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Name:____________________ Date:____________________Hour:_____________
The cell cycle: interphase, mitosis, cytokinesis
Fill in the blank notes
The beginning of the cell cycle: Interphase
Interphase
1. Rapid _______________
 The cell grows
 ________________ production is high
2. ___________ synthesis and replication
 The cell copies its ___________________
 DNA synthesis does not occur all through ___________________ but is confined to
this specific time
3. ___________________ replicate: cell prepares for _______________
 Centrioles replicate
 ________________ and other ___________________ are manufactured and cell
parts needed for cell division are assembled
As interphase ends…Mitosis begins!
Mitosis
 Mitosis is the period of ______________ cell division in which two daughter cells
are formed, each containing a complete set of _______________
 Cells undergo mitosis (divides) as they approach the maximum cell
______________ at which the ________________ can provide blueprints for
________________ and the plasma membrane can efficiently transport
_____________ and __________________ into and out of the cell.
 It has 4 stages:
– _______________
– _______________
– _______________
– ________________
Prophase: the first stage
 This is the first and ________________ phase of mitosis.
 The long stringy chromatin ______________ up into visible
_________________.
 Each ___________________ chromosome is made up of
_____________ halves. The two halves of the doubled
structure are called ___________________________.
 The DNA of sister chromatids are exact ______________ of
each other and are formed when DNA is copied during
______________.
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 Sister chromatids are held together by a structure called a _________________.
 The centromere palys a role in chromosome ___________________ during
mitosis
 As prophase continues, the nucleus begins to _________________ as the nuclear
envelope ________________________.
 The centrioles begin to migrate to opposite _____________ of the cell
 Centrioles are made up of _______________ and are located just outside of the
nucleus.
 As the pairs of centrioles move to opposite ends of the cell and the
______________ begins to form between them.
 The spindle is a ______________-shaped ______________like structure made of
thin fibers of _________________.
 Spindle fibers play a vital role in the _______________ of sister chromatids.
Metaphase: the second stage of mitosis
 The doubled chromosomes become
_______________ to the
___________________ fibers by their
____________________.
 The chromosomes are pulled by the
spindle fibers and begin to line up on the
________________, or equator, of the
spindle.
 Each sister chromatid is attached to its
__________ spindle fiber.
 One sister chromatid’s spindle fiber
extends to one ___________, and the other extends to the _________________
pole.
 This arrangement is important because it ensures that each new cell receives an
___________________ and _________________ set of chromosomes
Anaphase: the third stage of mitosis
 Sister chromatids begin to ___________________.
 The centromers _______________ apart and chromatid
pairs ________________ from each other.
 The chromatids are pulled apart by the ________________
of the microtubules in the spindle fibers.
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Telophase: the fourth & final phase of mitosis
 Telophase begins as the _______________ reach
the opposite poles of the cell.
 The chromosomes ________________ so they can
begin to direct the __________________ activities
of the new cells.
 The spindle begins to _________________ down.
 The nuclear envelope begins to ____________________
 A new double __________________ begins to form between the two new nuclei.
The end of Mitosis… The beginning of cytokinesis.
 Cytokinesis – the division of the cells cytoplasm
 Cytokinesis is different in animals and plants
 Cytokinesis in animals:
– The plasma membrane pinches in along the equator and the two cells are
seperated.
 Cytokinesis in Plants:
– Plant cells have a rigid cell wall so the plasma membrane does not pinch
in.
– A structure called the cell plate is laid down across the cell’s equator.
– A cell membrane forms around each cell and new cell walls form on each
side of the cell plate until separation is complete.
The new cells begin interphase! The cycle starts
over again…
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