Download What is Mitosis?

Mitosis 12­2013.notebook
November 19, 2015
• Cell division (cell reproduction)
BIO.10 I can use a model to illustrate the role of cellular division (asexual/
sexual) and differentiation in producing and maintaining organisms. NGSS.HS.LS1­4 & LS3­2
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1 I can identify and explain cell division.
2 I can differentiate the hierarchical structure of genetic material.
3 I can explain the major events of the cell cycle.
4 I can relate the role of the cell cycle to the onset of cancer.
5 I can predict how changes in chromosome number or structure can affect development.
intro video: http://www.youtube.com/watch?v=Q6ucKWIIFmg
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Mitosis 12­2013.notebook
November 19, 2015
Reproduction of Organsims
Asexual
(prokaryotes)
a single parent passes copies of all the genes to each of its offspring
Sexual
(eukaryotes)
two parents pass on half their genes to their offspring
Gametes ­organism’s reproductive cells sperm or egg cells.
46 chromosomes total
(humans)
* 23 from mom
* 23 from dad
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Mitosis 12­2013.notebook
Binary Fission
November 19, 2015
(asexual reproduction)
Prokaryotic cells reproduce by binary fission of a single parent.
ex: bacteria
During binary fission the simple, circular DNA is copied. Duplicates attach to opposite sides. Cytoplasm pulls apart and splits in two, each section contains identical DNA.
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Mitosis 12­2013.notebook
November 19, 2015
Genes, DNA and Chromosomes
DNA: nucleic acid that tells cells
which proteins to make:
a chemical blueprint
Chromosome: DNA wound around proteins; makes an X shape
Chromatid: two exact copies of DNA that makeup the halves of a chromosome attached a central point called a centromere
Gene: segment of DNA that codes for a specific protein. A gene contains 4 nitrogen bases, which we show as the letters A, T, C and G. Homologous Chromosomes: a set of chromosomes, one from each parent, that contain similar genetic content (code for the same thing: eye color etc...)
http://www.youtube.com/watch?v=gbSIBhFwQ4s
http://www.youtube.com/watch?v=C8OL1MTbGpU
What is a chromosome?
Chromatin: DNA ­not wound up or condensed into a chromosome
(spaghetti)
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Mitosis 12­2013.notebook
November 19, 2015
Terminology­Review
picture
1.Point where two chromatids connect
term
2.One of the two identical strands of DNA that make up a chromosome
3.Tightly coiled mass of DNA and protein
4. The mass of DNA and protein that makes up a Chromosome
(not wound up)
Chromatin Chromosome Chromatid Centromere 5
Mitosis 12­2013.notebook
November 19, 2015
When Cells Divide
Mitosis
• Growth • (initial and renewal) Meiosis • Reproduction
• Repair occurs in somatic cells
(body cells)
occurs in gametes
(sex cells)
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Mitosis 12­2013.notebook
November 19, 2015
The Cell Cycle
What are the phases?
1. Interphase:
• G 1 phase ­ growth
• S phase ­ synthesis DNA replication
• G 2 phase ­ growth
2. Mitosis ­nucleus divides in 4 stages PMAT
3. Cytokinesis­
cytoplasm divides
Stages of Mitosis p.130
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Mitosis 12­2013.notebook
November 19, 2015
• Bio 10.3 I can explain the major events of the cell cycle.
Interphase
• Longest stage in the cell cycle
• Technically not part of Mitosis
(but often times will be shown with it)
• Phases: 1.
(G1) First Growth phase
2.
(S) Synthesis phase
3.
(G2) Second Growth phase
• Cell growth and construction of new organelles
• Copies of DNA are made
• Growth and preparation for cell division
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Mitosis 12­2013.notebook
November 19, 2015
• Bio 10.3 I can explain the major events of the cell cycle.
What is Mitosis?
• Mitosis is the process of cell division that forms two new identical cells called daughter cells (diploid)
• The number of chromosomes in the nucleus remains the same.
• Produces somatic (body) cells Meiosis ends with half the number of chromosomes and produces gametes
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Mitosis 12­2013.notebook
November 19, 2015
• Bio 10.3 I can explain the major events of the cell cycle.
4 Stages of Mitosis
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Prophase
Metaphase
Anaphase
Telophase
• "I Passed My Algebra Test"
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Mitosis 12­2013.notebook
November 19, 2015
• Bio 10.3 I can explain the major events of the cell cycle.
Cytokinesis
• Cytoplasm is divided
The Final Result
• 1 cell splits into two cells • Two identical copies are called "daughter cells“
• Same number of chromosomes for all cells
• Interphase begins and the process repeats...and repeats…and repeats…
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Mitosis 12­2013.notebook
November 19, 2015
Bio 10.4 I can relate the role of the cell cycle to the onset of cancer.
Cancer
Cancer: a disease in which cells reproduce at an
abnormally fast rate. ( uncontrollable mitosis or
mitosis gone wild)
*cells are disrupted
*genes become mutated
Possible Causes:
1) certain chemicals
2) radiation (x-rays)/
sun
3) viruses
4) Probable genetic link
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Mitosis 12­2013.notebook
November 19, 2015
What is the result of mitosis?
When is DNA copied?
90% of cell's life cycle is spent is this phase:
Cancer is:
Sequence of events that occurs in a cell from one mitotic division to the next:
Type of cells that undergo mitosis:
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Mitosis 12­2013.notebook
Cell Cycle and Mitosis review
November 19, 2015
Name_________________________________________ hour____
1. Write the initials for the order of the 6 steps of the cell cycle. ____, ____, ____, ____, ____, ____
2. In ____________________________,
the chromosomes are lined up along the middle. Spindle fibers are attached to the centromere of the chromosomes.
3. In ____________________________,
the chromosomes uncoil, the spindle dissolves, and the nuclear membrane forms at each pole.
4. In ____________________________, the centromeres divide, and each chromatid (now called chromosomes) move toward the opposite pole.
5. In _____________________________, chromosomes coil up and become visible, spindle fibers begin to form, and the nuclear membrane dissolves.
6. In _____________________________, the cytoplasm divides to make two genetically identical daughter cells.
7. In _____________________________,
the cell undergoes growth and prepares for cell division. This is the longest stage in the cell cycle.
8. Write 1, 2, and 3 to show the order of the 3 phases of interphase. Then include the symbol for each phase.
_____­ Growth and preparation for mitosis, symbol:_____
_____­ first cell growth, symbol:_____
_____ ­DNA synthesis, symbol:____
9. Two reasons for cells to undergo mitosis are: ______________ and _________________
10.What is the result of mitosis?
(in terms of chromosome number and number of cells produced, and the term for these resulting cells?)
Definitions:
DNA
Centromere
Mitosis
chromatin
Binary fission
Chromosome
Cancer
Chromatid
Somatic cells
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