10 Generation Pedigree Chart Template by jyk19184

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									                    Warm up
• DNA is found in all living things. The
  shape of DNA is like a twisted ladder and
  is called a double helix. One molecule of
  DNA can contain millions of atoms. When
  unraveled, there are about 6 feet of DNA
  in each of your bodies cells.
• What does DNA stand for?
• What kind of information is stored on
  DNA?

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                    What is Heredity?
• Traits – traits are the characteristics of an
  organism.
• During fertilization, male and female sex
  cells join together.
• Each of these sex cells contains material
  that affects the development of the
  offspring.
• Traits that are passed from parent to
  offspring are called inherited traits.
• Eye color is an example of inherited traits.
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                    Heredity
• The passing of traits from parents to
  offspring is called heredity.
• The field of biology that studies heredity is
  called genetics.




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              Gregor Mendel
• Gregor Mendel was an
  Australian monk. He was one
  of the first people to study
  heredity.
• Mendel showed how the traits
  in pea plants are passed from
  one generation to the next
• He is called the Father of
  Genetics
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• Mendel used seven different
  pairs of traits:
• 1) Seed form - round or
  wrinkled.
• 2) Color of seeds - yellow or
  green (contents).
• 3) Color of seed coat white or
  grey.
• 4) Color of unripe seedpods -
  green or yellow.
• 5) Shape of ripe seedpods -
  inflated or constricted between
  seeds.
• 6) Length of stem - short 9 - 18
  inches of long 6 - 7 feet.
• 7) Position of flowers - axial (on
  stem) or terminal (at tip of
  stem).
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                    Heredity of Twins
• Twins are siblings born at the same time.
• Two types of twins - fraternal and identical.




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                    Identical Twins
                    • Identical twins develop
                      from one egg,
                      fertilized by a single
                      sperm.
                    • Identical twins are
                      genetically identical.
                    • They inherit the exact
                      same traits.
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            Fraternal Twins
• Fraternal twins develop from
  two separate eggs that have
  been fertilized by two
  separate sperm cells.
• Fraternal twins are
  genetically different from
  each other. They can be
  different sexes.




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• Twin animation Video
• http://pennhealth.com/health_info/animatio
  nplayer/twins.html




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                    Genetic Traits Lab
• Choose a partner
• Complete the data table for you and your
  partner. Be neat. Use a ruler & complete
  headings!
• Collect the class data and complete the
  rate of frequency data table for the class
• Everyone must have a completed data
  tables
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Name ___________________-

Trait                               Yes        NO

Tongue Rolling
Widow‘s Peak
Dimples
Pierced Ears
Earlobe Attachment                  attached   free
Mid-Digital Finger Hair
Naturally Curly Hair
Cleft Chin
Hitchhiker's thumb
Can see the color‘s red and green
Allergies
Right-handed
Freckles30, 2010
November                                              11
                    Assignment
• Complete worksheet 3-1
• Complete study worksheet 11-1




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                           Warm up
• Normal human body cells each contain 46 chromosomes. The cell
  division process that body cells undergo is called mitosis and
  produces daughter cells that are virtually identical to the parent cell.
  Answer the questions that follow.
• 1. How many chromosomes would a sperm or an egg contain if
  either one resulted from the process of mitosis?


• 2. If a sperm containing 46 chromosomes fused with an egg
  containing 46 chromosomes, how many chromosomes would the
  resulting fertilized egg contain? Do you think this would create any
  problems in the developing embryo?


• 3. In order to produce a fertilized egg with the appropriate number
  of chromosomes (46), how many chromosomes should each sperm
  and egg have?


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                    Gametes
                    • Every body cell of an
                      animal contains the same
                      number of chromosomes
                    • Sperm cells and egg cells
                      are reproductive cells
                    • Reproductive cells are
                      also called gametes


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• Gametes develop form
  special cells in the
  body.
• During the formation of
  gametes, the number of
  chromosomes is cut in
  half.
• Each gamete contains
  only 1/2 as many
  chromosomes as a
  body cell
• The process by which
  gametes form is called
  Meiosis
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Number of Chromosomes in Various Organisms

Organism              Body Cells   Gametes

Fruit Fly             8            4

Bull Frog             26           13

Human                 46           23



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                    Meiosis

• The process of
  meiosis occurs in 2
  parts, meiosis I and
  Meiosis II.
• Meiosis includes 2
  cell divisions
  instead of 1


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                    Prophase part 1
• Chromosomes
  replicate and
  nuclear
  membrane
  disappears
• Crossing over
  causes genetic
  variations

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• In prophase I, doubled
  chromosomes condense
  again. . . BUT, UNLIKE
  mitotic prophase, the
  members of each
  chromosome pair attach
  to each other. These
  paired chromosomes
  actually exchange
  pieces of themselves
  with each other -- called
  crossing over.

