2007-02-09 11:59:34 · 5 answers · asked by kimzzz 1 in Science & Mathematics ➔ Biology
The cell cycle have things called checkpoints, which stop the cell cycle until the certain regularatory molecules let the cell cycle proceed. The actual molecules that regulate the cell cycle are called cyclin dependent kinases, which are enzymes whose activity depends on the levels of a class of proteins called cyclins. Cyclin concentration occur in cycles which correspond to the cell cycle. One example of a Cdk is MPF (maturation promoting factor), which allows cells to get past the G2 checkpoint and into the M phase.
2007-02-09 13:06:16 · answer #1 · answered by kz 4 · 1⤊ 0⤋
the cell cycle is controled by proteins at the following checkpoints: g1, g2, and Mitosis
2007-02-09 20:03:46 · answer #2 · answered by Chucky333 2 · 0⤊ 1⤋
Cyclins!
2007-02-09 22:23:38 · answer #3 · answered by Doctor J 7 · 1⤊ 0⤋
Enzymes, also known as proteins. They control all chemical reactions, and act as catalysts sometimes, which means they speed up chemical reactions.
2007-02-09 20:06:48 · answer #4 · answered by luv_2eat_chocolate 3 · 0⤊ 1⤋
enzymes
2007-02-09 20:02:22 · answer #5 · answered by ecolink 7 · 0⤊ 1⤋