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TLS Online TPP Program

#Question id: 18928

With respect to nucleic acid hybridization, which, if any, of the following statements is false?

#Unit 13. Methods in Biology
  1. The probe is a labeled nucleic acid or oligonucleotide that is expected to hybridize to a target DNA sequence within an unlabelled test nucleic acid population.
  2. The probe is a known single-stranded nucleic acid or oligonucleotide that is intended to hybridize to complementary target sequences in a poorly understood nucleic acid test sample.
  3. The object of a hybridization assay is to identify target sequences within a test sample that are related to the probe so that some new information is gained about the target sequences.
  4. During a hybridization assay, a heteroduplex is formed by un-natural base pairing between complementary probe and target sequences that show a sufficiently high degree of base pairing across part or all of their lengths.
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TLS Online TPP Program

#Question id: 12183

#Unit 2. Cellular Organization

Following statements are regarding to regulation of S phase and mitotic cyclin levels in budding yeast.
A. In late anaphase, the anaphase-promoting complex (APC/C) ubiquitinylates S phase and mitotic cyclins.
B. In late anaphase, the anaphase-promoting complex (APC/C) phosphorylates S phase and mitotic cyclins.
C. During exit from mitosis and G1, Cdh1 is dephosphorylated and active; during S phase and mitosis, Cdh1 is phosphorylated and dissociates from APC/C, and APC/C becomes inactive.
D. During exit from mitosis and G1, Cdh1 is phosphorylated and active; during S phase and mitosis, Cdh1 is dephosphorylated and dissociates from APC/C, and APC/C becomes inactive.
E. The G1/S phase CDKs, which themselves are not APC/CCdh1 substrates, phosphorylate Cdh1 at the G1–S phase transition.
F. The G1/S phase CDKs, which themselves are not APC/CCdh1 substrates, ubiquitinylates Cdh1 at the G1–S phase transition.
Which of the following combination is correct?
TLS Online TPP Program

#Question id: 12184

#Unit 2. Cellular Organization

Following graph represent Control of S phase onset in S. cerevisiae by regulated proteolysis of the S phase inhibitor Sic1. 
Which of the following is correct according to graph?
TLS Online TPP Program

#Question id: 12185

#Unit 2. Cellular Organization

Mitotic CDKs affect nuclear envelope components by specific mechanism. Which of the following statement is not related to this mechanism?
TLS Online TPP Program

#Question id: 12186

#Unit 2. Cellular Organization

In 2001, the Nobel Prize in Physiology or Medicine was awarded to three cell cycle scientists. Paul Nurse was recognized for his studies with the fission yeast S. pombe, in particular for the discovery and characterization of the wee1+ gene. What did the characterization of the wee1+ gene tell us about cell cycle control?
TLS Online TPP Program

#Question id: 12187

#Unit 2. Cellular Organization

How cells know whether sister kinetochores are properly attached to the mitotic spindle?
TLS Online TPP Program

#Question id: 12188

#Unit 2. Cellular Organization

The series of events by which APC/C promotes the separation of sister chromatids at anaphase.
A. all the kinetochores have attached to spindle microtubules and the spindle apparatus is properly assembled and oriented.
B. Cdc20 specificity factor associated with APC/C directs it to ubiquitinylate securin and mitotic cyclins. 
C. A protease known as separase cleaves the cohesin subunit Scc1 (Rad21), breaking the protein circles linking sister chromatids.
D. anaphase begins as poleward force exerted on the kinetochores moves the split sister chromatids toward opposite spindle poles.
E. Following securin degradation and a decrease in mitotic CDK activity.
Which of the following series is correct?