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#Question id: 15417

Sequence of amphibian lens induction postulated by experiments on embryos of the frog Xenopus laevis ; EXCEPT

#Unit 5. Developmental Biology

Unidentified inducers (possibly from the foregut endoderm and cardiac mesoderm) cause the synthesis of the Otx2 transcription factor in the head ectoderm during the late neurula stage.
As the neural folds rise, inducers from the anterior neural plate (including the region that will form the retina) induce Pax6 expression in the anterior ectoderm that can form lens tissue.
As the neural folds rise, inducers from the anterior neural plate (including the region that will form the retina) induce Pax6 expression in the anterior ectoderm that can form lens tissue.
The optic vesicle secretes BMP and FGF family paracrine factors, which induce the synthesis of the Sox transcription factors and initiate observable lens formation

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#Question id: 15122

#Unit 8. Inheritance Biology

Which of the following is the best example of overdominance?

TLS Online TPP Program

#Question id: 15137

#Unit 2. Cellular Organization

Most mitochondrial proteins however, are manufactured under the direction of the nucleus. Mitochondria reproduce by

TLS Online TPP Program

#Question id: 15144

#Unit 4. Cell Communication and Cell Signaling

For the stimulation of B-cell responses

TLS Online TPP Program

#Question id: 15145

#Unit 4. Cell Communication and Cell Signaling

Which of the following drug causes autoimmune hemolytic anemia?

TLS Online TPP Program

#Question id: 15146

#Unit 8. Inheritance Biology

You have isolated a set of five yeast mutants that form dark red colonies instead of the usual white colonies of wild-type yeast. You cross each of the mutants to a wild-type haploid strain and obtain the results shown below;

What do these results tell you about each of the mutants?

TLS Online TPP Program

#Question id: 15147

#Unit 8. Inheritance Biology

You have isolated a set of five yeast mutants that form dark red colonies instead of the usual white colonies of wild-type yeast. You cross each of the mutants to a wild-type haploid strain and obtain the results shown below;

you cross each haploid mutant strain to a different haploid mutant of the opposite mating type. From the results shown below deduce as much as you can about which mutations lie in the same gene. Clearly state any remaining ambiguities and suggest some general ways that the ambiguities might be resolved

a) That mutants 1 and 3 form one complementation group and are mutations in the same gene (gene A)

b) That mutations 2 and 5 form a second complementation group and are mutations in a second gene (gene B).

c) That mutations 3 and 5 form a second complementation group and are mutations in a second gene (gene B).

d) The first ambiguity is whether mutant 4 has a mutation in gene A or B, or whether it represents a unique gene.

Which of the following is the correct prediction about mutants?