Download Chapter10. The Cell Growth and Division

Teaching plan of Cell Biology
Chapter10. The Cell Growth and
Division
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Teaching plan of Cell Biology
Lesson plans
roll number：_______10________
Course Title
Medical Cell
Biology
Major
clinic
Teacher
Xiamixinuer.Yilike
Plan hours
4 hours
Professional
Title
Name of the
Lecture
Teaching
Purposes
and
Requiremen
t
Class
Professional level
Biology Professor
The time of
writing
Chapter 10: Cell Growth and Division
Using time
undergraduate
course
Teaching Purposes: To learn the steps of the cell cycle, cell division controls and the
mechanics of cell division.
Teaching Requirements:
1. Mastering: concept of cell cycle, mitosis and meiosis; main features of mitosis
prophase, metaphase, anaphase and telophase; characteristics of the stages in meiosis;
comparison between mitosis and meiosis.
2. Comprehending: characteristics of the stages of the cell cycle; biological significance
of mitosis and meiosis.
Important points ： concept of cell cycle,process of mitosis , characteristics of the
Important stages in meiosis
and Difficult
points
Difficult points: feutures of all stage of cell cycle and prophase Ⅰmeiosis.
Update
teaching
content
Teaching
methods
and
organization
al
Teaching
tools
Textbook
and
reference
books
Add animation to demonstrate the movement of mitosis and meiosis process.new cases
increased.
Teaching methods ： Multimedia lectures given . Heuristic teaching methods will be
used.
organizational arrangements ：cell cyle and mitosis 2 hours,meiosis and comparition
will be teach 2 hours,
multiedia will be used.
text book ：Cell Biology , China Medical University（6th edition）
Reference ：1.Essential Cell Biology.Bruce Albert’s；2.Cell and Molecular Biology，
Gerald Karp；3. Molecular Biology Disc；4. Lysosomes in biology and pathology J. T.
Dingle5.The cytoskeleton: an introductory survey/ Q28/C74,M. Schliwa;6.Essentials of
cell biology/2d ed. Q28/C71=2,Dyson, Robert D. Allyn and Bacon.
collective
preparation Mainly Teach the concepts of the cell cycle , mitosis and meiosis.
of
Opinion of
Agreed to carry out prepared the lessons plan. Give attention to use appopirate teaching
the
signature of the dean：
methods .
department
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Teaching plan of Cell Biology
Test for Nucleus(Print the page let students do it before the class in 1015min)
Name
Roll No
Marks_________
1. The nucleus structure: ___________nuclear envelope surrounds the nucleusThe
nuclear envelope consists of two membranes by a___________.
3. ___________ of the nuclear envelope is lined by the nuclear lamina
4. ___________ supports the nuclear envelope: Gives shape and stability of nuclear
envelope.
5. ___________provides a structure link between chromatin and nuclear envelope.
6. The nuclear lamina is composed of ___________.
7. The nuclear lamina is one kind of ___________.
8. If all phosphate groups are removed, a nucleotide
becomes___________.nucleoside
9. The integrity of the nuclear lamina is regulated by ___________and ___________.
10. Molecules can enter and exit the nucleus through ___________.
11. Transport of large proteins into nucleus needs ___________and ___________ is
required.
12. ___________ exist in different states throughout the life of a cell. ___________:
(Interphase) Dispersed through the nucleus.
13. ___________ is the basic unit of chromatin structure
14. ___________contains a nuclear lamina involved in structural support.
15. A histone ___________ forms the nucleosome core
16. The nuclear envelope contains an outer membrane continuous with the
__________.
17. ___________site of 45S rRNA processing.
18. ___________is the most abundant proteins associated with eukaryotic DNA; rich
in positively charged basic amino acids, which interact with the negatively
charged phosphate groups in DNA;
19. The chromatins which are light-staining, less condensed and have transcriptional
activities are ___________.
20. The chromatins which are dark-staining condensed and no transcriptional
activities are ___________.
21. Heterochromatin can be divided into two classes: ___________ and ___________.
22. Nucleolus Structure includes: _____________________;
_______________________;
______________________.
23. Functions of nucleolus: ___________.
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Teaching plan of Cell Biology
24. ___________ is non membrane-bounded structures present in the nucleus.
