PATHOLOGY

Detailed explanation-1: -The cell cycles of higher eukaryotes are controlled not only by multiple cyclins, but also by multiple Cdc2-related protein kinases. These Cdc2-related kinases are known as Cdk’s (for cyclin-dependent kinases ).

Detailed explanation-2: -Cyclins are proteins that regulate the timing of the cell cycle in eukaryotic cells.

Detailed explanation-3: -Answer and Explanation: Cell cycle regulation is controlled via the action of enzymes call cyclin dependent kinases and cyclins. These enzymes control the progression of the cell through all phases of interphase, as well as mitosis.

Detailed explanation-4: -Cell cycle progression is regulated in part by the sequential activity of various cyclins. The cyclins are regulatory subunits that bind, activate and provide substrate specificity for their catalytic partner serine-threonine kinases, collectively called cyclin-dependent kinases (Cdks) (reviewed in refs. 8 and 9).

Detailed explanation-5: -The main families of regulatory proteins that play key roles in controlling cell-cycle progression comprise the cyclins (cyc) family, their substrates, the cyclin dependent kinases (cdks), the different families of cdk inhibitors (CKI) and the pocket protein retinoblastoma (pRB) family.