Flashcards

AP Biology chapter 9 cell division

Kimberlee Hernandez English 12 cards

Cards in this deck (12)

1Why do cells divide? (4)-replace dead or damaged cells
-growth of multicellular organisms (making more cells)
-reproduction
-"DNA overload
2Mitosis functions inGrowth
3DNA and proteins Packaged as chromatic-euchromatin: lightly packaged (de condensed)
-heterochromatin: tightly packaged (condensed)
4Interphase (4)•growth
•normal cell functions
•chromosomes copied
•prepare to divide
5Anchorage dependence•most cells divide only when attached to a surface
6Density-dependent inhibition•cells continue dividing until they touch one another then stop
7Internal regulators•cycling increase causes cell to divide
8Internal regulator : p53 geneHalts cell cycle until DNA is repaired
9External regulators•growth factors (growth hormones)
-proteins secreted by cells that stimulate other cells to divide
-signal cell to divide
10CheckpointsHelp regulate the cell cycle
11Cancer cells-Have abnormal cell cycles
-caused by mutant genes regulating the cell cycle (p53 gene)
-ignore checkpoints and other regulatory mechanisms
-divide excessively, can form tumors
12Malignant tumorsCan invade other tissues and may kill the organisms