1. KEY CONCEPT Cell cycle __________ is necessary for ______ ______.

2. ________ and ________ factors _______ cell division.
_______ factors include ________ and ________ signals.
____ ______ are proteins that _______ cell division.
Most mammal cells form a _____ _____ in a culture dish and ___ ________ once they _____ other cells.

3. Two of the most important ______ factors are ______ and _______.
_______ factors _____ ________ factors, which affect the cell cycle.

4. __________ is __________ cell _____.
a ______ feature of _______ organisms
caused by a cell’s production of ____-___________ _______
occurs in __________ of _______
webbed fingers

5. Cell division is ___________ in _____.
Cancer cells form __________ ______ called ______.
_____ ______ remain ________ and can be ______.
________ tumors _________, or break away, and can ___ more ______.
cancer cell
bloodstream
normal cell

6. _____ cells do ___ carry out necessary ________.
Cancer cells come from ______ cells with ______ to _____ involved in cell-cycle _________.

7. ___________ are substances known to _______ ______.
Standard cancer treatments typically ____ both _________ and _______ cells.