CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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physical and chemical cues
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kinases and cyclins
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cell specialization
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cell cycle checkpoints
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Detailed explanation-1: -Cell cycle progression is positively regulated by a family of protein kinases referred to as the cyclin-dependent kinases (CDKs).
Detailed explanation-2: -Cdks, cyclins, and the APC/C are direct regulators of cell cycle transitions, but they aren’t always in the driver’s seat. Instead, they respond to cues from inside and outside the cell. These cues influence activity of the core regulators to determine whether the cell moves forward in the cell cycle.
Detailed explanation-3: -The cell cycle is controlled at three checkpoints. The integrity of the DNA is assessed at the G1 checkpoint. Proper chromosome duplication is assessed at the G2 checkpoint. Attachment of each kinetochore to a spindle fiber is assessed at the M checkpoint.
Detailed explanation-4: -The second group comprises four CDKs-Kin28, Srb10, Bur1 and Ctk1-each activated by a single specific cyclin (Figure 1). These cyclins are usually not regulated in a cell-cycle-dependent manner, and the members of this second group of CDKs are involved in the control of gene transcription.