Transcript Mitosis and Meiosis

Mitosis
and
Meiosis
The Cell Cycle
• DNA: contains the
information that tells a cell
how to make proteins.
• Chromosomes: coiled
structure of DNA and protein
that forms in the cell
nucleus during cell division.
Prokaryotic Cells
• Binary Fission: the simple cell
division in which one cell splits
into two; used by bacteria.
•Homologous chromosomes:
chromosomes with matching
information.
•Chromotids: identical copies of a
chromosome.
•Centromere: The region that holds
chromotids together when a
chromosome is duplicated.
MITOSIS
• Nuclear division in a
eukaryotic cell in which
each cell receives a
copy of the original
chromosomes.
Remember…….
• There are 3 STAGES in this
process
• Interphase
• Mitosis
• Cytokinesis
Four phases of Mitosis
Prophase
Metaphase
Anaphase
Telophase
Interphase
•The time in
between
cell
division
Interphase
• THE CELL GROWS TO ITS MATURE
SIZE
• THE CELL MAKES A COPY OF ITS DNA
CHROMATIN-(threadlike form of dna)
• IT PREPARES TO DIVIDE
Prophase
• Nuclear membrane
(phase 1)
breaks apart
• Chromosomes
become rodlike.
• Centrioles move to
opposite sides of cell.
• Fibers form between
two pairs of
centrioles
Metaphase
(phase 2)
• Chromosomes line
up along equator
(middle) of the cell.
• Spindle fibers
attach through the
centromere
Anaphase
(phase 3)
• Chromotids separate and
are pulled to opposite side
of cell by the fibers attached
to centrioles
Telophase
(phase 4)
• Nuclear membrane forms
around two sets of
chromosomes.
• Fibers disappear
Cytokinesis
• Cytoplasm
splits in two.
• Result: two
identical cell