Cell Cycle
Cell cycle- The sequence of
stages through which a cell
passes between one cell
division and the next. (The
cycle begin growth and
division. )
2
2
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The cell spends most of its time in
interphase.
Stage 1- G1- cell grows, organelles may
begin to duplicate, cytoplasm increases and
protein synthesis occurs
Stage 2- S- DNA replicates
Stage 3- G2-cell continues to grow,
organelles double, and microtubules
synthesize
 Mitosis
is a type of cell division
that generates two identical
daughter cells.
 Mitosis
 Body
cells.
occurs in body cells.
cells are called somatic



Mitosis is a part of the cell cycle. It
has 4 phases. (PMAT)
Human cells have 46 chromosomes or
23 pairs. This is called a diploid
number. (2N)
Mitosis requires only one parent asexual reproduction.
How do little elephants grow up to be BIG
elephants?
Skin cancer - the abnormal growth of
skin cells - most often develops on skin
exposed to the sun.
Cell that reproduce by asexual
reproduction reproduce constantly.
Animated Mitosis Cycle
http://www.cellsalive.com/mitosis.htm
• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase & Cytokinesis
Chromosomes are copied (# doubles)
• Chromosomes appear as threadlike coils
(chromatin) at the start, but each chromosome
and its copy(sister chromosome) change to sister
chromatids at end of this phase
•
Nucleus
CELL
MEMBRANE
Cytoplasm
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
•
•
Mitosis begins (cell begins to divide)
Centrioles (or poles) appear and begin to
move to opposite ends of the cell.
Spindle fibers form between the poles.
Centrioles
Sister chromatids
Spindle fibers
Animal Cell
Plant Cell
Spindle fibers
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Chromatids (or pairs of chromosomes) attach
to the spindle fibers.
Centrioles
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Chromatids (or pairs of chromosomes)
separate and begin to move to opposite
ends of the cell.
Centrioles
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
•
•
Two new nuclei form.
Chromosomes appear as chromatin (threads
rather than rods).
Mitosis ends.
Nuclei
Chromatin
Nuclei
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Cell membrane moves inward to create two
daughter cells – each with its own nucleus
with identical chromosomes.
Animal Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
Plant Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
24
1. What is a gene?
 2. What are chromosomes?
 3. Describe a prokaryotic
chromosome.
 4. Describe a eukaryotic
chromosome.
 5. What is chromatin?
 6. What is a chromatid?
 7. What is a centromere?

 1. Define Cell Cycle.
2. What is mitosis?
 3. What is cytokinesis?
 4. What is a spindle
fiber?
1.

 1. Define Cell Cycle.
2. What is mitosis?
 3. What is cytokinesis?
 4. What is a spindle
fiber?
1.
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
Chromatin – uncoiled
DNA + proteins (threads)

Chromosome – coiled
DNA + proteins (Looks
like an X)

Chromatid – only half of
a chromosome

Sister chromatids –
Two chromatids joined
together, by a centromere,
to form a chromosome
http://www.cellsalive.com/mitosis.htm