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                    Metaphase part 1
• Chromosomes
  line up in pairs




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                    Anaphase Part 1
• Chromosome
  pairs separate




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                    Telophase Part 1
• Cells Pinch
  Apart




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                    Prophase part 2
• Chromosomes do not need to replicate




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                    Metaphase part 2
• Chromosome copies line up single file




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                    Anaphase Part 2
• Chromosome copies split and separate




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                    Telophase part 2
• Cells pinch apart and nuclear membrane
  forms




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                    • Four daughter
                      cells are formed
                      with half the
                      number of
                      chromosomes
                    • These new cells
                      are called
                      gametes

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• Meiosis 1 is similar to mitosis except
  that the chromosome copies do not
  split
• Instead, the chromosome pairs
  separate.
• So we get 2 daughter cells that are
  different from each other




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• After Meiosis II, the daughter cells formed
  only have ½ the chromosomes compared
  to the number of chromosomes in normal
  body cells
• Human gametes only contain 23
  chromosomes



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                    Nondisjunction
• During Meiosis, chromosome pairs
  separate to form gametes (sex cells)
• Sometimes the gametes do not separate
  correctly.
• This is called nondisjunction




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• In nondisjunction, both chromosome pairs
  go to the same gamete
• As a result one gamete has too many
  chromosomes and the other gamete has
  too few.
• If either of these gametes unites with a
  normal gamete during fertilization, the
  organism does not develop properly.



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• Down Syndrome is
  caused by
  nondisjunction
• The body cells of a
  person with Down
  Syndrome contain 47
  chromosomes instead
  of 46.

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                    Assignment
• Complete worksheet 3-2
• Compete Study guide for section 11-4
• Complete DNA challenge. I want at least
  60 words!




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                    Warm Up
• Read the article ―DNA Structure‖
• Complete the blanks and answer the
  questions.
• Be prepared to share.




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What is DNA?
• Chromosomes
  are made of large
  molecules called
  DNA
• DNA stands for
  deoxyribonucleic
  acid


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                    • DNA structure was
                      discovered in 1953 by
                      an American scientist,
                      James Watson , and a
                      British Scientist,
                      Frances Crick.
                    • They created the first
                      model of a DNA
                      molecule
November 30, 2010                              39
           Structure of DNA
• DNA looks like a twisted
   ladder.
• We call this structure a double
   helix.
• The sides of the ladder are
   made up of sugars and
   phosphates.
• The steps of the ladder are
   made of nitrogen bases.
• Each base pairs with another
   specific base to form the steps
   of 30, 2010
Novemberthe ladder                   40
      Base Names
• There are 4
  nucleotide bases
  that make up a
  DNA molecule.
• They are adenine,
  thymine, cytosine
  and guanine.


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                    Base Pairing
                             • In a double
                               helix, Adenine
                               always pairs
                               with thymine
                               and cytosine
                               always pairs
                               with guanine.



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                    Replication
• During mitosis, cellular DNA copies itself.
  This is called replication.
• The DNA ladder unzips itself and new
  nitrogen bases pair up with the ladder.
• After replication, we have new DNA
  strands that are exact copies of the
  original DNA molecule.


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                    The Role of DNA
• A single DNA molecule, or ladder, can
  have thousands of steps, or base pairs.
• The number and arrangement of these
  steps forms a genetic code.




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• DNA does three critical things:
1. Genes carry information from one
   generation to another.
2. Genes determine the heritable (traits that
   are passed to offspring) characteristics of
   an organism.
3. Copy DNA every time cell division
   occurs.



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                    Assignment
• Complete worksheet 3-3
• Complete text study sheets 12-1 and 12-2




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                      Warm Up
• DNA contains the information that a cell needs to carry
   out all of its functions. In a way, DNA is like the cell‘s
   encyclopedia. Suppose that you go to the library to do
   research for a science project. You find the information
   in an encyclopedia. You go to the desk to sign out the
   book, but the librarian informs you that this book is for
   reference only and may not be taken out.
1. Why do you think the library holds some books for
   reference only?
2. If you can‘t borrow a book, how can you take home the
   information in it?
3. All of the parts of a cell are controlled by the information
   in DNA, yet DNA does not leave the nucleus. How do
   you think the information in DNA might get from the
   nucleus to
November 30, 2010 the rest of the cell?                        48
                     RNA


• DNA controls an organism‘s traits by
  producing certain proteins at certain times.
• This is called protein synthesis.
• Proteins are made of molecules called
  amino acids
• These amino acids are made by the
  ribosomes of cells


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• The DNA code is located inside the
  nucleus of a cell.
• A special molecule carries the code from
  the nucleus to the ribosome.
• This molecule is RNA, or ribonucleic acid.




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                    RNA Structure
• RNA has only
  one side of the
  ladder shape.
• RNA contains the
  nitrogen base
  uracil instead of
  thymine.



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                    How it works?
• RNA copies the code from the DNA strand
  and then carries it to the ribosome.
• RNA acts as a pattern on which proteins
  can be built.
• Ribosomes read the RNA strand and
  attach the correct amino acids.
• The amino acids link together and form a
  protein

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                    Types of RNA
1. Messenger RNA – Contain instructions
   for assembling amino acids and proteins.
2. Ribosomal RNA – Found inside
   ribosomes. Helps the ribosome make
   new proteins
3. Transfer RNA – transfers each amino
   acid to the ribosomes as it is specified by
   the codes on mRNA.
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       Transcription & Translation
                    • During transcription, the
                      DNA molecule is unzipped
                      and separated. An enzyme
                      uses one strand of DNA as
                      a template to make a strand
                      of mRNA.
                    • During translation, the cell
                      uses information from the
                      mRNA to produce proteins.


