You and your lab partner have isolated 20 new mutant yeast strains that are defective in synthesis of threonine, an amino acid. These Thr- mutants do not grow on minimal medium, but they do grow on minimal medium supplemented with threonine. Ten of your Thr- mutants (numbered 1 through 10) were isolated in a strain of mating type a (MAT a). The other 10 Thr mutants (numbered 11 through 20) were isolated in a strain of mating type α (MAT α). You and your lab partner cross each of the MAT a strains to each of the MAT α strains, and you include crosses to the appropriate wild-type strains. Your experimental observations are shown in the table below, where (-) indicates diploids that did not grow on minimal medium and (+) indicates diploids that did grow on minimal medium.

Which mutations are recessive?

TLS Online TPP Program

#Question id: 28511

#Unit 5. Developmental Biology

Find out the incorrect prediction about the fgf10 during limb generation?

TLS Online TPP Program

#Question id: 28512

#Unit 5. Developmental Biology

Fgf10 is function as positive feedback factor in different ways such as___

a) to maintain the activation of both Wnt2b and Tbx5

b) to tells the surface ectoderm to continue to make Fgf8, and the surface ectoderm continues to tell the underlying mesoderm to make Fgf10

c) to maintain the activation of both Wnt3a and Tbx4

d) to tell the mesenchyme cells directly beneath it to continue making Fgf10

TLS Online TPP Program

#Question id: 28513

#Unit 5. Developmental Biology

To induce Fgf8 expression by Fgf10, once Fgf8 is made in the surface ectoderm, the surface ectoderm elongates to physically become the AER. which one is the main functions of the AER?

TLS Online TPP Program

#Question id: 28514

#Unit 5. Developmental Biology

During which condition further development of distal limb skeletal elements ceases?

TLS Online TPP Program

#Question id: 28515

#Unit 5. Developmental Biology

Which of the following is correct prediction, If an extra AER is grafted onto an existing limb bud?

TLS Online TPP Program

#Question id: 28516

#Unit 5. Developmental Biology

The two-experiment performed by a scientist with a forelimb mesenchyme and seeing their results;

I-leg mesenchyme is placed directly beneath the wing AER

II-limb mesenchyme is replaced by non-limb mesenchyme beneath the AER

Conclusion of these experiment are seeing; 

a) distal hindlimb structures develop at the end of the limb

b) supernumerary structures are formed, usually toward the distal end of the limb

c) the AER regresses and limb development ceases

Select the correct result about these experiments-