Cell Division Notes
Name:
Chapters 10, 11.4
Date:
Period:
Activating Prior Knowledge:
1. List the eight characteristics of living things.
2. List four differences between plant and animal cells.
3. Which animal organelle is used in cell division?
4. Which organelle surrounds the cell membrane in plant cells?
5. What are chromosomes made of?
6. How many chromosomes are found in each human body cell?
7. Can you name five types/kinds of cells found in the human body?
8. Where did YOUR chromosomes come from?
9. Where are chromosomes found in your cell (organelle)?
10. What do we call the jelly-like material within the cell?
11. Name three differences between prokaryotic and eukaryotic cells.
1
Vocabulary:
1. Cell Division
2. Asexual reproduction
3. Sexual Reproduction
4. Cell Cycle
5. Chromosome
6. Histone
7. Nucleosome
8. Chromatin
9. Mitosis
10. Cytokinesis
11. Prophase
12. Centromere
13. Chromatid
14. Centriole
15. Metaphase
16. Anaphase
17. Telophase
18. Meiosis
19. Homologous chromosomes
20. Diploid
21. Haploid
22. Synapsis
23. Tetrad
24. Crossing Over
25. Independent Assortment
26. Zygote
2
Limits to Cell Size
Information “Overload” and Exchanging Materials:
There are two main reasons why cells do not grow indefinitely:
1.
2.

Function of the cell membrane:

The rate at which this exchange takes place depends on the ____________ _________ of a cell.

The rate at which
and
are used up and
are produced depends on the cell’s ____________________.

The ratio of
to
is key to
understanding why cells must divide as they grow.

As the length of the sides of a cube increases,

If a cell gets too
, the
enough to get enough
of the cell is not large
and
in and
out.
Division of the Cell:

Before a cell grows too large, it
into two new “daughter” cells in a process called
________ ______________________.

Before cell division, the cell copies all of its _________.

It then divides into two “__________________” cells. Each daughter cell receives a complete set of

Cell division reduces cell________________. It also results in an increased
___________________________________________________, for each daughter cell.
3
Cell Division and Reproduction
Type
Asexual
Sexual
Number of
Parent(s)
Outcome
Genetically
offspring
Genetically
offspring
Prokaryotic and eukaryotic _______________
Example(s)
celled organisms and many
Most _______________ and _____________,
___________________________ cellular
many __________________ celled organisms
organisms
Advantages
Chromosomes:
 Every cell must
its genetic information before
 Each
begins.
cell gets its own copy of that genetic information.
 Cells of every organism have a
Prokaryotic Chromosomes
 Prokaryotic cells lack
the
. Instead, their
are found in
.
 Most prokaryotes contain a
DNA
molecule, or chromosome, that contains most of the cell’s genetic information.
Eukaryotic Chromosomes
 In eukaryotic cells, chromosomes are located in the
, and are made up of
.
 Chromatin is composed of
and
.
 DNA coils around histone proteins to form
.
 The nucleosomes interact with one another to form
.
4
The Prokaryotic Cell Cycle:

________________ ___________________ is a form of
reproduction during which two genetically ___________________ cells are
produced.

For example,
reproduce by binary fission.
The Eukaryotic Cell Cycle:
Consists of
phases:




Interphase:
G1 Phase
S Phase
G2 Phase
M Phase: Cell Division
Mitosis
Cytokinesis
5
Important cell structures involved in MITOSIS:
 Chromatid –
 Centromere –
 Centrioles –
 Spindle –
Mitosis
Phase
Description

Illustration
The ______________ phase of mitosis, the duplicated
chromosome _________________ and becomes
_______________________.

Prophase
The centrioles move ___________________________
____________________________________________

The spindle forms and DNA strands attach at a point
called their ______________________________.

The ________________________ disappears and the
nuclear envelope _____________________________.
 This is the _____________________ stage of mitosis.

During metaphase, the ___________ phase of mitosis,
the centromeres of the duplicated chromosomes
___________________________________________.
Metaphase  The ______________________ connect the centromere
of each chromosome to the ______ poles of the
___________________.
 This is the ___________________ phase of mitosis.

During anaphase, the _______ phase of mitosis, the
centromeres are _______________ and the
chromatids _______________ to become
Anaphase
_________________ chromosomes.

