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TLS Online TPP Program

#Question id: 12538

Some global warming models predict that, if permafrost in the tundra regions in the northern hemisphere melts, atmospheric CO2  levels will increase. Which of the following statements best explains this prediction?

#Unit 10. Ecological Principles
  1. The heat released by  the melting  of  the ice  on  such a  vast scale will  cause atmospheric CO2  saturation levels to increase.
  2. All of the tundra producers will die if the permafrost melts, and because the tundra regions are vast in the northern hemisphere the tundra plants will not take part in photosynthetic removal of atmospheric CO2
  3. CO2 tied up in the permafrost ice will be released during a thaw.
  4. All  of  the  undecayed organic material would  be  subject to  decomposition following  a  thaw, which  would lead to incredible increase in global cellular respiration, and add to atmospheric CO2
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TLS Online TPP Program

#Question id: 15297

#Unit 5. Developmental Biology

 Which of the following statement is correct regarding mammalian cleavage?
TLS Online TPP Program

#Question id: 15298

#Unit 5. Developmental Biology

In mammalian development Prior to blastocyst formation, each embryonic blastomere expresses ________ transcription factors and appears to be capable of becoming either ICM or trophoblast.
TLS Online TPP Program

#Question id: 15299

#Unit 5. Developmental Biology

Name of transcription factor which are responsible for  pluripotency of  stem cells or stimulate the production of OCT4 and NANOG ;
TLS Online TPP Program

#Question id: 15300

#Unit 5. Developmental Biology

In hippo signaling pathway, the activation of the Cdx2 gene in the trophoblast cells appears to be regulated by the Yap protein, which in turn is a cofactor for the transcription factor Tead4. Tead4 is found in the ________blastocyst
TLS Online TPP Program

#Question id: 15301

#Unit 5. Developmental Biology

Initially, the morula does not have an internal cavity. However, during a process, cavitation, the trophoblast cells secrete fluid into the morula to create a blastocoel, these 
membranes of trophoblast cells contain_______?
TLS Online TPP Program

#Question id: 15302

#Unit 5. Developmental Biology

FOXP1 is a transcription factor which stimulate the production of Oct4 and Nanog and establish pluripotency. Which of the following statements are correct regarding to the mechanism of alternative splicing of FOXP1. 
A. There are two isoforms of the FoxP1 protein, One is the product of an mRNA spliced to include a particular exon, 18b, while the other splicing variant carries exon 18a.
B. When alternative splicing generates a form including exon 18b in place of 18a, the resulting isoform (FOXP1-ES) binds to a different DNA sequence and thus controls expression of a different set of genes.
C. The protein encoded by the exon 18b– carrying mRNA is called FOXP1-ES it fails to stimulate expression of OCT4 and NANOG and instead actives genes that promote differentiation. 
D. The exon 18a– containing form encodes FOXP1 itself, and this has the opposite effect: this activates genes that promote dedifferentiation, and thus stimulates iPS cell formation.