November 30, 2010                                54
                    Transcription
• http://www-
  class.unl.edu/biochem/gp2/m_biology/ani
  mation/gene/gene_a2.html
• http://www.stolaf.edu/people/giannini/flash
  animat/molgenetics/transcription.swf




November 30, 2010                           55
                    Translation
• http://www-
  class.unl.edu/biochem/gp2/m_biology
  /animation/gene/gene_a3.html
• Complete internet lab




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                    Assignment
• Complete study Guide 12-3
• Complete worksheet messenger rna




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                    Warm Up
• Describe three differences between RNA
  and DNA
• Be specific and use complete sentences




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         Chromosomes
• Fine, threadlike
  structures located in the
  nucleus of the cell are
  called chromosomes.
• Chromosomes control
  heredity



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 This is a real picture of a person's chromosomes –
 taken from a single cell, stained and spread on a microscope
 slide.
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                    Karyotypes
                          • A karyotype is a
                            display of an
                            organism‘s
                            chromosomes,
                            organized by size
                            and shape.
                          • Sometimes the
                            chromosomes in
                            a karyotype are
                            numbered.
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            Chromosome Structure
• Chromosomes are
  made of chromatin.
• Chromatin is a very
  long, thin strand of DNA
• The strands are
  wrapped around special
  proteins that help to
  keep the chromatin in
  an x-shape.

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• Each side of the x shaped chromosome is
  called a chromatid.
• Chromatids are exact copies of each
  other.
• They are held together by a centromere.
• Chromatin does not usually look like this. It
  only forms tight coils when it is about to
  divide.



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   Chromatin




                    Chromatid
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                    Chromosome Pairs
• In organisms that sexually reproduce,
  chromosomes exist in pairs.
• This is because each parent contributes to
  the same chromosome.
• Karyotypes show chromosomes arranged
  in pairs.




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• To "read" a set of human chromosomes,
   scientists first use three key features to identify
   their similarities and differences:
1. Size.
2. Banding pattern. The size and location of bands on
   chromosomes make each chromosome pair unique.
3. Centromere position. Centromeres are regions in
   chromosomes that appear squeezed together.
• Using these key features, scientists match up the
  23 pairs -- one set from the mother and one set
  from the father.




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                    Alleles
• Alleles are different versions of the same
  gene.
• Alleles for a specific gene are always
  found in the same location on the same
  chromosome.
• Example – plants may have an allele for
  purple flowers or an allele for white
  flowers.


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                    Assignment
• Complete Karyotype Lab
• Complete worksheet 3-4
• Read study sheet 14-2




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                    Bell Ringer
• Read the Chris Burke story
• Fill in the blanks
• Answer the questions.




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                    Warm Up
•     Answer the following questions using
      complete sentences.
1.    Where are chromosomes located?
2.    When does Chromatin form a
      Chromatid?
3.    Where are genes located?
4.    What are alleles?

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                    Mutations
• A Mutation occurs when a DNA gene is
  damaged or changed in such a way as to
  alter the genetic message carried by that
  gene.
• A Mutagen is an agent of substance that
  can bring about a permanent alteration to
  the physical composition of a DNA gene
  such that the genetic message is changed.

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          Chromosomal mutations
• Mutations may involve whole chunks of
  chromosome or just changes in single
  bases.
• A length of chromosome may be
  translocated to another place on the
  chromosome, or be inverted.
• Whole chromosomes may fuse.


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                    Mutagens
1.    Chemical Mutagens
2.    Radiation
3.    Sunlight (ultraviolet radiation)
4.    Spontaneous mutations




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    Genetic Disorders caused by
    Chromosomal Abnormalities




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                    Stumpy the duck
                        • Stumpy, an 8-day-old
                          duckling born in
                          Britain, has a rare
                          mutation: 4 legs
                        • A rare mutation has left
                          the eight-day-old
                          duckling with two nearly
                          full-sized legs behind the
                          two he runs on.

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                    And then there were two..Stumpy without his third
                    limb

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                    Lionhead Rabbit
•




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                American Curl
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                    Cornish REx




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                    Sphinx




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                    Webbed Feet




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            Down Syndrome
• Down Syndrome is a genetic
   disorder caused by extra
   genetic material. It affects
   over 350,000 people in the
   United States alone and is the
   most common (1 in 800 live
   births) imbalance in the
   number of autosomes in
   people. The effects of Down
   Syndrome vary greatly from
   person to person but can
   include mental retardation,
   eyes that slant upward, and
   heart defects.
• People with Down Syndrome
   have 3 copies of chromosome
   21. For this reason, Down
   Syndrome is also called
   "Trisomy 21".
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                       Turner Syndrome
                    • Turner Syndrome affects 60,000
                      girls and women in the United
                      States.
                    • Symptoms include short stature
                      and lack of ovarian development.
                      Other features, such as webbed
                      neck, arms that turn out slightly at
                      the elbow, and a low hairline in
                      the back of the head are
                      sometimes seen.
                    • Women and girls with Turner
                      Syndrome have only one X
                      chromosome.
                    • the single X chromosome comes
                      from the mother's egg because the
                      father's sperm that fertilizes the
                      egg is missing a sex chromosome.
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             Klinefelter Syndrome
• Klinefelter Syndrome
  occurs in 1 in 500 to 1 in
  1000 live births.
• People with this disorder
  are often tall and usually
  do not develop secondary
  sex characteristics such as
  facial hair, or underarm
  and pubic hair.
• Men and boys with
  Klinefelter Syndrome have
  a Y chromosome and 2 X
  chromosomes.




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             Cri du chat Syndrome
                       • Cri du chat is a rare syndrome
                         (1 in 50,000 live births)
                         caused by a deletion on the
                         short arm of chromosome 5.
                         The name of this syndrome is
                         French for "cry of the cat,"
                         referring to the distinctive cry
                         of children with this disorder.




