Flashcards in Cell Cycle Deck (21):
All body cells except gametes; contain 46 chromosomes
Sperm and egg cells; contains 23 chromosomes
What attaches two sister chromatids?
Division of the cells nucleus
The division of the cells cytoplasm
The phase in which the cell grows while carrying out cell functions unique to its cell type
The cell continues to carry out its unique functions but duplicates its chromosomes. It faithfully makes a copy of DNA that makes up the cells chromosomes
The period after the chromosomes have been duplicated and just before mitosis. The cell continues to grow and carry out its functions during this time
Chromatin become more tightly coiled into discrete chromosomes and nucleoli appear. Mitotic spindles begin to form in the cytoplasm
Nuclear envelope begins to fragment, allowing microtubules to attach to the chromosomes. Two chromatids of each chromosome are held together by the centromere, which are attached by kinetochores
Microtubules move the chromosomes to the metaphase plate at the equator of the cell. Centrioles have migrated to opposite poles in the cell, riding along on the developing spindle
Sister chromatids begin to separate, pulled apart by motor molecules. The cell elongates, and nonkinetochore microtubules ratchet apart. By the end of this phase, the opposite ends of the cell contain complete an equal sets of chromosomes
The nuclear envelope reforms around the set of chromosomes, and chromatin fiber of the chromosomes become less condensed.
During this the cytoplasm of the cell is divided. Prokaryotes replicate their genome by binary fission rather than mitosis.
The protein enzymes that control the cell cycle. They exist in the cells at all times but are active only when they are connected to cyclin proteins.
Microtubule organizing center
A radial array of short microtubules extending from each centrosome
The cell cycle clock has these were the cell cycle stops until a go-ahead signal is received
For most cells, which checkpoint seems to be the most important?
G1 checkpoint (this checkpoint will usually allow the cell to complete the S, G2, and M phases and divide)
Two types of regulatory proteins that are involved in cell cycle control
Cyclins and cyclin dependent kinases (Cdks)