TLS Online TPP Program

#Question id: 4018


How does binding of the lac repressor to the lac operator block transcription initiation?

#Unit 3. Fundamental Processes
  1. lac repressor binding blocks RNA polymerase from interacting with DNA at the start site.

  2. lac repressor binding induces a DNase that cleaves the DNA at the transcription start site.

  3. lac repressor binding causes a conformational change in RNA polymerase.

  4. lac repressor binding induces a protease that degrades the sigma subunit of RNA polymerase.

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TLS Online TPP Program

#Question id: 11536

#Unit 6. System Physiology – Plant

IAA has been found to be conjugated to both high- and low-molecular-weight compounds such as,

a) Low-molecular-weight conjugated auxins include esters of IAA with glucose or myo-inositol and amide conjugates such as IAA-N-aspartate

b) High-molecular-weight IAA conjugates include IAAglucan and IAA-glycoproteins found in cereal seeds

c) High-molecular-weight conjugated auxins include esters of IAA with glucose or myo-inositol and amide conjugates such as IAA-N-aspartate

d) Low-molecular-weight IAA conjugates include IAAglucan and IAA-glycoproteins found in cereal seeds

Which of the following is the correct prediction about low-and high-molecular weight ?

TLS Online TPP Program

#Question id: 11537

#Unit 7. System Physiology – Animal

Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of ________.

 I) an autocrine signal

 II) a paracrine signal

 III) an endocrine signal

TLS Online TPP Program

#Question id: 11538

#Unit 7. System Physiology – Animal

Prostaglandins are local regulators whose chemical structure is derived from ________.

TLS Online TPP Program

#Question id: 11539

#Unit 7. System Physiology – Animal

Aspirin and ibuprofen both ________.

TLS Online TPP Program

#Question id: 11540

#Unit 7. System Physiology – Animal

A cell with membrane-bound proteins that selectively bind a specific hormone is called that hormone's ________.

TLS Online TPP Program

#Question id: 11541

#Unit 7. System Physiology – Animal

The steroid hormone aldosterone affects only a small number of cells in the body because ________.