Download Life Cycle of Cells

Warm ups:
1. Do living things reproduce?
2. Can cells grow and reproduce?
Presenting…
The Cell Life
Cycle
Objective:
1. Explain the process of a
cell’s life cycle
2. Differentiate between
interphase, mitosis and
cytokinesis.
How do little elephants grow up to be BIG
elephants?
Life Cycle of Cells – 3 parts
1.
Interphase
2.
Mitosis
3.
Cytokinesis
1. Interphase - growth
a. The cell grows until it is ready to divide.
b. Chromosomes (DNA) and other cell parts
are copied
Interphase
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
2. Mitosis – division of the
nucleus
a. new cells have same
dna
b. happens in all body
cells and in many
single celled
organisms
c. Creates diploid cells
– 23 pairs of
chromosomes
NORMAL CELLS
http://www.cellsalive.com/mitosis.htm
Chromosomes
d. Chromosomes –
strands of tightly
wound DNA
e. Humans have 23
pairs of
chromosomes = 46
total chromosomes
(23 X 2 = 46)
Chromosomes are
paired up and
numbered.
Scientists then put
them in order from
biggest to smallest.
Last pair of are
called the sex
chromosomes.
XY will be male,
XX will be
female.
4 Parts of Mitosis
1. Prophase - nucleus disappears,
chromosomes start moving to middle of cell
2. Metaphase - chromosomes line up in middle
of cell (think M = metaphase/middle)
3. Anaphase - chromosomes are pulled
away/apart from their copies and move to
opposite sides of cell (think A =
anaphase/apart)
4. Telophase - nucleus membrane forms, cell
gets ready to divide (cytokinesis)
Prophase
Animal Cell
Plant Cell
Spindle fibers
Centrioles
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Metaphase
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Anaphase
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Telophase
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
FYI: Why is mitosis so
important?
• For growth, repair and replacement of cells
• Grow and Develop!
• Even after growth ends cell division is
important to make new cells to replace old
cells!
Did you know?
Billions of blood cells are replaced daily!
3. Cytokinesis: division of
cytoplasm
a. Animal cells - cell membrane pinches in.
b. Plant cells - a cell plate forms to divide
the cytoplasm.
20
Exit slip
Five finger summary: In the palm of your hand
that you have drawn on a piece of
paper….write “cell life cycle”. In each finger,
write “interphase”, “mitosis”, and “cytokinesis”
and write something about them. On your
other two fingers, pick a stage of mitosis and
explain what happens during that stage.
Cell life cycle