Download Mitosis

Name: ______________________________
Mitosis
Mitosis is a type of division that produces a __________ of a cell. This kind of
cell division is necessary to replace your skin if you have a wound – or just to replace the
over 100 billion skin cells you lose every day!
Mitosis is also the type of division that takes place in _________________
_________________. (Bacteria and amoebas are examples of two organisms that
reproduce asexually.) Asexual reproduction makes copies of the original – kind of like
a copy machine.
Parent Cell The starting point in the reproduction of a cell. The chromatin, _________
_____________, are a tangled mess of hair-like fibers inside the nuclear
membrane.
Prophase
The chromatin bunch up and form an X and are now called chromosomes.
In the cytoplasm, structures called spindle fibers form to guide the
chromosomes to the opposite ends of the cell. The nuclear membrane
(surrounds the nucleus) breaks down and releases the chromosomes into the
___________________ in the cell.
Metaphase The chromosomes line-up in the ______________ of the cell and each
chromosome attaches to a spindle fiber.
Anaphase
The chromosomes split in half – making chromatids – which then move
____________ from each other along the spindle fibers toward opposite
ends of the cell. Notice the similarities in words – chromatin and
chromatids – but also notice the different definitions.
Telophase
The cell membrane pinches together to meet in the middle and forms _____
_____________ ________. During this process the nuclear membrane
reforms, spindle fibers are absorbed into the cytoplasm, and chromatids
unravel back into a tangled mess. The two cells that we end up with are
called Daughter Cells. They become the new Parent Cells.
Results of mitosis:
1.
2.
Purposes of mitosis:
1.
2.
Name: ______________________________
Meiosis
Meiosis is a type of cell division where cells divide in half __________. This is
the kind of cell division that takes place to produce gametes, sex cells like __________
and _________. Meiosis is the type of division that takes place so sexual reproduction
is possible. The cells that are produced because of meiosis are what combine to
ultimately produce an offspring. Sexual reproduction produces a wide variety of end
results – a lot of ____________. Just look at all the different people around you!
Parent Cell The beginning stage in the reproduction of a cell. The chromatin, genetic
material, are a tangled mess of hair-like fibers inside the _______________
__________________.
Prophase 1 The chromatin __________ ______ and form an X and are now called
chromosomes. In the cytoplasm, structures called spindle fibers form to
guide the chromosomes to the opposite ends of the cell. The nuclear
membrane (surrounds the nucleus) breaks down and releases the
chromosomes into the cytoplasm in the cell.
Metaphase 1 The chromosomes line up in the middle of the cell and each ____________
attaches to a spindle fiber.
Anaphase 1 Half of the chromosomes move along the ___________ ___________ away
from each other toward each end of the cell.
Telophase 1 The ________ ________________ pinches together to meet in the middle
and forms two daughter cells. During this process the nuclear membrane
reforms, spindle fibers are absorbed into the cytoplasm and chromatids
unravel back into a tangled mess.
Prophase 2 In the cytoplasm, structures called ___________ ____________ form to
guide the chromosomes to the opposite ends of the cell. The nuclear
membrane breaks down and releases the chromosomes into the cytoplasm in
the cell.
Metaphase 2 The chromosomes line up in the middle of the cell and each _____________
attaches to a spindle fiber.
Anaphase 2 The chromosomes __________ in half – making chromatids – which then
move along the spindle fibers away from each other toward opposite ends of
the cell.
Name: ______________________________
Telophase 2 The cell membrane pinches together to meet in the middle and forms two
daughter cells from each of the originals – giving us a total of ___________
daughter cells. During this process the nuclear membrane reforms, spindle
fibers are absorbed into the cytoplasm and chromatids unravel back into a
tangled mess.
Results of meiosis:
1.
2.
Purposes of meiosis:
1.
2.
Asexual reproduction: production of an offspring genetically identical to the parent;
only one organism is necessary for this to occur
Chromatid: one-half of a chromosome
Chromatin: nucleic acids and proteins that bunch up to form chromosomes; genetic
material
Chromosome: contains the genetic material of the organism
Daughter Cells: the cells that are made by cell division
Gamete: sex cell
Nuclear membrane: the outer boundary of the nucleus (similar to the cell membrane)
Offspring: the organism created by either asexual or sexual reproduction
Parent Cell: the cell before cell division begins
Sexual reproduction: production of a genetically unique individual by joining two sex
cells (like a sperm and an egg combining)
Spindle fibers: objects that form at both ends of a cell in the cytoplasm that indicate
which way the chromosomes will split during cell division