Transcript Cell Division Vocabulary

Cell Division
Mitosis
Cell Division
Vocabulary
Mitosis- is the process in
which the nucleus divides to
form two identical nuclei.
 Chromosome- is a structure in
the nucleus that contains
hereditary material.
 Asexual Reproduction- a new
organism is produced from
ONE organism.

2
The Cell Cycle
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The regular sequence of growth and
division that cells undergo is known as
the cell cycle.
Steps:
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Cells grow & function, DNA copied, Cell
grows and prepares for mitosis, Mitosis
happens, and Cytoplasm divides.
The Phases
1.
2.
3.
4.
5.
6.
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Interphase

During interphase, the cell grows to its
mature size, makes a copy of its DNA,
and prepares to divide into two cells.
DNA is Replicated
(copied)
Next Stage is Mitosis: 4 Parts

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Prophase
Metaphase
Anaphase
Telophase
Prophase

Threadlike
chromatin in the
cell’s nucleus
begins to
condense and
coil.
Chromatin Condenses to Form
Chromosomes
The Chromosome
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Chromosome: “X” shaped
cell structure that directs cell
activities and passes on traits
to new cells.
Each identical strand of the
chromosome is called a
chromatid.
The strands are held together
by a structure called the
centromere.
Chromatin: Loosely coiled
DNA
Metaphase: Meet in the Middle
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Chromosomes line
up at the center of
the cell.
Each chromosome
attaches to a spindle
fiber at its
centromere.
METAPHASE!!!!!!
Anaphase: Split Apart

Chromosomes are
pulled apart by the
spindle fibers and
brought to each end
of the cell.
Telophase: Two New Nuclei
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Two new nuclei are formed
Chromosomes begin to uncoil
Cytokinesis

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Animal Cells: Cell membrane pinches in
between the two new cells.
Plant Cells: Cell plate forms between
the two cells. Cell Wall is too rigid to be
pinched apart.
Homework

Illustrate the Six stages of the Cell
Cycle. How you illustrate them or what
materials you use is completely up to
you. Just be sure that each stage is
clearly illustrated and labeled.
Length of the Cell Cycle of a
Human Liver Cell
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Interphase: 21 hours
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Growth : 9 hours
DNA Replication: 10 hours
Preparation for Division: 2 hours
Mitosis: 1 hour
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Prophase
Metaphase
Anaphase
Telophase
Sea Urchin Cell Cycle
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Sea Urchin Cell
Cycle takes 2 hours
Human Brain Cells
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Never divide, they remain in the first
part of interphase for as long as they
live!
Review
Cellular Asexual Reproduction
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Requires one organism to reproduce
Hereditary material will be IDENTICAL to the
parent.
Recall: Mitosis is the division of the nucleus.
Question: What if an organism doesn’t have a
nucleus?

Fission- an organism copies its genetic material
then divides into 2 identical organisms
Fission
Budding and regeneration

Budding- type of asexual reproduction
made possible because of cell division.

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The bud on the adult organism becomes
large enough it breaks away to live on it’s
own.
Regeneration- the process that uses cell
division to re-grow body parts.

Example: Starfish
Budding
The Steps of the Ladder
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Each rung of the DNA ladder is made
up of a pair of molecules called
nitrogen bases.
There are four kinds of Nitrogen
Bases:
1.
2.
3.
4.
Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)
The Pairs
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Adenine only pairs with Thymine
Guanine only pairs with Cytosine
DNA Replication
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The ladder
unzips and the
rungs find new
pairs that are
floating in the
nucleus.