A young woman is given daily injections of a substance beginning on the 16th day of her normal menstrual cycle and continuing for 3 weeks. As long as the injections continue, she does not menstruate. The injected substance could be which of the following?

TLS Online TPP Program

#Question id: 12182

#Unit 2. Cellular Organization

The cell cycle is controlled by protein kinases that comprise a catalytic subunit and a regulatory subunit. Which of the following statement is correct regarding to these subunits?

TLS Online TPP Program

#Question id: 12183

#Unit 1. Molecules and their Interaction Relevant to Biology

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: 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 1. Molecules and their Interaction Relevant to Biology

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: 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?