Take out 4 sheets of paper from your notes section of your binders and head your papers. Assignment title should be:

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Take out 4 sheets of paper from your notes
section of your binders and head your papers.
Assignment title should be

• Cell Reproduction
• Chapter 10
• Level green book

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Goals

• Section 1 To learn how different organisms can
  grow, repair damaged cells, and reproduce because
  of cell division and mitosis.
• Section 2 To learn that sexual reproduction and
  meiosis ensure the preservation of species and
  diversity of life.
• Section 3 To learn that DNA contains the
  instructions for all life.

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Bell Work

• Go to page 275 for directions
• 5 minutes to complete foldable study organizer

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Directions for next slide!

• Before you read the chapter, respond to the
  statements below in your notebook.
• Write an A if you agree with the statement
• Write a D if you disagree with the statement
• After you read the chapter, look back to this
  page to see if youve changed your mind about any
  of the statements.
• If any of your answers changed, explain why.
• Change any false statements into true statements.
• Use your revised statements as a study guide.

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Get a copy of this chart from Ms. Etienne
Before you read A or D Statement After you read A or D
1. All cells cycles last the same amount of time.
2. Interphase lasts longer than other phases of a cells cycle.
3. Asexual reproduction requires two people.
4. Cell division and mitosis is the same in all organisms.
5. Meiosis always happens before fertilization.
6. A zygote is the cell formed when an egg and sperm join.
7. Diploid cells have pairs of similar chromosomes.
8. The exact structure of DNA is unknown.
9. A gene is a section of DNA on a chromosome.
10. Mistakes in copying DNA result in mutations.
11. Budding and regeneration can occur in most organisms.
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Section 1 Cell Division and Mitosis

• The Cell Cycle
• A life cycle begins with the organisms
  formation, is followed by growth and development,
  and finally ends in death.
• Length of Cycle
• Cell cycle is a series of events that takes place
  from one cell division to the next.
• The time it takes to complete a cell cycle is not
  the same in all cells.

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• Interphase
• Most of the life of any eukaryotic cell is spent
  in a period of growth and development known as
  interphase.
• During interphase, an actively dividing cell,
  such as a skin cell, copies its hereditary
  material and prepares for cell division
• Before a cell divides, a copy of the hereditary
  material must be made so that each of the two new
  cells will get a complete copy.
• Each cell needs a complete set of hereditary
  material to carry out life functions
• After interphase, cell division begins. The
  nucleus divides, and then the cytoplasm separates
  to form two new cells.

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• Mitosis and Cell Division
• The process where the nucleus divides to form two
  identical nuclei mitosis.
• Each new nucleus is identical to the original
  nucleus,
• The steps of mitosis in order are named prophase,
  metaphase, anaphase, and telophase.
• Steps of Mitosis
• When any nucleus divides, the chromosomes play
  the important part.
• Chromosome is a structure in the nucleus that
  contains hereditary material.
• During interphase (not part of mitosis- occurs
  before)
• each chromosome duplicates
• When the nucleus is ready to divide, each
  duplicated chromosome coils tightly into two
  thickened, identical strands called chromatids.
• During prophase
• The pairs of chromatids are fully visible when
  viewed under microscope.
• The nucleolus and the nuclear membrane
  disintegrate.
• Two small structures called centrioles move to
  opposite ends of the cell
• Between the centrioles, threadlike spindle fibers
  begin to stretch across the cell.

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• In metaphase
• The pairs of chromatids line up across the center
  of the cell
• The centromere of each pair usually become
  attached to two spindle fibers-one from each side
  of the cell.
• In anaphase
• Each centromere divides and the spindle fibers
  shorten
• Each pair of chromatids separate
• Chromatids move to opposite ends of the cells
• Chromatids are now called chromosomes

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• In Telophase
• Spindle fibers start to disappear
• Chromosomes start to uncoil
• TWO nuclei form
• Mitosis Ends Here!!!

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• After mitosis has ended, the cell still needs to
  split into two.
• The process by which the cytoplasm separates to
  form two new cells is known as CYTOKINESIS

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Contrasting Mitosis

• Animal cells

• Plant cells

• Appearance of the cell plate indicates that the
  cytoplasm is being divided (see figure 4 on page
  278).
• Do not have centrioles (see page 278).

