Cell Division Notes
Eukaryotic Cells
Somatic Cells: cells that make your _______________ and ________________.
Sex Cells: the ONLY cells that are not somatic; _______________ and
______________ cells (Gametes).
Cell Division
Cell Cycle
In eukaryotes, cell division occurs in two major stages:
 The first stage, ____________________________________________,
is called Mitosis
 The second stage, _________________________________________,
is called Cytokinesis
The cell cycle is the series of events that cells go through as they ___________
and ______________.
____________________ is the period of growth that occurs between cell
divisions. Cells spend most of their life in this phase.
During the cell cycle:
1. A cell grows
2. Prepares for division
3. Divides to form two _____________________________, each of which
begins the cycle again
The cell cycle consists of four phases:
1. __________________
2. __________________
3. __________________
4. __________________
Events of the Cell
Cycle
During G1, the cell:
 Increases in size
(_____________________)
 Synthesizes new proteins and organelles (_______________________)
During S phase, (DNA Replication):
 ___________________________________________
 DNA synthesis takes place
Once a cell enters the S phase, it usually completes the rest of the cycle
During G2, (Second Gap Phase):
 Organelles and molecules required for cell division are produced
 Once G2 is complete, cell will begin M phase - ____________________
Why does
interphase happen?
Cell must grow so that extra organelles and DNA have room in the cell.
DNA
Chromatin – long, thin strands made up of DNA and ____________________.
The protein helps the DNA stay together when chromosomes form
Chromosome - _____________________________ is passed from one
generation to the next on chromosomes. Before cell division, each
chromosome is duplicated, or copied.
Each chromosome consists of two identical ____________________________.
Each pair is attached at an area called the _________________________.
Mitosis
Occurs in body cells – somatic cells.
Forms two identical __________________________ - exactly like the original.
Divided into four phases:
1. ____________________
2. Metaphase
3. Anaphase
4. ____________________
Prophase
First and longest phase of mitosis
The ______________________ separate and take up positions on opposite
poles of the nucleus
___________________ become visible
Spindle Fibers appear
Nucleolus and ___________________________________ disappear
Metaphase
Chromosomes line up across the center of the cell (______________________)
_______________________ connect the centromere of each chromosome to
the poles of the spindle
Anaphase
The ______________________________ separate into individual
chromosomes and move in opposite directions
Chromosomes continue to move toward opposite poles of the cell
Telophase
Chromosomes gather at opposite ends of the cell and lose their distinct shape
A new _________________________________ forms around each cluster of
chromosomes
Chromatids unwind back into __________________________
New nucleus forms at each end of cells
Cytokinesis
Cytoplasm division
Cytoplasm pinches half, forming a _______________________________
Each daughter cell has an identical set of duplicate chromosomes