November 30, 2010                                      96
                    Williams Syndrome




• Williams Syndrome is caused by a very small chromosomal
  deletion on the long arm of chromosome 7.
• Because they lack the elastin protein, people with Williams
  Syndrome have disorders of the circulatory system, also
  known as vascular disorders.
• The chromosomal deletion that causes Williams Syndrome
  is so small that it cannot be seen in a karyotype. However,
  the deletion can be observed using a special technique
  called fluorescent in situ hybridization, or FISH.
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                    Patau Syndrome
• Trisomy 13 – extra chromosome #13




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Edward Syndrome – Trisomy 18
• It is caused by the presence of three —
  instead of two — chromosomes 18 in a
  fetus or baby's cells.




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                    XYY syndrome
• XYY syndrome is an trisomy of the sex
  chromosomes in which a human male receives
  an extra Y chromosome, producing a 47,XYY
  karyotype.
• Most often, this chromosomal change causes no
  unusual physical features or medical problems.
• 47,XYY boys have an increased risk of learning
  difficulties (in up to 50%) and delayed speech
  and language

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                    • There are currently no treatments
      Progeria        for progeria, which is a genetic
                      disorder estimated to affect one
                      child in 4 million.
                    • When they are born, children with
                      progeria appear normal
                    • But, as they grow older, they
                      experience growth retardation and
                      show dramatically accelerated
                      symptoms of aging -- namely hair
                      loss, skin wrinkling and fat loss.
                    • Accelerated cardiovascular
                      disease also ensues, typically
                      causing death from heart attack or
                      stroke at about the age of 12.


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                    Anencephaly




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   Hydrocephalic - enencephalic




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                    Assignment

• Complete study guide 12-4




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                    Bell ringer
• What are the four types of mutagens?




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                                  Warm up
    Parents                       First Generation   Second Generation
    Long stems  short stems      All long           787 long: 277 short
    Red flowers  white flowers   All red            705 red: 224 white
    Green pods  yellow pods      All green          428 green: 152 yellow
    Round seeds  wrinkled seeds All round           5474 round: 1850 wrinkled
    Yellow seeds  green seeds    All yellow         6022 yellow: 2001 green

• 1. In the first generation of each experiment, how do the
  characteristics of the offspring compare to the parents‘
  characteristics?
• 2. How do the characteristics of the second generation
  compare to the characteristics of the first generation?

  November 30, 2010                                                              119
                    Genes and Traits
• Genes are inherited factors that produce
  certain traits.
• Each trait of an organism is determined by
  at least one gene from each parent.




November 30, 2010                         120
Homozygous and heterozygous
• An organism is homozygous if it has 2 like
  genes for a given trait. (TT, tt)
• Organisms that have two unlike genes for
  a trait are heterozygous for that trait (Tt)




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                    Dominant Genes
• When a dominant gene is present the
  recessive genes are all hidden.
• But if there are no dominant genes
  around we can see recessive genes




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                    Gene Symbols
• Organisms have at least 2 genes for most
  traits.
• Symbols are used to represent the
  combination of genes.
• An uppercase letter represents a
  dominant trait.
• A lowercase letter represents a recessive
  trait.


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                    Predicting Traits
• Punnett squares are charts that show
  possible gene combinations and the
  probability of each combination occurring.




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         Steps for creating a Punnett
                    Square
1. Draw a box with 4 squares in it.
2. Write the genes for the father across the
   top.
3. Write the genes for the mother down the
   side.
4. Fill in each square with the gene from
   the father.
5. Fill in each square with the gene from the
   mother.
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       Phenotypes vs. Genotypes
• The genotype is the specific genetic
  makeup (BB,Bb,or bb) of an individual, in
  the form of DNA .
• The phenotype of an individual organism
  is either its total physical appearance or a
  specific manifestation of a trait, such as
  size, eye color, or behavior that varies
  between individuals.

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• In other words, genotype is the genetic
  combination and phenotype is what it
  looks like.




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                    Assignment
• Complete worksheets 3-5 & 3-6.
• Complete Study guide 11-2
• Bikini Bottom Genetics




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                    Warm Up
•     Show a Punnett square that would result
      from the cross TT x tt. What would the
      genotypes and phenotypes of the
      offspring be?




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         How Well does a Punnett
         Square Predict the Actual
                 Ratios?
• Work with a partner to complete the
  punnett square lab




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                    Assignment
• Complete bikini bottom genetics 2 sheet




November 30, 2010                           135
                    Warm Up
• In rabbits, the allele for black fur is
  dominant over the allele for brown fur.
• A heterozygous black rabbit is crossed
  with a homozygous brown rabbit.
• Predict the possible genotypes and
  phenotypes of their offspring.
• Use a Punnett square to show your
  results.

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    What are incomplete dominance
          and codominance?




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             Incomplete dominance
• Incomplete dominance – offspring show a
  blending of traits from parent to parent.
• Neither allele is completely dominant over
  the other.




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                    Codominance
• Codominance – both alleles of a certain
  trait appear in the offspring.
• Neither allele is dominant over the other.
• Codominance does not involve blending.




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• Codominant and incomplete dominant
  crosses are sometimes shown with all
  capital letters. This shows that no
  particular trait is dominant over the other.