25. ___________site of synthesis of histone mRNA
26. __________site of transcriptionally inactive DNA
27. ___________site of transcription by RNA polymerase II
28. In humans, the Barr body is ___________ X chromosome in females
29. The DNA of nucleoli encodes the cells __________ genes
30. Chemical component of chromatin are. ___________ ,
___________,___________ and___________.
31. __________preventing the replication and transcription of DNA
32. Describe briefly the difference between euchromatin and heterochromatin.
33. Describe briefly structure of nucleosome?
Chapter 10 The Cell Growth and Division
Teaching Purposes: To learn the steps of the cell cycle, cell division controls and the
mechanics of cell division.
Teaching Requirements:
1. Mastering: concept of cell cycle, mitosis and meiosis; main features of mitosis
prophase, metaphase, anaphase and telophase; characteristics of the stages in meiosis;
comparison between mitosis and meiosis.
2. Comprehending: characteristics of the stages of the cell cycle; biological
significance of mitosis and meiosis.
3. Understanding: relationship between the cell cycle and the study of medicine.
Teaching Outline:
1. The cell cycle
2. Mitosis
3. Cytokinesis
4. Meiosis
5. The cell-cycle control system
Textbook
<Cell Biology> Abridgen by department of Cell Biology China Medical
University,sixth edition,2000.
Reference
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Teaching plan of Cell Biology
(1) Arberts, B. et al. Molecular Biology of the Cell, Garland Publishing, Inc.
2002, 2004, 2008.
(2) Arberts, B. et al. Essential Cell Biology, An Introduction to the Molecular
Biology of the cell, Garland Publishing, Inc. 1997, 2004.
(3) Karp, G. Cell and Molecular Biology--Concepts and Experiments, John &
Whley Sons, Inc. 2002, 2005, 2007.
(4) Lodish H. et al. Molecular Cell Biology, W.H.Freeman, Inc. 1999, 2007.
(5) Becker W.M. The World of the Cell, The Benjamin/Cummings Publishing
Company. 2000 .
(6) Kleinsmith L.J and Kish V.M. Principles of Cell and Molecular Biology,
Harper Collins College Publishers. 1995.
attention： master point※※※；comprehending point※※；understand※
General Statement of The cell cycle
Significance of the Cell proliferation and its regulation
a. for the growth and development of a multicellular organism, and for the
generation of offspring;
b. Produce new organisms in unicellular species;
c. Renew the aging, apoptotic cells, and damaged tissue;
A.Definition of the cell cycle: The cell cycle is the process by which a cell grows,
duplicates its DNA, and divides into identical daughter cells.
The cell cycle is divided into
two main parts: interphase and
mitosis . Interphase is
subdivided into three phases:
gap phase 1 (G1), synthesis (S),
and gap phase 2 (G2). Different
phases have different time named cellular cycle timing .TG1 means G1 Timing.
Cells divides into 3
categories of: Cycling cells
(Dividing continuously,
constantly—Stem cells, skin
cells, embryonic cells; G0
cells (Do not divide normally, cell never divides in adult; out of cell cycle in Go
but divide when given an appropriate stimulus: liver cells, lymphocytes) and
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Teaching plan of Cell Biology
Terminal cells (Highly specialized, have lost the ability to divide until they die;
muscle cells, red blood cells, nerve cells)
A.Cell Cycle
Interphase - the phase of a cell's life cycle in which DNA and histon are replicated.
includes:
G1 phase:Gap phase 1 begins at the completion of mitosis and cytokinesis and
lasts until the beginning of S phase. This phase is generally the longest of the
four cell cycle phases and is quite variable in length. During this phase, the cell
chooses either to replicate its deoxyribonucleic acid (DNA) or to exit the cell
cycle and enter a quiescent state (the G0 phase).
S phase:Replication of the chromosomes is restricted to one specific portion of
interphase, called S phase (DNA synthesis phase), which typically lasts about 6
h. In mammalian cells, the start of S phase—the actual initiation of DNA
synthesis—takes place several hours after the cell has committed to carrying
out DNA synthesis. During S phase, each chromosome replicates exactly once
to form a pair of physically linked sister chromatids. In animal cells, a pair of
centrioles is also duplicated during S phase. See also Chromosome; Genetics.
G2 phase:The portion of interphase that follows S phase is called gap phase 2.
Some cells can exit the cell cycle from G2 phase, just as they can from G1
phase.
