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TLS Online TPP Program

#Question id: 1021

Disease Control (CDC) determine that the agent causing the birds to die is the West Nile virus. Outbreaks of this illness have been observed in several other countries in Asia and the Middle East across the last 50 years, but not in the United States. With this information, what would be the best categorization of this infectious agent/disease

#Unit 4. Cell Communication and Cell Signaling

  1. This is clearly a reemerging infection. It's been around for a long time, and it is reappearing in a susceptible population again.

  2. This is clearly a nosocomial infection. It's transmitted from animals to human beings in urban environments.

  3. This is clearly an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population.

  4. This is clearly not a concern to human beings--maybe it's emerging in animals, maybe it's reemerging, maybe it's nosomial. But who cares? It's only in birds.

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TLS Online TPP Program

#Question id: 2896

#Unit 2. Cellular Organization

Different modification states of the residue Lys-9 on the tail of histone H3 could be interpreted to have different meanings. One example of how a histone modification can apparently influence a second modification present nearby is illustrated by the Drosophila HP1 protein. Which of the following statement is correct regarding this kind of epigenetic regulation?
TLS Online TPP Program

#Question id: 2897

#Unit 2. Cellular Organization

The transcription of most protein coding genes in mammals (~70 percent) occurs at a lower rate than at TATA box–containing and initiator-containing promoters and begins at any of several alternative start sites within regions of about 100–1000 bp that have an unusually high frequency of CG sequences. Which one of the following best explains it?
TLS Online TPP Program

#Question id: 2898

#Unit 2. Cellular Organization

The human genome is composed of many different types of DNA sequences, the majority of which do not encode proteins. From the following distribution and amount of each of the various types of sequences determine which of these is CORRECTLY expressed?
TLS Online TPP Program

#Question id: 2899

#Unit 2. Cellular Organization

The H3.H4 tetramers and H2A.H2B dimers each interact with a particular region of the DNA within the nucleosome.

I. Histone H3.H4 tetramers occupy a key position in the nucleosome by binding the middle and both ends of the DNA.

II. The amino-terminal region of H3 most proximal to the histone-fold region forms a fourth a-helix that interacts with the final 13 bp at each end of the bound DNA.

III. The relatively short length of DNA bound by H2A.H2B dimers is sufficient to prepare the DNA for H3.H4 tetramer binding.

IV. The H3.H4 tetramer forms the bottom part of the histone octamer located across the disc from the DNA ends whereas two H2A.H2B dimer occupies the top part.

Which of the following represents the correct binding of the histones with the DNA?
TLS Online TPP Program

#Question id: 2900

#Unit 2. Cellular Organization

Which of the following statement is INCORRECT from the set of statements given below?
TLS Online TPP Program

#Question id: 2901

#Unit 2. Cellular Organization

HOTAIR is a lncRNA whose gene is found in the HoxC cluster in humans, but it acts by regulating expression of the HoxD genes on another chromosome (in trans) by recruiting to that locus Polycomb Repressive Complex 2 (PCR2). Which of the following processes is incorrect regarding this regulation?