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Section Outline
Section 13-1
131 Changing the Living World A. Selective
Breeding 1. Hybridization 2. Inbreeding B. Increas
ing Variation 1. Producing New Kinds of
Bacteria 2. Producing New Kinds of Plants
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Selective Breeding

• For centuries, humans have chosen desirable
  traits for dog breeding. This type of trait
  selection is called selective breeding.
• There are two types of selective breeding
• Hybridization
• 2.Inbreeding

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Hybridization

• Luther Burbank (1849-1926) is deemed as one of
  the greatest selective breeders. He developed
  disease- resistant potatoes as well as many other
  varieties in plants.
• Burbank often crossed different individuals to
  bring together the best of each organism. This
  is called hybridization.
• Ex. Disease resistance x high food-producer

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pictures
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Inbreeding

• Risky business Inbreeding causes individuals
  to be genetically similar, thus increasing the
  chances of bringing two recessive alleles
  together. ( Ex. Blindness in German Shepherds.)
• After the desired qualities are established, many
  breeders then inbreed or continue to breed
  individuals together with similar characteristics.

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Manipulating DNA

• In the past, scientists had to rely on variation
  (natural and mutation generated) to produce
  changes in DNA.
• Now, scientists can change DNA because
• Structure of DNA is known
• Able to cut, extract and transfer pieces of DNA
• Make unlimited copies of DNA

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Genetic Engineering

• Making changes in the DNA code of a living
  organism.
• 3 Basic Steps
• DNA extraction
• Cutting DNA
• Separating DNA

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Cell transformation the Big Picture!

• During transformation, a cell takes in DNA from
  outside the cell. (manipulated?)
• This external DNA becomes part of the cells
  DNA.
• Ex. Griffiths pneumonia experiments.

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Concept Map
Section 13-1
Selective Breeding
consists of
which crosses
which crosses
for example
for example
which
which
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Transgenic Organisms

• Transgenic organisms contain genes from other
  organisms. (ex Firefly glow gene inserted
  into tobacco plant)
• Biotechnology- new industry resulting from
  genetic engineering.

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Transgenic Microorganisms

• Transgenic bacteria are used to produce many
  useful substances for health and industry.
• Why bacteria?
• 1. Reproduce quickly 2. Easy to grow
• Examples
• Human proteins cheap and abundant
• Human insulin

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Transgenic Animals

• Used to study genes
• Ex. Mice with immune systems like humans-gt study
  diseases
• Improve the food supply
• Ex. Livestock with growth hormone-gt faster
  growing and less fatty meat
• Future? animals that produce human proteins.

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New type of cat
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Transgenic Plants

• Important part of food supply.
• Ex. Many contain genes that produce a natural
  insecticide. No need for synthetic pesticides.
• Ex. Rice with added vitamin A.

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Cloning

• A clone is a member of a population of
  genetically identical cells produced from a
  single cell.
• 1997- Dolly was cloned in Scotland by Ian
  Wilmut.
• In the news today Cloned embryos okayed in
  Scotland.

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Flowchart
Cloning
Section 13-4
A body cell is taken from a donor animal.
An egg cell is taken from a donor animal.
The nucleus is removed from the egg.
The body cell and egg are fused by electric shock.
The fused cell begins dividing, becoming an
embryo.
The embryo is implanted into the uterus of a
foster mother.
The embryo develops into a cloned animal.
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Figure 13-13 Cloning of the First Mammal
Section 13-4
A donor cell is taken from a sheeps udder.
Donor Nucleus
These two cells are fused using an electric shock.
Fused Cell
Egg Cell
The nucleus of the egg cell is removed.
An egg cell is taken from an adult female sheep.
The fused cell begins dividing normally.
Embryo
Cloned Lamb
The embryo is placed in the uterus of a foster
mother.
The embryo develops normally into a lambDolly
Foster Mother
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