Transcript CELLS, CELLS, & More CELLS!

CELLS, CELLS, & More CELLS!
The Cell Theory
• Cells are the fundamental building
blocks of life
• All living creatures are made up of cells
• Cells come from pre-existing cell
The adult human body is made up of about
60-90 trillion cells. (if you lined up all the
cells in a human body end-to-end, you
could actually circle the earth 4.5 times.)
Bone Cell
Brain Cell
Stomach Cell
Red Blood Cell
“TO HAVE OR NOT TO HAVE”
That is the question!
• PROKARYOTIC CELL
• Organisms whose
cells DO NOT have a
nucleus and
membrane bound
organelles
• EUKARYOTIC CELL
• Organisms whose
cells DO have a
nucleus &
membrane bound
organelles
Prokaryotic Cell (Bacterium cell)
Eukaryotic Cell (Animal Cell)
Why are cells so small?
Cells are small because……
• Diffusion of necessary materials is
quicker & more efficient when cells
have a large surface area/volume ratio
• Allows for continual renewal of cells
without interruption of entire organism
Conquering the GREAT DIVIDE
Cell Division
(Mitosis)
Why do organisms need new
cells?
• Cell damage/death
• Limited life span
• Cells get too large
to survive (SA:V ratio)
The Cell Cycle
• Each round of
growth & division in
a cell is a cell cycle
• G1-Cells grow
• S-Cell materials
doubles
• G2-final prep for
division
• Mitosis
The Stages of Mitosis
remember “IPMAT”
• Interphase-technically not a phase of
Mitosis but a stage of the Cell Cycle
• Prophase
• Metaphase
• Anaphase
• Telophase
Prophase
• Chromosomes in the
nucleus coil and
thicken
• The nucleolus
disappears
• Centrioles move to
opposite ends of cell
and spindle fibers
form
Metaphase
• Chromosomes line
up at the center of
the cell, this is
referred to as the
metaphase plate
• Spindle fibers are
attached to the
chromosomes at the
center called the
centromere
Anaphase
• Spindle fibers pull
apart the
chromosomes
• ½ of each
chromosome(now
called a chromatid)
moves to a new
daughter cell
Telophase
• Chromatids arrive at
opposite poles of cell
• Chromatids
DECONDENSE
• Cytokinesis begins-Cell
membrane begins to
pinch to form two new
identical daughter cells