Chapter 10: Cell Cycle Notes

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Chapter 10 Cell Cycle Notes
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Why Divide?
The cell theory states that All cells come
from other living cells.

• Cells divide for the survival of the individual
  organism
• Cells divide for the survival of the species
  (group of similar organisms)

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Cells divide for the survival of the individual
organism?

• Cell division is used for growth, development,
  maintenance, and repair of the organism. This is
  carried out by
• Mitosis- division of body cells to make more of
  the same kind of cell.
• The parent cell is the original cell inside the
  organism that will divide.
• The daughter cells are the two identical cells
  created when the parent cell divides.

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Cells divide for the survival of the species ?

• To reproduce more organisms that look similar to
  their parents
• Sexual reproduction -two separate organisms
  produce egg and sperm that must combine or fuse
  together to produce offspring.
• Meiosis? process of making egg cells and sperm
  cells.
• Fertilization? the fusion of egg and sperm to
  produce a new organism.

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Cells divide for the survival of the species ?

• To reproduce more organisms that look similar to
  their parents
• Asexual reproduction- offspring are produced by
  only one individual organism.
• Spores are produced by mold and other fungi that
  grow all by themselves into more fungi.
• Binary fission is the process of a bacterium
  splitting in two new bacteria

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Cell Cycle

• Cell Cycle- is defined as the life of a cell from
  the beginning of one interphase to the beginning
  of the next interphase. (with cell division in
  between)
• Step (1.) Interphase (G1,S G2 phases)
• Step (2.) Cell Division
• Mitosis-division of nucleus
• Cytokinesis- division of cytoplasm

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Cell Cycle Interphase

• Step 1 Interphase is the growth and
  development phase of the cell cycle. Three parts
  
• (1.) Growth One or G1 phase
• (2.) Synthesis or S phase (make DNA)
• (3.) Growth Two or G2 phase

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G1 phase

• initial growth phase of the cell.
• The cell grows and carries out its routine
  functions.
• This is the longest phase of interphase.
• Many cells stop growing and get stuck in this
  phase for the entire life of the organism (Ex.
  Nerve cells).
• Other cells get stuck in G1 of interphase until
  cell division is needed for growth or repair.

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S phase (synthesis)

• is when DNA replication occurs.
• After DNA replication the cell has two complete
  copies of its DNA.
• At this point, the cell is committed to dividing.

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G2 phase

• the cell continues to grow and the final
  preparations for cell division are made.

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G2
G1
S
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Cell Cycle Cell Division

• Step 2 Cell Division -the creation of two
  daughter cells from one parent cell.
• Each daughter cell will have the same number of
  chromosomes as the parent cell.
• Two Parts of Cell division
• Mitosis and Cytokinesis

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Cell Division Mitosis

• Mitosis division of the nucleus. It is a
  synchronized set of events that will separate
  chromosomes, so that the two nuclei formed will
  be identical.
• It is the beginning of cellular division.
• (PMAT)-
• Prophase, Metaphase, Anaphase, Telophase

• Mitosis Animation Simple

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Cell Division Cytokinesis

• Cytokinesis division of the cell cytoplasm. It
  is the physical separation of the cytoplasm into
  two new daughter cells.
• It is the end of cell division.
• New cells pinch off from each other in animal
  cells. In plants, a cell plate is formed, because
  plants also have cell walls to form.

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Vocabulary
Slide 5

• 1. Chromosome coiled DNA structures within the
  nucleus containing genetic information that is
  passed on from generation to generation
• 2. Sister Chromatid one of two identical
  sister parts of a duplicated chromosome-formed
  during S phase
• 3. Centromere (A) chromosome region that joins
  2 sister chromatids

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Prophase 1st Phase

• 1. DNA coils becomes chromosomes
• 2. Centrioles move to opposite ends of cell
• 3. Spindle fibers attach to chromosomes
• 4. Nuclear membrane breaks down

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Metaphase

• 1. Spindle fibers push pull chromosomes until
  they line up across center of cell
• 2. Centromere of each chromosome pair is
  attached to a spindle fiber

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Anaphase

• 1. Spindle fibers shorten paired chromatids
  separate
• 2. Spindle fibers pull separated chromosomes to
  opposite ends of the cell
• 3. Centromere of each pair divides now have
  individual chromosomes

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Telophase

• 1. Chromosomes begin to uncoil and decondense
• 2. Nuclear membrane reforms around each new set
  of chromosomes

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Cytokinesis

• Cytokinesis is division of the cytoplasm
• Distributes the organelles
• In animal cells, the cell membrane pinches in
  two.
• In plant cells, a cell plate forms across the
  middle.

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What Phase Of the Cell Cycle Is It?
A
B
C
Anaphase
Cytokinesis
Telophase
D
E
F
Interphase
Prophase
Metaphase
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CANCER

• is the caused by uncontrolled cellular division.
  
• Typically, most cells dont divide unless it is
  for repair or maintenance.
• Cancerous cells keep dividing crowding out and
  stealing nutrients from healthy tissue.
• Cancer kills when a mass of cancer cells called
  a tumor interferes with the functions of major
  organs.

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BRAIN TUMOR
BREAST TUMOR
ORAL CANCER
PANCREATIC CANCER
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The picture on the left shows a healthy right
lung, and a small discolored left lung. This
indicates the presence of tumors, as seen in the
picture on the right.