation thatsuppressed bli-3 mutations wanted to know if it wouldalso suppress mutations in bli-4. They had a strain thatwas homozygous for this recessive suppressor mutation,and its phenotype was wild type.a. How would they determine whether this recessivesuppressor mutation would suppress mutations in bli-4?In other words, what is the genotype of the wormsrequired to answer the question?b. What cross(es) would they do to make these worms?c. What results would they expect in the F2 if(1) it did act as a suppressor of bli-4?(2) it did not act as a suppressor of bli-4?