• The cytoplasm divides as the cell membrane
  pinches in the middle of the cell

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Results of Mitosis and Cell Division

• Mitosis

• Cell Division

• Mitosis is the division of a nucleus
• Mitosis produces two new nuclei that are
  identical to each other
• The original cell no longer exists after mitosis

• Cell division allows for growth and replaces worn
  out or damaged cells
• You are larger and have more cells than a baby
  because of cell division
• Cell division is used by some organisms to
  produce new organisms

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Asexual reproduction

• There are two types of reproduction sexual and
  asexual.
• In asexual reproduction, a new organism
  (sometimes more than one) is produced from only
  one organism
• This new organism will have the same hereditary
  material as the parent organism
• Types of asexual reproduction
• Cellular Asexual Reproduction mitosis, cell
  division and fission are all examples of cellular
  asexual reproduction

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• Mitosis is when the nucleus divides into two
  nuclei.
• Cell division is when one cell divides into new
  cells.
• Fission is a type of asexual reproduction used by
  bacteria. During fission, the unicellular
  bacterium (which does not have a nucleus), copies
  its genetic material and then divides into two
  identical organisms.
• Keep in mind, bacteria are prokaryotes and can
  undergo FISSION and not MITOSIS.
• Eukaryotes can undergo MITOSIS and not FISSION

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• Other types of asexual reproduction
• Budding made possible because of mitosis and
  cell division. In budding, a bud grows on the
  adult, when it becomes large enough, it breaks
  away to live on its own.
• Regeneration process that uses mitosis and cell
  division to regrow body parts. If organisms that
  can undergo regeneration break into pieces, a new
  organism can grow from each piece. Example of
  organisms that can use regeneration sponges,
  planaria and sea stars

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Section 2 Sexual Reproduction and Meiosis

• Sexual reproduction
• Sexual reproduction- two sex cells, sometimes
  called an egg and a sperm, come together.
• Sperm- sex cell formed in a male reproductive
  organs
• Eggs- sex cell formed in the female reproductive
  organs.
• Fertilization- the joining of an egg and a sperm.
• Zygote- cell that forms during fertilization.

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• Diploid Cells
• Typical human body cell has 46 chromosomes and is
  considered a diploid cell.
• Each chromosomes has a similar pair which makes
  23 pairs of chromosomes.
• Diploid is when cells have PAIRS of similar
  chromosomes.
• Example 23 PAIRS of chromosomes in a typical body
  cell-
• 23 pairs of chromosomes 46 chromosomes
• Haploid Cells
• A Sex cell does not have pairs of chromosomes so
  it is considered a haploid cell.
• Haploid means single form
• Human sex cells have 23 chromosomes (which is
  half of the amount of chromosomes in body cells
  not in pairs)

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Meiosis and Sex cells

• Meiosis- process that produces haploid sex cells.
• During meiosis two divisions happen (meiosis I,
  and meiosis II)

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• Meiosis I
• Before meiosis, each chromosome duplicates.
• The events in prophase I are similar to those of
  prophase in mitosis
• Unlike mitosis, in meiosis, each duplicated cells
  comes near its similar duplicated mate.
• In metaphase I, the pairs of duplicated
  chromosomes line up in the center of the cell.
• Then centromere of each chromatid pair becomes
  attached to one spindle fiber so the chromatids
  do not separate in anaphase I.
• The two pairs of chromatids of each similar pair
  move away from each other to opposite ends of the
  cell
• In telophase I, the cytoplasm divides, and two
  new cells are formed

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• Meiosis II
• The two cells formed in meiosis I, begin meiosis
  II
• In Prophase II, the duplicated chromosomes and
  spindle fibers reappear in each new cell.
• In metaphase II, the duplicated chromosomes move
  to the centromere now attaches to two spindle
  fibers instead of one.
• Then the chromatids separate and move to opposite
  ends of the cell, and each cells become an
  individual chromosome in anaphase II.
• In telophase II, the spindle fibers disappear and
  a nuclear membrane forms around each set of
  chromosomes.
• When meiosis is finished, the cytoplasm divides.