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             Heterozygous crosses
• Recessive genes do not disappear
• They show up when heterozygous
  organisms are mated




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• If 2 heterozygous black and white
  chickens are mated – there will be a 25%
  chance of an offspring being BB.
• There will be a 50% chance of an offspring
  being BW
• There will be a 25%chance of an offspring
  being WW.
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                    Assignment
• Complete bikini bottom incomplete
  dominance
• Complete practice: codominance and
  incomplete dominance
• Complete genetics with a smile lab
• Complete worksheet 3-7



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                    Warm up
• In some horses, the allele for white hair ,
  W, is codominant with the allele for red
  hair, R.
• What is the chance of offspring with only
  red hair resulting from a cross between
  two heterozygous parents?
• Draw a Punnett square to show your
  results.
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     How is Gender Determined?
• All humans have 23 pairs of
  chromosomes.
• In males, the 23rd pair of chromosomes is
  not alike.
• Male cells have one x chromosome and
  one y chromosome.
• The y chromosome is smaller than the x
  chromosome
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• Female cells have two x chromosomes in
  the 23rd pair.
• The x and y chromosomes determine the
  gender of an organism.
• Gender is the sex of an organism.




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                    Gametes
                    • Male cells have an XY pair
                      of chromosomes.
                    • During Meiosis, each
                      sperm cell receives only
                      one chromosome from
                      each pair.
                    • Every sperm cell contains
                      either an x or a y
                      chromosome.
November 30, 2010                             149
                    • Female cells have an
                      XX Pair of
                      chromosomes.
                    • During meiosis, each
                      egg cell receives one
                      chromosome from each
                      pair.
                    • All egg cells contain
                      only X chromosomes.
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                    Gender of Offspring
• The gender of offspring is
  controlled by the
  chromosome in the sperm
  cell.
• All children inherit their
  gender from their fathers.



November 30, 2010                         151
                    • If the sperm is carrying an
                      x chromosome, the
                      fertilized egg will have two
                      x chromosomes (xx) and
                      the baby will be a girl.




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• If the sperm is carrying
  a y chromosome, the
  fertilized egg will have
  one x chromosome and
  one y chromosome (XY)
  and the baby will be a
  boy.




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       What are sex-linked traits?
• Some traits are inherited along with
  gender
• These traits are controlled by the x and y
  chromosomes.
• Traits that are inherited along with gender
  are called sex-linked traits.



November 30, 2010                           154
                Sex-linked disorders
• Sex-linked disorders are more common in
  men, this is because sex-linked disorders
  are often recessive.
• Women have two x chromosomes, while
  one x chromosome might have the allele
  for a disorder, the other chromosome
  usually has a normal allele.
• Because the gene for the disorder is
  recessive, a female with each type of
  gene, still appears normal.
November 30, 2010                         155
• Colorblindness is a disorder in which a
  person cannot see the difference between
  certain colors.




November 30, 2010                        156
November 30, 2010   157
• Hemophilia is a disorder in which the
  blood does not clot properly




November 30, 2010                         158
                    Hemophilia
• Hemophilia is a sex linked
  disorder.
• A person with hemophilia
  lacks a special protein that
  allows blood to clot.
• Because it is a recessive
  trait, males generally have
  the disease, but females can
  be carriers.
November 30, 2010                159
  Duchenne muscular dystrophy
• Duchenne muscular
  dystrophy is a genetic
  disorder caused by an
  error in the dystrophin
  gene.
• The condition causes
  progressive muscle
  weakness as the muscle
  cells break down and die.

November 30, 2010             160
             Male Pattern Baldness




November 30, 2010                    161
                    Warm Up
•   Define the following terms:
•   Sex-linked
•   Gender
•   Gamete
•   Karyotype
•   Chromosomes
•   X-chromosome
•   Y-chromosome
November 30, 2010                 162
                    Carriers
• Women who have normal gene and one
  gene for a sex-linked disorder are said to
  be carriers.
• They can pass the gene along to their
  children.




November 30, 2010                              163
                    Pedigrees
• Scientists study the traits of past
  generations in order to predict the traits of
  the offspring.
• They do this by making a chart, called a
  pedigree, that is similar to a family tree.
• Pedigrees show how certain traits are
  passed down from generation to
  generation.
November 30, 2010                             164
• A pedigree
  chart is a
  chart which
  tells one all
  of the
  known
  phenotypes
  for an
  organism
  and its
  ancestors.




 November 30, 2010   165
• Inbreeding or reproducing with members
  of your bloodline increases the risk of
  genetic abnormalities.
• Inbreeding has caused many breeds of
  dogs to have harmful genetic traits.
  Dalmatians are often deaf, and other dog
  breeds have high frequencies of epilepsy,
  blindness, and hip displaysia.
• It is true, that mutts are often hardier and
  have less health problems.

November 30, 2010                            166
           The Story of Hemophilia
• Late in the summer of 1818, a human sperm
  and egg united to form a human zygote. One of
  those gametes, we don't know which, was
  carrying a newly mutated gene. A single point
  mutation in a nucleotide sequence coding for a
  particular amino acid in a protein essential for
  blood clotting. The zygote became Queen
  Victoria of England and the new mutation was
  for hemophilia, bleeder's disease, carried on the
  X chromosome.
November 30, 2010                                167
November 30, 2010   168
• Animal Pedigrees




November 30, 2010    169
                    Assignment
• Complete worksheets 3-9.
• Complete Pedigree chart
• Complete ancestors pedigree chart – use
  the information to create a pedigree chart
  using symbols, showing you and your
  siblings , your parents, grand parent, etc.



