Genetic Engineering

chemicalcaptionBiotechnology

Dec 16, 2012 (4 years and 9 months ago)

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Genetic
Engineering

Chapter 13

Changing the Living World


Selective breeding


Breeding animals with characteristics
we want to produce offspring with
those


Plants


Potatoes or flowers


Animals


dogs or farm animals



Hybridization


Cross different individuals to get offspring
with favorable traits


The result is a
hybrid



an individual
produced from the crossing of two different
organisms.


Inbreeding


Breed similar individuals over and over to
get offspring with favorable traits



Changing the Living World


Increasing variation


Inducing mutations


Radiation


Chemicals


Produce
mutants



an individual showing
the mutation


Producing new bacteria


Small size allows for millions to be
treated


Oil eating bacteria


Producing new plants


Chemicals that prevent chromosomal
separation


Polypoidy


Larger and stronger plants



13
-
2 Manipulating DNA


How can scientists manipulate
the code?


Scientists use their
knowledge of the
structure of DNA and its
chemical properties to
study and change DNA
molecules.

13
-
2 Manipulating DNA


Tools of Molecular Biology


Genetic Engineering


Making changes in the DNA
code of a living organism


DNA Extraction


Open a cell (mechanical and
chemical methods)


Use a chemical to separate the
DNA from the rest of the cell
parts (an alcohol)

13
-
2 Manipulating DNA

Cutting DNA

DNA molecules are very long

Restriction enzymes

Enzymes that cuts DNA at a specific sequence of nucleotides

Sticky ends



these are the cut ends of the DNA

13
-
2 Manipulating
DNA

Separating DNA

Gel electrophoresis

A
mixture of DNA
fragments is placed at
one end of a porous gel
(negative end), and an
electric voltage is
applied to the
gel. The
molecules will move
from negative to
positive

13
-
2 Manipulating DNA

13
-
2 Manipulating DNA

Using the DNA Sequence

Once it is separated it is manageable

It can now be

Read

Studied

Changed

13
-
2 Manipulating DNA


Reading the
Sequence


How do you read
unknown DNA?


You can use:


DNA Polymerase


Four nucleotides


Chemical markers


13
-
2 Manipulating DNA


Making Copies


PCR or Polymerase chain reaction


Photocopying DNA over and over


Use strands of DNA that are called
primers

Polymerase Chain
Reaction (PCR)

13
-
2 Manipulating DNA


Cutting
and
Pasting


DNA synthesizers


Enzymes join artificial
pieces of DNA with
natural pieces


Recombinant DNA


Enzymes join genes
from one strand of
DNA with genes from
another strand of
DNA


13
-
3 Cell Transformation


Transformation


When a cell takes in foreign DNA and joins it
with the existing DNA


This external DNA becomes part of the cells
DNA


Transforming Bacteria


Foreign DNA is joined to plasmid



Plasmid



small, circular DNA molecule


Genetic marker



a gene that makes it possible see
which bacteria are carrying the plasmid (that is
marked) and which bacteria are not.


Transforming Plant Cells


Using bacterium that normally infect plant cells and
cause tumors


Taking away the cell wall some plant cells will take
up DNA on their own


If successful recombinant DNA will be found in a
chromosome of the cell


13
-
3 Cell Transformation


Transforming Animal
Cells


DNA can be injected
directly into the nucleus
of an egg


Enzymes help insert the
new DNA into the eggs
with the existing
DNA


New DNA contains
markers that tell which
cells picked up the
DNA

13
-
4 Applications of Genetic
Engineering


Transgenic microorganisms


Bacteria reproduce quickly


Uses:


Can grow human proteins


Insulin, growth hormone, and
clotting factor



Transgenic Organisms


Organisms that contain genes
from other species


Firefly and tobacco plant


Genetic engineering has increased
the growth of
biotechnology


13
-
4 Applications of Genetic
Engineering


Transgenic Animals


Mimic human body for
testing


Faster growing animals


No more food poisoning


Grow human proteins


Transgenic Plants


Natural insecticide


Resist weed killing chemicals


Food resistant to spoiling


Weather resistant plants


Grow vitamins or proteins


13
-
4 Applications of Genetic
Engineering


Cloning



Clone
-

A member of a
population of genetically
identical cells produced from a
single cell


Dolly


The cloned sheep from
1997


Save endangered species