Download Process of Cell Division

Process of Cell
Division
Chromosomes
Chromosomes:
Packages of
bundled DNA
Chromosomes allow cells to
handle such a large molecule
like DNA
Prokaryotic Chromosomes
Most
prokaryotes contain a single,
circular DNA chromosome within
their cytoplasm.
Eukaryotic Chromosomes
 Eukaryotic
cells generally have more DNA
than prokaryotes, therefore contain
more chromosomes
Ex:
Fruit flies have 8 and Humans have 46
 Chromosomes
make it possible to
separate DNA precisely during cell
division
Eukaryotic Chromosomes
The Cell Cycle
Cell Cycle: series of events as a cell
grows and divides


Cell grows, prepares for division, and
divides to form two daughter cells
Prokaryotic Cell Cycle
DNA
is replicated once the cell
reaches a certain size
Binary fission
Once
chromosome is copied,
each copy attaches to a
different part of the cell
membrane
Fibers form between
chromosomes
Cell is pinched and two new
cells are formed
Eukaryotic Cell Cycle
Interphase
G1
Phase- Cell Growth: cells
increase in size and make new
proteins and organelles
G
stands for gap
Eukaryotic Cell Cycle
Interphase
S
Phase- DNA Replication: New DNA
is made. At the end of the S phase,
the cell will have twice as much DNA
as it started with
S
stands for synthesis
Ex: 46 chromosomes doubles to 92
Eukaryotic Cell Cycle
Interphase
G2
Phase- many of the
organelles and molecules
required for cell division are
produced
Shortest
phase
Eukaryotic Cell Cycle
Mitosis:
division of the cell nucleus
Prophase:
genetic material inside
nucleus condenses and the duplicated
chromosomes become visible. Outside
the nucleus, the spindle starts to form
Centromere: area where DNA
molecules are attached
Sister Chromatids: identical
chromosomes
Centrioles: organelle that creates
spindle fibers
Eukaryotic Cell Cycle
Mitosis
Metaphase:
the
centromeres of the
duplicated chromosomes
line up across the center
of the cell. Spindle fibers
connect the centromere of
each chromosome to the
two poles of the spindle.
Think
of meta and middle
Eukaryotic Cell Cycle
Mitosis
Anaphase:
the
chromosomes
separate and move
along spindle fibers
to opposite ends of
the cell
Eukaryotic Cell Cycle
Mitosis
Telophase:
the
chromosomes, which
were distinct and
condensed, begin to
spread out into a
tangle of chromatin.
This
is the last phase
of mitosis and there is
still only one cell
Eukaryotic Cell Cycle
Cytokinesis
Animal
cells: cell membrane is
drawn inward until the cytoplasm is
pinched into two nearly equal parts
Plant cells: cell plate forms forms
halfway between divided nuclei
Prophase
Interphase
Metaphase
Anaphase
Telophase/Cytokinesis