November 30, 2010                           170
                           Warm Up

• . The bison herd on Konza Prairie has begun to
  show a genetic defect. Some of the males have
  a condition known as "rabbit hock" in which the
  knee of the back leg is malformed slightly. This
  trait is a sex-linked gene and that is recessive.
  Now, suppose that the herd bull (the dominant
  one which does most of the breeding) who is
  normal (XN) mates with a cow that is a carrier for
  rabbit hock. What are his chances of producing
  a normal son?
November 30, 2010                                 171
1. If he mates with this cow every year,
   what percentage of their daughters have
   normal knees?
2. What percentage of their daughters will
   be carriers of rabbit hock?




November 30, 2010                        172
•     A woman with red-green color-blindness has a mother
      with normal vision. Knowing that color-blindness is a
      sex-linked recessive gene, can you determine what
      her father's phenotype is?
1.
      The woman marries a man with normal vision. What is
      the probability they will have sons who are red-green
      color-blind?

2.    What is the probability they will have daughters who
      are red-green color-blind?




November 30, 2010                                            173
•  A rancher owns a bull with many desirable
   characteristics. Unfortunately, he also has a sex-linked
   trait that in the recessive form leads to no pigment
   formation in the iris of the eye. This makes the bull very
   sensitive to sunlight and could lead to blindness. The
   rancher wishes to breed him to a cow that will minimize
   the chances of any offspring showing this trait. She
   would especially like to produce another bull with most
   of his sire's desirable qualities but without the
   nonpigmented eye. Two cows with the dominant normal
   colored eyes (XN) are available that have been
   genetically typed for this particular trait. Cow 1 has a
   genotype of XN XN and cow 2 is XNXn. Which of these
   two cows should the rancher choose as a mate to her
   bull if she wishes to minimize the occurrence of the
   nonpigmented eye in his offspring?
1. What percentage of the male offspring from the
   preferred cross will have nonpigmented eyes?

November 30, 2010                                          174
                    Assignment
• Complete Genetic smiley face lab in class.
  Hand in by the end of the period.
• Review text sections 14-1 and 14-2.
• Complete section review worksheets 14-1
  and 14-2.




November 30, 2010                         175
                    Warm up
•  Answer the following questions using
   complete sentences.
1. How can a female have the sex linked
   disorder of hemophilia? Use a Punnett
   square to explain your answer.
2. What kind of gene pair is found in the
   female carrier of a sex-linked disorder?


November 30, 2010                             176
          What are some inherited
                diseases?
• Abnormal genes are sometimes passed
  from the parents to their offspring,
• A disease caused by an abnormal gene is
  called an inherited disease.




November 30, 2010                       177
                    Sickle Cell Anemia
• Sickle cell anemia is an
  inherited disease that
  mainly affects people of
  African descent.
• The red blood cells of a
  person with sickle cell
  anemia are crescent
  shaped

November 30, 2010                        178
• Sickle cells get easily trapped in blood
  vessels.
• They clog blood vessels and block the flow
  of blood
• The clogged blood vessels may cause
  severe pain, and in some cases death.




November 30, 2010                         179
• The gene for sickle cell is recessive (s).
• Normal red blood cells are dominant (S).
• People who inherit 2 recessive genes
  have the disease (ss).
• People who inherit one recessive gene are
  carriers of the disease (Ss).




November 30, 2010                         180
                    PKU
• Phenylketonuria, or PKU, is another kind of
  inherited disease caused by a recessive
  gene.
• People with PKU are missing an important
  enzyme that is needed to break down the
  amino acid , phenylalanine.



November 30, 2010                          181
                    • People with PKU
                      cannot eat certain
                      protein-rich foods
                      such as meats,
                      eggs, cheese and
                      milk.
                    • If people who have
                      PKU do not follow
                      their diet carefully,
                      the amino acid may
                      build up in the body
                      and cause brain
                      damage or mental
                      retardation.
November 30, 2010                             182
                    Tay-Sachs Disease
• Tay Sachs is a disease that affects mainly
  Jewish children with Eastern European ancestry.
• An abnormal gene stops the child‘s body from
  producing an enzyme that breaks down fat.
• The fat gathers in the brain cells.
• This can cause brain damage and death.
• Most children with this disease die before their
  4th birthday.


November 30, 2010                               183
• A baby with Tay-Sachs disease appears
  normal at birth, but development starts to
  slow down at about 6 months of age.
  Gradually, the child becomes blind, deaf
  and paralyzed.
• The gene for Tay-Sachs is recessive.
• A person who is homozygous recessive
  (tt) inherits the disease.
• A person who is heterozygous (Tt) is a
  carrier.
November 30, 2010                              184
               Huntington‘s disease
• Huntington‘s disease is caused by a
  dominant gene.
• The gene prevents the brain cells from
  functioning properly.
• The symptoms include loss of muscle
  control, mental illness, and death at an
  early age.
• Most people with this disease do not know
  they have it until they have already passed
  the gene onto their offspring.
November 30, 2010                          185
                    Genetic counseling
• Genetic counselors study family histories
  and interpret test results in order to predict
  the possible traits of offspring.
• Genetic counselors provide pregnant
  women with the information about their
  risk of having a baby with a genetic
  disorder.
• They also counsel children and adults
  about their own chances of developing a
  disease.
November 30, 2010                             186
                    Assignment
• Study guide 14-3
• Complete worksheet 3-10.
• Complete sickle cell article and questions.