The chromosomes separate into two groups near the
_________________________________.
6

During telophase, the ___________ and ___________
phase of mitosis, the chromosomes _______________
__________________________________________

A nuclear envelope ______________ around each
________________ of chromosomes.
Telophase

The spindle ________________, and a
___________________ becomes visible in each
___________________ nucleus.

Chromosomes __________________.
Cytokinesis
Animal Cells
Plant Cells
7
Chromosome Number
 Chromosomes -
- are the carriers of genes.
 The genes are located in
on chromosomes.
Homologous Chromosomes
 A body cell in an adult fruit fly has
chromosomes.
 Four of the chromosomes come from its
parent, and four come from its
 These two sets of chromosomes are
parent.
, meaning that
Diploid Cells
 A cell that contains
sets of homologous chromosomes is
meaning “
,
.”
 The diploid number of chromosomes is sometimes represented by the symbol
 For the fruit fly, the diploid number is
, which can be written as 2N =
.
, where N represents
Haploid Cells
 Some cells contain only a
set of
set of chromosomes, and therefore a
.
, meaning “
 Such cells are
 The
.”
of sexually reproducing organisms are haploid.
 For fruit fly gametes, the haploid number is
, which can be written as N =
.
Zygote =
 Haploid
+ Haploid
=
Synapsis and Tetrads
 During
, the
chromosomes
, forming a structure called a
contains
, which
.
Crossing Over
 As homologous chromosomes pair up and form tetrads, they undergo a process called crossing-over.
 Chromatids of the
chromosomes
 The crossed sections of the chromatids are
one another.
.
 Crossing-over is important because it produces new combinations of
in the cell.
Independent Assortment
 Genes for different traits can
independently during the formation of
.
8
Phases of Meiosis
 Meiosis is a process in which the number of
through the separation of
 Meiosis usually involves
per cell is cut in
chromosomes in a
distinct divisions, called
 By the end of meiosis II, the diploid cell becomes
cell.
and
cells.
Meiosis I
Phase
Description
Illustration
Interphase
Prophase I
 The cells begin to
, and the chromosomes
__________ _____, forming a structure called a
_________________, which contains _____ chromatids.
 As homologous chromosomes pair up and form tetrads,
they undergo a process called
_____________________________________.
 Paired ___________________ chromosomes line up
Metaphase I
across the __________________ of the cell.
 Spindle fibers pull each homologous chromosome
Anaphase I
_________ toward ______________ ends of the cell.
 When anaphase I is complete, the __________________
_________________________________________________
 A __________________________________ forms
Telophase I
around each cluster of ___________________________.
 Cytokinesis follows ______________________, forming
Cytokinesis
_________ new cells.
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NOTE:
 Meiosis I results in ___________ cells, called _________________ cells.
 Because each pair of homologous chromosomes was separated, neither daughter cell has _____________
____________________________________________________________________________________.
 The two cells produced by meiosis I have sets of chromosomes and alleles _________________________
____________________________________________________________________________________.
Meiosis II
 The ________ cells produced by meiosis I now enter a ______________ meiotic division.
 Unlike the first division, neither cell goes through a round of
entering meiosis II.
Phase
Prophase II
Description
 As the cells enter prophase II, their chromosomes each consisting of ______________________ become ______________________.
 The chromosomes do not pair to form
________________, because the homologous
pairs were already separated during meiosis I.
before
Illustration
 ________________________ line up in the
Metaphase II
____________________ of each cell.
 The paired ___________________________
Anaphase II
_________________________________.
 The ________________________ reforms around
the ____________________.
Telophase II
 Each of the _____ daughter cells produced in
__________________ receives _______
chromatids (in this example).
 These ______ daughter cells now contain the
Cytokinesis
_______________ number (N) - just _______
chromosomes each.
10
Gamete Formation:
Process
Spermatogenesis
Oogenesis
Description
and
Illustration
11
Comparing Mitosis and Meiosis:
Mitosis
Meiosis
Genetically identical daughter cells
Produces gametes
Metaphase
Produces two cells
Crossing over
Polar bodies
Telophase
Produces diploid cells
Anaphase
Sperm
Produces haploid cells
Egg
Skin cells
Tetrads
Prophase
Produces four daughter cells
Mitosis
Meiosis
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