Cell Cycle

What is the cell cycle?

series of events that cells go through as they grow and divide. Orig cell creates 2 identical cells

DNA

Genetic info stored within nucleus

Chromatin

Loosely packed, relaxed, spaghetti like DNA. Seen during interphase

Chromosome

Tightly packed and condensed DNA. Seen during mitosis

Sister chromatids

Paired chromatids formed when chromosomes replicate. Connected by a region in center called centromere

Somatic cell

Any non reproductive cells have 46 chromosomes. 23 from each parent

2 main parts of cell cycle

interphase and mitosis & cytokinesis

Interphase

Cell grows & duplicates its DNA. Prepares 4 cell division

Mitosis

DNA in nucleus divided into 2 identical cells. Active cell division. Genetic material is duplicated

Cytokinesis

division of the cytoplasm into 2 identical daughter cells.

G1 phase (growth 1)

Cell grows, cell organelles duplicate

S phase (synthesis)

46 chromosomes duplicated by cell. DNA synthesized

G2 phase (growth 2)

Cell grows & prepare 4 division

G1 checkpoint

Check for DNA dmg before duplication

G2 checkpoint

Checks to make sure DNA is correctly duplicated

M checkpoint

Check to make sure chromosomes are separated into 2 cells equally

Prophase

first and longest phase of mitosis, during which the chromosomes become visible and nuclear membrane dissolves. Spindle fibres form

Metaphase

second phase of mitosis, during which the chromosomes line up across the center of the cell. Spindle fibres attach to chromosomes at their centromeres

Anaphase

the third phase of mitosis, during which chromosome pairs separate and move toward opposite ends of cell

Telophase

Final stage of mitosis; nuclear membranes form around each set of chromosomes. Cell appears to have 2 nuclei