M phase：M phase includes the over lapping
processes of mitosis and cytokinesis. Mitosis is divided
into five stages: prophase, prometaphase, metaphase,
anaphase, and telophase. Cytokinesis usually begins
during
anaphase and
ends at a point
after the
completion of mitosis. At the end of
cytokinesis, the parent cell has formed
its two G1 phase progeny and the cell is
ready to repeat the cycle. See also
Cytokinesis; Mitosis
B.Mitosis
Prophase –
1.
the nuclear envelope dissolves and
nucleolus disappear,(see picture below)
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Teaching plan of Cell Biology
1. the phase of mitosis in which the
duplicated chromosomes condense,
2. centrioles divide and move to opposite ends of the cell.
Centrosome duplicated at S, and separate to form mitotic spindle at the
beginning of prophase（see picture above）
3. Spindle
formed
Schematic representation of the kinetochore
Metaphase - the phase of mitosis in which the
chromosomes line up at the equator (the central plane)
Golgi, ER reconstruct of the cell.
The pushing and pulling forces drive the
chromosomes to the metaphase plate
MT behavior during formation of the metaphase
plate. Initially,MT from
opposite poles are different
in length(see picture left)
Anaphase - the phase of
mitosis in which the
chromosomes begin to
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Teaching plan of Cell Biology
separate. The events of Anaphase: Both anaphase A and anaphase B contribute to the
movement of chromosome toward the spindle poles
Anaphase A: The movement of the chromosomes toward the poles;
Kinetochore MT disaassenble at both ends during anaphase A.
Anaphase B: The two spindle poles move farther apart. Both pushing and
pulling forces contribute to anaphase B
A model explains the chromosome movement in anaphase
Telophase - the last phase of mitosis, when the chromosomes migrate to opposite
ends of the cell, two new nuclear envelopes and Nucleolus reassemble, and the
chromosomes uncoil to chromatin.
1.Chromosome uncondense
2.Nuclear envelope reforms around individual
chromosome
3.Nucleolus reassemble
Cytokinesis:In animal cells The MT of mitotic
spindle determine the plane of animal cell division; Mitosis can occur without
cytokinesis.
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Teaching plan of Cell Biology
Contractile ring: Actin and myosinII in the contractile ring generate the force
for cytokinesis
C.Meiosis: reduces the number of chromosomes by half.Daughter cells differ
from parent, and each other. The first cycle includes: the first interphase ,The
first division, The second cycle includes: the second interphase (short) The
second division.Meiosis involves two divisions; both divide into prophase,
metaphase, anaphase and telophase.
First division of meiosis :Prophase 1: Prophase futher divides into 5 subphases:
Each chromosome dupicates and remains closely associated. These are called
sister chromatids. Crossing-over can occur during the latter part of this stage.
Metaphase 1: Homologous chromosomes align at the equatorial plate.
Anaphase 1: Homologous pairs separate with sister chromatids remaining
together.
Telophase 1: Two daughter cells are formed with each daughter containing only
one chromosome of the homologous pair.
Let’s study of 5 subphases of prophase 1
Leptotene: The chromosomes strands are very elongated,thin,visible single
strands,we call it “slender stage” too.The visible small dark granules are called
CHROMOMERES.
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Teaching plan of Cell Biology
Zygotene: Homologous chromosomes pairs off in zipper
fashion,starting at various points along this line,we call
the phenomenon SYNAPSIS.The chromosome pairs is
called BIVALENTS
Meiotic chromosome pairing culminates in the
formation of the
synaptonemal
complex.
Pachytene: Chromosomes continue to shorten during this
stage,each synapsis figure has four strands called
TETRADS.Two closely related non-sister chromatids
changed one or several parts by breaking and rejoining.We
called it CROSSING OVER.
The picture right is the comparison of the mechanisms of chromosome
alignment (at metaphase) and separation (at anaphase) in meiotic division I and
meiotic division II.
The picture showns the two major contributions
to the reassortment of genetic material that
occurs in the production of gametes during
meiosis.
Diplotene: The stage also lenown as “doubled
thread”.tetrads can be observed
microscopically,the doubled homologous repel
each other.The points where crossing over had
occurred between non-sister chromatids are
called CHIASMATA.
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Teaching plan of Cell Biology
Diakinesis: Chromosomes shorten and thicken.The CHIASMATA moves
toward the end of the chromatids at the same time homologous pairs continue to
repel further.So we can see the shape like number “8”, “o” or “+”
Meiosis II:Second division of meiosis: Gamete formation divides to
1. Prophase 2: DNA does not replicate.
2. Metaphase 2: Chromosomes align at the equatorial plate.
3. Anaphase 2: Centromeres divide and sister chromatids migrate separately to
each pole.