November 30, 2010                           187
                    Warm up
• Read ―Tigers‖
• Finish article and questions




November 30, 2010                188
   Conditions in the Environment
• The environment can change the way a
  trait is expressed.
• Heavy winds can cause trees to bend as
  they grow. Poor soil can cause plants to
  grow smaller than usual. These are called
  environmental influences.
• The environment can cause mutations in
  genes.
November 30, 2010                         189
            Environment and Traits




• The divi divi tree grows sideways because
  of the strong winds on the island of Aruba.

November 30, 2010                           190
                    Genetic Mutations
• A mutation is a change to the genetic
  material of an organism.
• A mutation can be harmful if it decreases
  the organisms ability to function properly.
• If the mutation occurs in the gametes of an
  organism, it can be passed on to the
  offspring.
• If the mutation only affects the body cells,
  the mutation is not usually passed on.
• Mutations can affect the single gene or the
  whole chromosome.
November 30, 2010                           191
                    Genetic Mutations




November 30, 2010                       192
November 30, 2010   193
                    Meningomyelocele




November 30, 2010                      194
                    Cleft lip




November 30, 2010               195
                    Webbed Toe




November 30, 2010                196
                    Progeria




November 30, 2010              197
November 30, 2010   198
                    Spina Bifeda




November 30, 2010                  199
                    Albinism




November 30, 2010              200
                    Marfan Syndrome




November 30, 2010                     201
  Dystrophic Epidermolysis Bullosa




November 30, 2010                202
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November 30, 2010   208
• The clouded leopard, which makes its home on
  the Southeast Asian island of Borneo, was
  discovered to be a unique species. It is the
  island's largest predator.
November 30, 2010                            209
                    Assignment
• Complete worksheet 3-11
• Complete a painful decision
• Complete study guide 12-4




November 30, 2010                210
                    Warm up
•  Answer the following question using
   complete sentences
1. Suppose a divi-divi tree was planted in a
   location with very little wind. What do you
   think it would look like?




November 30, 2010                           211
                Controlled Breeding
• Mating organisms to produce offspring
  with certain traits is called controlled
  breeding.
• The offspring usually have the same
  desirable traits as their parents.
• Controlled breeding is used with livestock
  and plants.


November 30, 2010                          212
                    Mass selection
• In mass selection, plants with desirable
  traits are crossed.
• Seeds produced by the plants are
  collected and planted. New plants develop
  from these seeds.
• If the new plants have the desirable traits,
  then their seeds are collected and planted.
• The process goes on and on and
  eventually you will get a new kind of plant
  with desirable traits.
November 30, 2010                           213
• Mass selection is used to produce larger,
  more succulent strawberries.




November 30, 2010                             214
                    Hybridization
• Sometimes two organisms with different
  kinds of genes are crossed. The offspring
  show traits of both parents.
• The mating of different kinds of organisms
  is called hybridization.
• For example, wheat and rye plants can be
  crossed to create triticale, which is more
  nutritious then either wheat or rye.
November 30, 2010                          215
                    • A mule is a result
                      of hybridization.
                    • Its father is a
                      donkey and its
                      mother is a horse.
                    • Mules are sterile
                      and cannot
                      produced their
                      own offspring.


November 30, 2010                     216
                             ligers
                    • Ligers are prone to
                      gigantism; they are the
                      largest cats in the
                      world and can be
                      double the size of an
                      average adult Siberian
                      tiger.



November 30, 2010                           217
November 30, 2010   218
November 30, 2010   219
       Tigon
• from a male tiger
  and a female lion




November 30, 2010     220
                    Savannah




• from a domestic cat or Bengal cat and a
  serval


November 30, 2010                           221
             Coywolf
• from a coyote
  and a wolf -
  although rare, it
  can happen in
  the wild




November 30, 2010      222
                    Wolf Dog
• Happens often
  because dogs and
  wolves breed freely
• Their jaws are much
  stronger than those of
  a dog and are often
  used to exert
  dominance.


November 30, 2010              223
                    Iron Age pig
                          • Domestic Tamworth pigs
                            are crossbred with wild
                            boar to create ‗Iron Age
                            Pigs‘.
                          • The hybrids are tamer
                            than wild boar and
                            generally become
                            specialist pork sausages.
                          • Most of them are bred for
                            the specialist meat trade.


November 30, 2010                                   224
                      Zorse




   • A zorse is the result of crossbreeding a
     horse and a zebra.
November 30, 2010                               225
                    Zonkey
                             • A zonkey is the
                               result of
                               crossbreeding
                               a donkey with
                               a zebra.




November 30, 2010                           226
                      Zony
   • The Zony is the result of crossbreeding a pony
     to a zebra.




November 30, 2010                                227
                    Cama
• A Cama is a hybrid between a camel and a
  llama.
• They are born via artificial insemination due to
  the huge difference in sizes of the animals which
  disallow natural breeding.
• A Cama usually has the short ears and long tails
  of a camel but the cloven hooves of a llama.
• Also most noticeably is the absence of the
  hump.

November 30, 2010                                228
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November 30, 2010   230
                    grolar/pizzly
• A grolar/pizzly hybrid is the product of a grizzly
  bear and a polar bear.
• Although the two bears are genetically similar,
  they tend to avoid each other in the wild.




