Mitosis: the process by which cells reproduce themselves, resulting in daughter cells that contain the same amount of genetic material as the parent cell.
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Cell Division Occurs in a series of stages of phases
Interphase occurs before mitosis begins
Chromosomes are copied (# doubles)
Chromosomes appear as threadlike coils (chromatin) at the start, but each chromosome and its copy(sister chromosome) change to sister chromatids at end of this phase
Prophase
1st step in Mitosis
Mitosis begins (cell begins to divide)
Centrioles (or poles) appear and begin to move to opposite end of the cell.
Spindle fibers form between the poles.
Metaphase 2nd step in Mitosis
Chromatids (or pairs of chromosomes) attach to the spindle fibers.
Anaphase
3rd step in Mitosis
Chromatids (or pairs of chromosomes) separate and begin to move to opposite ends of the cell.
Telophase
4th step in Mitosis
Two new nuclei form.
Chromosomes appear as chromatin (threads rather than rods).
Mitosis ends.
Cytokinesis
occurs after mitosis
Cell membrane moves inward to create two daughter cells – each with its own nucleus with identical chromosomes.
Cell Cycle
DNA associates with special proteins to form more stable structure called chromosomes (different proteins in prokaryotes and eukaryotes, so chromosomes built different)
Chromosomes are found inside nucleus in eukaryotes
Human - 46 chromosomes, 23 pairs (1 set of 23 from egg, 1 set of 23 from sperm)
Each chromosome contains many genes
Gene is a segment of DNA that is responsible for controlling a trait (e.g., coding for a specific protein)
The cell cycle consists of
Mitotic (M) phase (mitosis and cytokinesis)
Interphase (cell growth and copying of chromosomes in preparation for cell division)
Interphase (about 90% of the cell cycle) can be divided into subphases:
G1 phase (“first gap”)
S phase (“synthesis”)
G2 phase (“second gap”)
Distribution of