4. Telophase 2: Cell division is complete. Four haploid daughter cells are
obtained.
Fertilization between haploid gametes results in a third source of genetic
recombination because there is the combining of chromosomes from different
individuals (parents).
The three source of genetic recombination are:
1.Independent alignment of paired chromosomes along the metaphase I plate; 2.
Crossing-over during prophase I; 3. Combining of chromosomes of genetically
different gametes
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Teaching plan of Cell Biology
There are 6 major take home lessons from the story of MEIOSIS.
Let me summarize the major features:
1.Chromosomes duplicate only at INTERPHASEⅠ, not at INTERPHASEⅡ.
2.SYNAPSIS is the process that brings the homologous strands into intimate
contact.
3.These homologous strands then CROSS OVER and RECOMBINE.
4.The four stranded BIVALENTS are separated by the two ANAPHASES.
During ANAPHASESⅠ, the homologous chromosomes separate. During
ANAPHASEⅡ , the sister chromosomes separate.
5.The four cell that result from the two division process carry only half the
number of chromosomes from the original cell.
6.MEIOSIS is where increasing variation in the offspring take place such as:
← cross over
↑ random line up of chromosomes at METAPHASEⅠ so that
paternal and maternal chromosomes are mixed by the time a cell enters
MEIOSISⅡ
→ random selection of cells with polar bodies to be the egg
cells take place.
Comparison of Meiosis with Mitosis
Before mitosis and meiosis, DNA replication
occurs only once during the interphase prior
to cell division.
Mitosis requires one division, and Meiosis
requires two divisions.
Two diploid daughter cells result from mitosis,
and four haploid daughter cells result from
meiosis.
Daughter cells from mitosis are genetically
identical
to parental cells
Daughter cells from meiosis are not genetically identical to parental cells.
Mitosis occurs in all somatic cells for growth and
repair.
Meiosis occurs only in the reproductive organs for
the production of gametes.
Comparison of Meiosis I to Mitosis
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Teaching plan of Cell Biology
Meiosis I:
Prophase I - pairing of homologous chromosomes
Metaphase I – homologous pairs line up at metaphase plate
Anaphase I – homologous chromosomes separate
Telophase I – daughter cells are haploid
Mitosis:
Prophase has no such pairing
Metaphase – chromosomes align at metaphase plate
Anaphase – sister chromatids separate
Telophase – diploid cells
Comparison of Meiosis II to Mitosis
The events of meiosis II are like those of mitosis except in meiosis II, the nuclei
contain the haploid number of chromosomes.
At the end of telophase II of meiosis II, there are four haploid daughter cells that
are not genetically identical.
At the end of mitosis, there are two diploid daughter cells that are identical.
The human life cycle requires both mitosis and meiosis.
In males, meiosis occurs as spermatogenesis and produces sperm.
In females, meiosis occurs as
oogenesis and produces egg cells.
Mitosis is involved in the growth of a
child and repair of tissues during
life.
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Teaching plan of Cell Biology
Homework
1. What happens as homologous chromosomes pair up during prophase I of
meiosis?
2. How does metaphase of mitosis differ from metaphase I of meiosis?
3. What is the sole purpose of meiosis?
4.What specific activities, involving DNA, occur during interphase prior to both
mitosis and meiosis?
Any Questions??
Summary of the chapter 13
1.
Significance of the Cell proliferation and its regulation
2.
Definition of the cell cycle:
3.
The cell cycle is divided into haw many phases? Each phases includes haw many
small phases?
4.
Cells divides into haw many categories? What are they and make example ?
5.
6.
Mitosis includes haw many phases ? What are the futures of each phases?
Prophase futher divides into haw many subphases? What are the futures of each
subphases?
7.
What are the 6 major take home lessons from the story of MEIOSIS?
8.
Compare of Meiosis with Mitosis
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Teaching plan of Cell Biology
Reference of Major Journals
Cell
Nature
Science
EMBO
Annual Review of Cell Biology
Trends in Cell Biology
Cell Research
Biology Website
http://www.ebiotrade.com/
http://www.bioon.com/
http://www.bbioo.com/
http://bbs.bioon.com/bbs/index.php
http://www.dxy.cn/
http://bbs.biooo.com/
NCBI-American http://www.ncbi.nlm.nih.gov
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