November 30, 2010                                      231
                    Leopon

                       • A Leopon is the result
                         of breeding a male
                         leopard and a female
                         lion.
                       • The head of the
                         animal is similar to
                         that of a lion while the
                         rest of the bodies
                         carries similarities to
                         leopards.
November 30, 2010                              232
                    Hybrid Pheasant




November 30, 2010                     233
November 30, 2010   234
                    Inbreeding
• Inbreeding is the mating of closely related
  organisms
• Offspring produced by inbreeding have
  genes that are very similar to their parent‘s
  genes.




November 30, 2010                            235
• Inbreeding is used to breed racehorses,
  whose desirable trait is speed.
• Inbreeding is done only with animals with
  desirable traits.


November 30, 2010                             236
    Why inbreeding is not allowed in
             most states




November 30, 2010                      237
• Mammals, most other animals, and higher
  plants as well, have evolved mechanisms
  to avoid inbreeding of any sort.
• Most pack animals (like lions, primates,
  and dogs), kick young males out of the
  pack so as to prevent them from mating
  with female relatives.




November 30, 2010                        238
                    Animal Breeding
• Animal Breeders study the genes that
  control certain traits in animals.
• They use this info to breed animals and
  produce offspring with desirable traits.
• For example, a thoroughbred race horse is
  bred for speed. A workhorse is bred for
  strength. A showhorse is bred for their
  ability to jump.

November 30, 2010                        239
                    Assignment
• Complete worksheet 3-12.
• Read genetic testing article.
• Create a written outline of the information
  in the article.
• Answer discussion questions ( counts as a
  quiz grade)



November 30, 2010                          240
                    Warm up
•  Answer the following questions using
   complete sentences.
1. Define mass selection, hybridization and
   inbreeding.
2. Why is inbreeding dangerous to an
   organism?
3. Would you rather have an inbred dog or
   a hybrid dog as a pet? Explain.

November 30, 2010                         241
                    Warm up
• If a genetic disorder were present in your
  family, would you go to a genetic
  counselor before having children? Why or
  why not?




November 30, 2010                          242
                Genetic engineering
                            • Genetic
                              engineering is
                              the process by
                              which new
                              forms of DNA
                              are produced.



November 30, 2010                              243
                    Gene Splicing
• Gene splicing is a process in which a
  section of DNA from one organisms is
  transferred to the DNA of another
  organism.




November 30, 2010                         244
  Gene Splicing creates a new DNA
               strand




November 30, 2010               245
           3 steps of gene splicing
                     1. Dna ring is
                        temporarily opened
                        using certain
                        specific enzymes.
                     2. New genes from
                        another organism
                        are added, or
                        spliced, into the
                        DNA
                     3. The DNA ring is
                        closed.
November 30, 2010                        246
November 30, 2010   247
                    Benefits
1. Using gene splicing, bacteria can be
   used to manufacture human insulin.
2. Potential cures for genetic disorders
3. Improve traits in certain plants and
   animals used for food.




November 30, 2010                          248
                    • Scientists have
                      discovered a gene
                      that makes
                      corn resistant to
                      certain damaging
                      insects.



November 30, 2010                         249
• Thanks to genetic engineering, North Carolina
  soybeans can now be sprayed with Roundup,
  making weed control easier, less expensive, and
  safer for the environment.


November 30, 2010                              250
                    Disadvantages
1. Experimenting with bacterial DNA may
   cause a disease for which there is no
   cure.




November 30, 2010                          251
• Will we create
  things that look
  like this?




November 30, 2010    252
November 30, 2010   253
                    Cloning
• Cloning is the production of cells or organisms
  with identical traits.
• One way of cloning is to take the nucleus out of
  a cell from a donor animal.
• Then place the nucleus into an egg cell whose
  own nucleus has been removed.
• Then place the egg cell in the uterus of an
  animal and allow it to develop.
• When the baby animal is born, it is identical to
  the donor animal.

November 30, 2010                                254
• Dolly, the first cloned
  sheep, was identical to
  her mother.
   November 30, 2010        255
• Clones can occur naturally in nature, a
  process called twinning. Identical twins
  are, in fact, clones.




November 30, 2010                            256
 What is the purpose of cloning?
• 1. Cloning for medical purposes
  2. Cloning animal models of disease
  3. Cloning stem cells
  4. Cloned genetically engineered animals
  for drug production
  5. Reviving endangered or extinct species
  6. Reproducing a deceased pet or child


November 30, 2010                         257
• Scientists often clone bacteria to make
  drugs.
• Cloning can also help produce animals
  with desirable traits.
• Scientists use cloned animals to study
  diseases.




November 30, 2010                           258
                    Assignment
•   Complete worksheet 3-13
•   Study guide 13-4
•   Complete section review 13-4
•   Complete genetic engineering enrichment




November 30, 2010                         259
                    Warm Up
• Solve the following problems
• In humans, the genes for colorblindness and
  hemophilia are both located on the X
  chromosome with no corresponding gene on the
  Y. These are both recessive alleles. If a man
  and a woman, both with normal vision, marry
  and have a colorblind son, draw the Punnett
  square that illustrates this. How many/what
  percentage of each could be expected?

November 30, 2010                            260
                    Cloning Humans
• Read the article ―South Korean Scientists
  Say they Cloned a Human Cell‖
• Answer the questions that follow in
  complete sentences.
• Be prepared to share.




November 30, 2010                         261
                    Homework
• Study for test tomorrow




November 30, 2010              262

								
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