Bell Work: 2/28/13

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Bell Work 2/28/13
Work out the Punnett square JUSTIFY YOUR
ANSWER!!!
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Objectives

• Classify methods of reproduction as sexual or
  asexual. (SPI 0707.4.1)
• 63. Asexual vs. Sexual Reproduction

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Determining the Sex or Gender of Offspring

• Sex chromosomes carry genes that determine the
  sex or gender of offspring.
• In humans, females have two X chromosomes and
  males have one X and one Y chromosome.
• During meiosis, one of each of the chromosome
  pairs ends up in a sex cell.

• Baby boy XY
• Baby girl XX
• Set up a Punnett square to figure out the
  probability of the gender of the offspring.

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Sex Chromosome Probability
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Sex ChromosomeChromosome 23 (XX or XY)
xx
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Living Things Reproduce

• 2 Types of Reproduction
• Asexual- a single parent produces an offspring
  identical to the parent
• Sexual- two parents produce an offspring with
  traits of both parents

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Challenge Questions

• When animals go through sexual reproduction, what
  type of cell division are they going through?
• meiosis
• When animals go through asexual reproduction,
  what type of cell division are they going
  through?
• mitosis

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Types of Asexual Reproduction In Animals

• Budding happens when a part of the parent
  organism pinches off and forms a new organism.
• The new organism separates from the parent and
  lives independently.
• Jellyfish hydra

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Types of Asexual Reproduction In Animals

• Fragmentation parts of the organism break off
  and a new organism grows identical to the parent.
  
• Worms starfish

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Types of Asexual Reproduction In Animals

• Regeneration organism loses a body part and that
  part may develop into a new organism.
• Sea star

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Asexual Reproduction in Other Organisms

• Binary fission is a method of asexual
  reproduction in which an organism splits into
  two.
• This occurs in bacteria and other single-celled
  organisms

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Asexual Reproduction in Plants

• Some plants can reproduce asexually when they are
  cut or damaged. These plants can sprout new
  growth from their roots, stems, and leaves.
• In wild strawberry plants, stems are capable of
  arching downward and taking root in the ground,
  resulting in the formation of a new plant. This
  is an example of asexual reproduction.

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Be ready to justify your answer!
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Scenario Stations

• Number a loose-leaf sheet of notebook paper (in
  the numbered folder at your group) 1-16, skipping
  two lines in between each number.
• At each station there are two scenarios
  (real-world examples) of either sexual or asexual
  reproduction.
• You and your group will have 2 minutes at each
  station to do the following
• Classify each method of reproduction in the
  scenario as sexual or asexual reproduction.
• Justify your answer.
• The scenarios at Station 8 (lab table 8) will be
  for extra credit, but it is mandatory that you
  try them!
• We will discuss these either at the end of class
  or first thing tomorrow.
• When you are finished, you will complete an exit
  ticket comparing and contrasting sexual vs.
  asexual reproduction.

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Exit TicketCompare Contrast Sexual vs.
Asexual Reproduction using a Venn diagram.
Sexual Reproduction
Asexual Reproduction