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TLS Online TPP Program

#Question id: 2698

Most commonly known hairpin structures are found in _____________

#Unit 2. Cellular Organization

  1. DNA

  2. mRNA

  3. tRNA

  4. Rrna

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TLS Online TPP Program

#Question id: 14686

#Unit 4. Cell Communication and Cell Signaling

This member of the AKAP family, designated mAKAP, anchors both PDE and the regulatory subunit  of PKA to the nuclear membrane, maintaining them in a negative feedback loop that provides close local control of the ATP level and PKA activity.
B- The basal level of PDE activity in the presence of hormone (resting state) keeps cAMP levels below those necessary for PKA activation. 
C- Activation of β-adrenergic receptors causes an increase in cAMP to a level in excess of that which can be degraded by PDE. 
D- The resulting binding of cAMP to the R subunits of PKA releases the active catalytic (C) subunits into the cytosol. Some C subunits enter the nucleus, where they phosphorylate and thus activate certain transcription factors . Other C subunits phosphorylate PDE, stimulating its catalytic activity.
E-  Active PDE hydrolyzes cAMP, thereby driving cAMP levels back to basal levels and causing re-formation of the inactive PKA C-R complex. Subsequent de-phosphorylation of PDE returns the complex to the resting state.
TLS Online TPP Program

#Question id: 9169

#Unit 9. Diversity of Life Forms

In areas of permafrost, stands of black spruce are frequently observed in the landscape, while other tree species are noticeably absent. Often these stands are referred to as "drunken forests" because many of the black spruce often "lean over" (that is, they are displaced from their normal vertical alignment). What is the most likely explanation for the unusual growth of these forests in this marginal habitat?
TLS Online TPP Program

#Question id: 11845

#Unit 6. System Physiology – Plant

IAA Is synthesized from__
TLS Online TPP Program

#Question id: 12239

#Unit 10. Ecological Principles

The figures above show the results of an experiment in which two microbial species, A and B, were grown in three treatments. In treatment I, species A was grown alone. In treatment II, species B was grown alone. In treatment III, both species were grown together at the same starting densities as in (I) and (II). The results suggest the interaction is best described as
TLS Online TPP Program

#Question id: 5218

#Unit 11. Evolution and Behavior

Several of the different globin genes are expressed in humans, but at different times in development. What mechanism could allow for this?