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• Summary of meiosis
• In meiosis I, two cells are formed
• In meiosis II, both of these cells form two
  cells.
• From a human cell with 46 paired chromosomes,
  meiosis produces four sex cells each with 23
  unpaired chromosomes.

• Mistakes of meiosis
• Meiosis occurs many times in reproductive organs
• Mistakes can produce sex cells with too many or
  too few chromosomes
• Sometimes zygotes are produced from these sex
  cells
• If the zygote lives, every cell in the organism
  that grows from that zygote usually have the
  wrong number of chromosomes
• Organisms that have the wrong number of
  chromosomes may not grow normally.

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Section 3 DNA

• What is DNA?
• Code used by cell that is stored in hereditary
  material
• This chemical code is called DNA (Deoxyribo
  Nucleic Acid)
• DNA contains information for organism growth and
  function

• During cell division DNA code is copied and
  passed on to the new cells
• This passing on of DNA ensures that new cells
  have the same coded information as the old cells
• Every cell formed in your body contains DNA

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DNA
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History

• Discovering DNA

• DNAs structure

• Scientists have known since mid-1800s that
  nuclei contain nucleic acids
• By 1950, chemists learned what nucleic of DNA was
  made of but structure of DNA was still unknown
• Click on this link
• http//www.brainpop.com/science/cellularlifeandgen
  etics/dna/

• In 1952- Rosalind Franklin discovered that DNA
  consisted of 2 chains of molecules in a spiral
  form
• Used X-ray technique to determine this
• In 1953- James Watson and Francis Crick made a
  model of DNA molecule

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DNA Model

• D Sugar (deoxyribose)
• P Phosphate
• Nitrogen bases
• A Adenine
• T Thymine
• C Cytosine
• G Guanine
• Amount of Cytosine in cells always equals amount
  of guanine in cells. Dame goes for amounts of
  thymine and adenine.

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Copying DNA

• Before mitosis or meiosis, amount of DNA in the
  nucleus is doubled
• The Watson and Crick model illustrates how this
  takes place
• Two sides of DNA unwind and separate
• Each side becomes a patter on which new side
  forms
• See images

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Genes
A gene is a section of DNA on a chromosome

• Making proteins

• Ribonucleic Acid (RNA)

• Genes are found in the nucleus BUT proteins are
  made in the cytoplasm
• The codes to make proteins are carried from the
  nucleus to the ribosomes by RNA (remember
  ribosomes make proteins)

• Made in the nucleus on a pattern of DNA
• DNA looks like a ladder but RNA is a ladder with
  its rungs cut in half
• Like DNA, RNA has the nitrogen bases Guanine,
  Adenine, Cytosine but RNA has the nitrogen base
  Uracil instead of thymine
• The sugar phosphate in RNA contains the sugar
  Ribose and NOT Deoxyribose as in DNA

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RNA continued

• Three main kinds of RNA
• Messenger RNA (mRNA)
• Protein production begins when mRNA moves into
  the cytoplasm
• Ribosomal RNA (rRNA)
• Ribosomes are made of rRNA
• Transfer RNA (tRNA)
• tRNA in the cytoplasm bring amino acids to these
  ribososmes
• See page 293 of the Green Book for more details

• Above you have RNA on the left, DNA on the right

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Controlling Genes

• Just because most cells in organisms have the
  same chromosomes and the same genes does not mean
  they make the same proteins
• Multicellular organisms use thousands of genes
  that they contain to make proteins
• Cells use only the genes that direct the making
  of proteins that it needs
• Muscle proteins made in muscle cells and not in
  nerve cells
• Cells can also turn genes on and off
• See how on page 294

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Mutations

• Mistakes can occur when DNA is being copied and
  DNA ends up not being copied properly
• These mistakes are called mutations
• When are mutations likely to occur?
• What are the results of mutation?
• Please read pages 294 and 295 to answer the
  following questions
• Look at figure 19 on page 295

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Reviewing

• Please read pages 276 through 295 again and
  complete chapter review on pages 300, 301 as
  practice.
• Fill out the After you read portion of the
  chart on slide 5 of the power point or page 276B
  of the Green Book
• Sign onto Brainpop.com, watch videos DNA, RNA
  and Genetic Mutations
• Username palmbeach
• Password palmbeach