TLS Online TPP Program

#Question id: 12643


Which of the following is the first polypeptide hormone discovered in plants?

#Unit 6. System Physiology – Plant
  1. portosystemic
  2. jasmonic acid
  3. systemin
  4. salicylic acid
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TLS Online TPP Program

#Question id: 4649

#Unit 11. Evolution and Behavior

Which statement best describes the evolution of pesticide resistance in a population of insects?

TLS Online TPP Program

#Question id: 23312

#General Aptitude

It is the daily routine that some students bring undesirable food items from the school-gate. You are full of sorrow to see this condition of your students. What is its remedy?

TLS Online TPP Program

#Question id: 4997

#Unit 11. Evolution and Behavior

If one organ is an exaptation of another organ, then what must be true of these two organs?

TLS Online TPP Program

#Question id: 4973

#Unit 11. Evolution and Behavior

Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. It apparently lived in arid regions, and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous. The dicynodonts had two large tusks, extending down from their upper jaws; the tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record, these pig-sized organisms were the most common mammal-like reptiles of the Permian.Which of Lystrosaurusʹ features help explain why these organisms fossilized so abundantly?

I. the presence of hard parts, such as tusks

II. its herbivorous diet

III. its persistence across at least two geological eras

IV. its widespread geographic distribution

V. its mixture of reptilian and mammalian features

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.