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TLS Online TPP Program

#Question id: 10906

The pressure-flow model explains phloem translocation as a flow of solution (bulk flow) driven by an osmotically generated pressure gradient between source and sink.

a) Phloem translocation, both active and passive mechanisms were considered. All theories, both active and passive, assume an energy requirement in both sources and sinks.

b) In sources, energy is necessary to move photosynthate from producing cells into the sieve elements. This movement of photosynthate is called phloem loading.

c) In sinks, energy is essential for some aspects of movement from sieve elements to sink cells, which store or metabolize the sugar. This movement of photosynthate from sieve elements to sink cells is called phloem unloading.

d) The Active mechanisms of phloem transport further assume that energy is required in the sieve elements of the path between sources and sinks simply to maintain structures.

From the given statements find out the correct for pressure-flow model.

#Unit 6. System Physiology – Plant
  1. A, B, C and D       
  2. A, B, and C
  3. B and C only         

  4. A and D only

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TLS Online TPP Program

#Question id: 19524

#Unit 12. Applied Biology

In the DNA-protein complex where central DNA core is surrounded by the N-terminal half of the Cry protein, while the C-terminal half of the protein 
TLS Online TPP Program

#Question id: 16132

#Unit 13. Methods in Biology

You are running a human assisted reproduction clinic and providing state-of-the-art genetic diagnostic services. A married couple who already had a child with cystic fibrosis approach you because they wish to have another child, but only if they can be assured that the child will not have cystic fibrosis. You genotype the woman and discover that she is a heterozygote for Del508, the most common mutation causing cystic fibrosis. You suggest that the couple consider first polar body testing, in which several unfertilized oocytes (each with its first polar body) are retrieved from the woman, the first polar bodies are removed, and PCR tests are conducted on DNA from each of the first polar bodies. The couple agrees, and you obtain the following results:
 
the observation that the polar bodies for oocytes #1 and #5 test positive for both Del508 and the wild type sequence, because
TLS Online TPP Program

#Question id: 3268

#Unit 11. Evolution and Behavior

A population of insects is in Hardy-Weinberg equilibrium for a gene with alleles A = orange and a = yellow eyes. There are 91% orange and 9% yellow individuals in the population. If the fitness of the yellow phenotype suddenly drops to zero, what will be the allele frequency in the next generation?
TLS Online TPP Program

#Question id: 1478

#Unit 4. Cell Communication and Cell Signaling

Caspases are different on the basis of:
TLS Online TPP Program

#Question id: 4380

#Unit 3. Fundamental Processes

Which of the following is NOT true regarding the chromatin-remodeling SWI/SNF complex?