Purdue Bio 241 Final (LeetahC on quizlet)

In Saccharomyces cerevisiae, a cross between a haploid suppressive petite mutant and a haploid wild type results in petite diploid progeny. This is because

The petite mutant contains deletion in mtDNA, which give nonfunctional mutant mitochondria proliferation advantage

The transmission of prion is sensitive to the treatment of

protease

The maternal-effect mutation torso (tor) is recessive. In the absence of the torso protein product, embryogenesis is not completed (missing both head and tail structures). Consider a cross between a female heterozygous for the torso (tor+/tor-) and a male homozygous
for the mutation (tor-/tor-).

What will the phenotype(s) of the progeny be?

All are normal

We have learned about the C. elegans pathways required for proper vulva development in lecture. Based on our discussion, please answer the following questions.

a) What will the phenotype be, if the anchor cell is ablated?

Vulvaless

What is the expected phenotype of loss-of-function in lin-3?

Vulvaless

What would the expected phenotype be if you over-express lin-3?

Multivulva

What is the expected phenotype if you express a mutant let-60 with a mutation analogous to those of oncogenic Ras (let-60 is the worm ortholog of Ras)

Multivulva

To analyze the genes required for C. elegans vulva development, you have made an animal mosaic for lin-3. Please predict the phenotype of the mosaic animal if the anchor cell is lin-3[-] and the vulva precursor cells (e.g. P5.p, P6.p, and P7.p) are wild-type.

Vulvaless

In a different mosaic animal, the anchor cells is wild-type, and the vulva precursor cells are lin-3[-]. What will be the phenotype of this mosaic animal?

wild-type

Predict the phenotype of a fly that is sev- but expresses RasV12 in these R7 precursor cells.

Multiple R7 cells

Predict the phenotype of a fly that is sev- but expresses Boss ectopically (Boss is expressed everywhere)

No R7 cell

Regarding Drosophila bicoid, which of the following statements is incorrect?


Bicoid controls the formation of anterior structures.

Bicoid is a maternal-effect gene.

The localization determinant for bicoid mRNA is in 5'UTR.

Bicoid gene encodes a homeodomain-containing transcription factor.

Bicoid acts as a morphogen.

The localization determinant for bicoid mRNA is in the 3'UTR not the 5'UTR

You have isolated a mutant affecting anterior-posterior patterning of the Drosophila embryo, in which every other segment of the developing mutant embryo was missing. Based on this observation, the mutation is likely be in a

Pair-rule gene

You have cloned a piece of DNA that contains the candidate gene. In situ hybridization using this DNA was performed to determine the expression pattern of this gene during embryogenesis. Based on the discussion in class, you'll expect to see

7 stripes

Regarding Hox genes, which of the following statements is incorrect?

The organization and function of Hox genes are conserved in mammals.

Drosophila contains two Hox gene complexes.

Hox genes encode transcription factors, which include DNA-binding homeodomain.

In Drosophila Hox mutants, the number of segments is affected.

The arrangement of Hox genes on chromosome is co-linear with structures specified by these genes.

The number of segments are not affected in Hox mutants

How is anti-body diversity generated?

The diversity is generated by gene rearrangement in both the immunoglobulin heavy chain and light chain loci

What oncogenic mutation is dominant?

A mutation in E2F that disrupts its ability to bind RB has the potential to create dominant oncogenes

Which gene is known as the guardian of the genome?

p53

Suppose you have the capability to mutate all the copies of Ras genes in these erbB-expressing cells, will this enhance or suppress the ability of erbB to promote tumor progression?

suppress

Suppose you have the capability to mutate the GAP (GTPase activating protein) genes in the erbB-expressing cells, will this enhance or suppress the ability of erbB to promote tumor progression?

Enhance

A homozygous plant with 20 cm diameter flowers is crossed with a homozygous plant of the same species that has 40 cm diameter flowers. The F1 plants all have flowers 30 cm in diameter. In the F2 generation of 512 plants, 2 plants have flowers 20 cm in diameter, 2 plants have flowers 40 cm in diameter and the remaining 508 plants have lowers of a range of sizes in between. Assuming that all alleles involved act additively, how many genes control flower size in this plant?

4

Joe is breeding cockroaches in his dorm room (Do not try this). He finds that the average wing length in his population of cockroaches is 4 cm. He chooses six cockroaches that have the largest wings; the average wing length among these selected cockroaches is 10 cm. Joe interbreeds these selected cockroaches. From earlier studies, he knows that the narrow-sense heritability for wing length in his population of cockroaches is 0.6. What should be the average wing length of the progeny of the selected cockroaches?

7.6

In an assessment of learning in Drosophila, flies may be trained to avoid certain olfactory cues. In one population, a mean of 8.5 trials was required. A subgroup of this parental population that was trained most quickly (mean = 6.0) was interbred and other progeny examined. These flies demonstrated a mean training value of 7.5. What is the narrow-sense heritability for olfactory learning in Drosophila?

