Ways that Cells divide.
Name:____________________________________Date:____________ Pd:________ group color:_________
Chromosome
This is an image of a chromosome. In Each human somatic body cell, there are 46 of these
in each cell, 2 of each size.
Replicated Chromosome: Sister Chromatids
This is a chromosome after DNA replication in the S phase of Interphase. Each side is
identical & is called a sister chromatid. This is still considered 1 chromosome.
In Each human somatic body cell, there are 46 of these in each cell, 2 of each size.
Mom
Dad
Homologous Chromosomes:
This represents a pair of homologous chromosomes. They are homologous because they
are the same size. Each X is has the genes for the same traits, but the versions of those
genes are different because one X is from mom and the other is from dad. For instance,
the X from your mother could have a gene for tongue rolling and the on from your Dad X
could have the gene for not being able to roll your tongue.
Homologous chromosomes only pair up in the first phases of meiosis.
The only pair that could be a different size is the sex chromosome. XX = girl, but XY=boy
and the Y is smaller (still shaped like an X though)
Somatic cell – body cells like your skin, liver, heart, stomach, kidney cells. These are diploid and have pairs of
chromosomes.
Gametes – sperm & egg. These are haploid and have 1 of each chromosome type.
Diploid – Cells that have 2 of each kind of chromosome (somatic cells)
Haploid- Cells that have only 1 of each kind of chromosome (sperm & egg)
The cell cycle: The process by which cells grow, copy all the DNA and cell contents, and then equal divides the contents
into 2 identical cells. Watch: http://goo.gl/X6zQ8I
G1, S, and G2 are called Interphase. Most of the time cells are in interphase. Only when a cell needs to replace a
damaged cell or if the organism is growing will M phase (mitosis) occur.
MITOSIS – MAKING SOMATIC CELLS- NUCLEAR DIVISION
This process clones your cells so that you can grow or replace old or damaged cells.
PMAT 2 identical diploid daughter cells
.
Mitosis
Nuclear Division:
Description
Cells for growth & repair of the body
Prophase, Metaphase, Anaphase,
Phases
Telophase/cytokinesis
What type of cell(s) produced somatic or
Somatic
gametes
Ex. liver, skin, bone, muscle cells
Number of cell produced
2
1
Number of divisions
Does crossing over occur?
Are daughter cells identical to the parent?
Are daughter cells identical to each other?
Do homologous chromosomes exist in
pairs?
no
yes
yes
no
BINARY FISSION
Organisms without a nucleus are called prokaryotes. Prokaryotes cannot undergo nuclear division; they reproduce by a
process called binary fission. It is similar to mitosis, but simpler.