Teractions between cyclins and cyclin-dependent kinases control the cell cycle. Explain how the presence or absence of inhibitors of cyclin-dependent kinases might play a role in normal cells becoming cancer cells.

Cyclins are proteins that bind to kinases (i.e., cyclin-dependent kinases), by acting as their cofactors.  The cyclin-dependent kinases play critical biological functions such as, for example, the regulation of the cell cycle, mRNA processing, etc. The inhibitors of cyclin-dependent kinases are able to alter the cell cycle progression and thereby inhibit cell death (apoptosis), which is common in cancer cells .

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus