1. S phase- DNA replication
Mitosis:
the cell’s nucleus and nuclear material divide; includes four sub-stages.
Prophase
1st and longest phase of mitosis
Chromatin condenses into chromosomes
(chromosomes become visible)
Nuclear envelope/membrane
disappears
Centrioles migrate to poles
Spindles are formed
Metaphase
Chromosomes line up in the
middle of the cell
Each chromosome is attached
to spindles
Anaphase
Chromosomes are pulled apart
Chromatids are pulled to
opposite poles
Telophase
chromatids reach poles
2 new nuclei start to
form
Chromosomes start to
unwind
Spindles disappear
Cytoplasm begins to divide; cell plate forms
Cell Cycle Notes
Steps in a cell’s life cycle which lead up to a cell dividing into two genetically identical daughter cells G0
a phase of the cell cycle where the cells no longer divide
Interphase
the cell grows, carries out cellular functions, and replicates its DNA. Longest phase of cell cycle
G1- Cell Growth
Cell increases in size.
Makes new proteins and organelles
S phase- DNA replication
Chromosomes are copied.
New DNA molecules are made
G2-Final Growth Phase
Shortest phase
Check for mistakes in new DNA
Prepare for nuclear division (mitosis)
Cytokinesis
cell’s
cytoplasm
divides,
creating two new cells

2. Spindle – microtubule that helps separate chromosomes
Key Vocabulary:
Chromosome – contains genetic information (DNA) passed from one generation to the next
Spindle – microtubule that helps separate chromosomes
Centrioles – help to organize cell division
Chromatin – protein-bound DNA within the nucleus
A – Centromere:
center of chromosome
B – Chromatids: two
identical “sister” parts
of the chromosome
Key Points:
Cell Cycle includes:
1.Interphase (G1, S, G2)
2.Mitosis (Prophase, Metaphase, Anaphase, Telophase)
3. Cytokinesis
Ends in 2 daughter cells with identical chromosomes and chromosome numbers