0.4

The condition that a human cell has mitochondria of only one type

homoplasmy

Prions:

-protein coded by nuclear genes
-prions responsible for bovine spongiform encephalitis
-mutant prion proteins can induce normal prions to adopt diseased conformation
-transmission of prions are not resistant to protease
-mice with PrP genes deleted are resistant to mutant prion infection

A tissue from the leg bud during chick development is transplanted into the wing bud. Later the transplanted tissues form structures of wing origin. Based on this you can conclude that:

At the time of transplantation, the cell fate of cells in the transplanted tissue has not been determined

A soluble molecule capable of specifying more than one cell type by forming a concentration gradient is known as

A morphogen

best characterizes the event distinguishing germ cells from the somatic cells during C. elegans embryogenesis?

partitioning cytoplasmic factors in asymmetric cell division

What is the key event in the formation of terminal structures during drosophila embryogenesis

Activation of the torso receptor tyrosine kinase

To pinpoint the determinants for bicoid and nanos mRNA localization, you have generated several chimera constructs (fusions) using the lacZ gene. After transgenic wild type flies expressing these constructs are established, you perform RNA in situ hybridization on the embryos using lacZ as a probe. Which of the following constructs will yield lacZ-positive signal at the posterior pole?

lacZ 5'UTR - lacZ coding region - nanos 3'UTR

What best describes the expression of even-skipped during the drosophila embryogenesis

7 stripes

What is the phenotype when the animal is mutant for lin-3 (loss-of-function) and the Pn.p cells express a dominant active let-23 allele?

Multiple vulva structures

What is the phenotype when the Pn.p cells are double mutant for a dominant active let-23 allele adn a let-60- (loss-of-function) allele?

Vulvaless

In C. elegans, let-60 is a target of microRNA let-7. Based on this, what is the effect of let-7- mutation on the phenotype of Pn.p cells expressing let-60V12?

The let-7- mutation enhances the phenotype associated with let-60V12 because the let-60V12 protein level is higher in the absence of let-7.

In C. elegans vulva formation, which of the following genes encodes a small GTPase?

Let-60

In drosophila sevenless (sev) and bride-of-sevenless (boss) are involved in forming the R7 photoreceptor cells in the drosophila eye. The boss proteins are expressed on the surface of R8 cells whereas Sev in the R7 precursor cells

The spacing of R8 cells is achieved by lateral inhubition. Based on this information, whcih of the following molecules likely participates in the specification of R8?

notch

Which of the following phrases best describes this Boss-Sev pathway in R7 photoreceptor cell development?

Juxtacrine signaling

The function of GTPase-activating protein (GAP) is to accelerate the rate of GTP hydrolysis of small GTPases. Based on this, what is the phenotype of a loss-of-function mutation in Drosophila GAP?

Multiple R7 cells

If he R8 cell is genotypically Sev+ and the R7 precursor cells are genotypically sev- what will the phenotype be?

No R7 cell

If the R8 cell is genotypically boss+ and the R7 precursor cells are genotypically boss-, what will the phenotype be?

One R7 cell

Which of the following genes act non-cell-autonomously during R7 determination?

Bride of sevenless

The coiling of snail shell is controlled by a maternal-effect locus, where D (dextral) is dominant and d (sinistral) is recessive. If a dextral male of DD genotype is mated with a dextral female of dd genotype, the progeny phenotype will be:

All sinistral (because only the maternal phenotype is passed on

The inheritance of hereditary retinoblastoma (Rb) is autosomal dominant. This is because:

The probability of remaining wild type Rb beind mutated during heterozygous individuals' lifetime is high

Regarding RB and E2F functions

RB binds to E2F and prevents E2F from entering the nucleus

Regarding cyclin and CDK functions:

-the level of cyclin proteins oscillates with the cell cycle
-the kinase activity of CDK becomes active when complex with cyclins
-the level of different cyclinspeak at different stages of the cell cycle
-CDKs and cyclins are positive regulators of the cell cycle control
-the levels of CDK proteins do not oscillate with the cell cycle

At the G1-S transition the formation of cyclin/CDK complex will

increase the level of E2F proteins in the nucleus

How would you describe PUMA function?

PUMA binds to Bcl2 and released BAX

Describe the function of the BAX gene

BAX forms oligomers to promote programmed cell death

What is an example of a proto-oncogene?

E2F

An example of a tumor suppressor gene

GAP (GTPase activating protein)

What would allIow S phase to process even in the presence of DNA damage?

Loss-of-function mutations in both copies of the p53 gene

Immunoglobulins

-the subunits of immunoglobulins are held together by disulfide bonds
-the gene segments at the immunoglobulin loci undergo somatic recombination
-the juntions of joined segments often contain mutations
-high somatic mutation rates are detected at the immunoglobulin loci
INCORRECT: the joining of J-C segments at the immunoglobulin loci requires both RAG1 and RAG2

B cells are clonal meaning that each B cell expresses only one successfully rearranged immunoglobulin (Ig) This is caused by

allelic exclusion

Regarding T cell receptor

T cell receptor recognizes antigens presented by MHC molecules

Synonymous subsitutions

Synonymous substitutions are typically found in coding sequences

How would you describe over-dominance

Heterozygous individuals have fitness advantages over homozygous individuals

Regarding drosophila homeotic genes

The organization of homeotic genes along the chromosome is co-linear with the structures specified

In human, κ light chain locus (on chromosome 2) has 40 V segments and 5 J segments, whereas λ light chain locus (on chromosome 22) has 30 V segments and 4 J segments. Based on this, how many different light chains can be generated by somatic DNA recombination alone

(405)+(304)=320


(# of V segments # of J segments) + (# of V segments # of J segments)

On chromosome 14, the heavy chain locus contains 51 V segments, 27 D segments, 6 J segments, and 9 C segments. How many different heavy chains can be generated by somatic DNA recombination alone

51276=8262

# of V segments # of D segments # of J segments * # of C segments