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TLS Online TPP Program

#Question id: 10910

In early research on phloem translocation, both active and passive mechanisms were considered. All theories, both active and passive, assume an energy requirement in both sources and sinks. What will be the INCORRECT explanation of active and passive mechanism?

#Unit 6. System Physiology – Plant
  1. The passive mechanisms of phloem transport further assume that energy is required in the sieve elements of the path between sources and sinks

  2. In active mechanism required energy is simply to maintain structures such as the cell plasma membrane and to recover sugars lost from the phloem by leakage

  3. The active theories, postulate an additional expenditure of energy by path sieve elements in order to drive translocation itself
  4. The pressure-flow model is an example of a passive mechanism
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TLS Online TPP Program

#Question id: 2290

#Unit 1. Molecules and their Interaction Relevant to Biology

The cytoskeleton includes all of the following except
TLS Online TPP Program

#Question id: 1586

#Unit 4. Cell Communication and Cell Signaling

In which of the cases would the precaution likely be taken to give the mother anti-Rh antibodies before delivering her baby?
TLS Online TPP Program

#Question id: 4553

#Unit 3. Fundamental Processes

The NtrC protein (nitrogen regulatory protein C)—stimulates transcription of the glnA gene, this protein is an activator of σ54-RNA polymerase. Which of the following given characteristics about this protein is incorrect?
TLS Online TPP Program

#Question id: 7110

#Unit 5. Developmental Biology

What may be the molecular trigger that causes cells in the presomitic mesoderm to finally condense into somites?
TLS Online TPP Program

#Question id: 1985

#Unit 4. Cell Communication and Cell Signaling

Which of the following is the last line of defense against an extracellular pathogen?