Chapter 13 Biotechnology 2013

gooseliverBiotechnology

Oct 22, 2013 (3 years and 7 months ago)

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CP BIOTECHNOLOGY

CHAPTER 13

13.1 What is biotechnology?

The use of organisms to


perform practical tasks

for humans


13.1 Biologists Manipulate DNA



Today, we mainly manipulate the genomes of
organisms.



We called this act of manipulation
DNA technology.

13.1 Bacteria


Commonly used in
Biotechnology

* because they can acquire new
genes in many ways!


1.

Tunnel
-
like structure

forms
between 2 bacteria so DNA
can be passed
-
Conjugation


2.
Transformation



bacteria
can “take up” free floating
DNA into their own DNA


3. Viruses can carry bacterial
genes from one bacteria to
another
-

transduction.


13.1 Recombinant DNA Technology

Definition

-

technology involving the combining of DNA
and/or genes from different sources (even genes
from different species).



Uses of DNA technology:

1.
Make more nutritious crops (ex. Corn)

2.
Make medicine in large quantities

3.
Help us understand specifically how gene sequences
work

13.2 Engineering Bacteria


Bacteria contain plasmids


Plasmids are small circular pieces of DNA separate
from the bacterial chromosome.


Plasmids carry genes


13.2 Plasmids


Scientists can manipulate plasmids to make them
useful to us and Bacteria can transfer plasmids!!




Example:


1.
Insert a gene to make a medicine into a plasmid

2.
Put the plasmid into bacteria

3.
When the bacteria reproduce they make many
copies of the medicine!

Process of Making Recombinant Bacterial Cell

13.2 How Do They Do It???

1.
Cut


Use
restriction enzymes

to cut the
desired DNA/gene out of a larger
chromosome


2.
Paste


Put the desired DNA/gene fragment
into a plasmid


3.
Put the plasmid into a bacterium


4.
As the bacterium reproduces it
makes many copies of the desired
gene!! (Page 270 Case Study)


Restriction
Enzyme=scissors

13.2

Genomic Library & Nucleic Acid Probes


Genomic Library:
the complete
collection of cloned DNA
fragments from an organism





Nucleic Acid Probe
:
complimentary nucleotides
labeled with a radioactive
isotope used to “tag” single
strand of a DNA sequence of
choice.

13.2 FYI: Useful Products Using Genetic
Engineering

1.
Bacteria make chemicals that clean up hazardous spills
and toxic waste sites

2.
Bacteria are mass
-
producing useful chemicals like
pesticides and therapeutic drugs

3.
Pigs & Cattle make human insulin hormone in their milk
for people with diabetes





4.
Recombinant DNA technology is used to develop
Vaccines


Hepatitis B (viral proteins are massed
produced in yeast cells then used in vaccines)

13.3 Genetically Modified Organisms


A
genetically modified organism (GMO)

is any
organism that has acquired any genes artificially.



If a species is called
TRANSGENIC

if it has foreign
genetic material from a different species.

13.3 Genetically Modified

Plants

Do you eat genetically modified organisms?


YES





NO

Just a few…GMO FOODS


Honey


Cotton


Tomatoes


Corn


Vegetable Oil


Peas


Potatoes




Warm
-
Up
-

In Groups…


½ the class will use their books to compile a list of
postive or good reasons/outcomes of using
genetically modified organisms (plants and animals)



½ the class will use their books to make a list of
negative or unwanted reasons to use genetically
modified organisms.

Here’s what YOU think…


13.3 Genetically Modified

Plants


Over 50% of soybean and corn crops were
genetically modified in some way!



Most common genetic modifications:


Genes for herbicide resistance


Genes to resist insect and fungi pests


13.3 Genetically Modified
Animals


Goals for GMO animals…


Produce mass quantities of hormones (insulin)


Get animals to market quicker (salmon)


Breed animals with better quality products (sheep wool)


FUN!! $$$$$$$

Few more
examples…

13.3 The GMO Controversy


Although studies to date have shown that eating
genetically modified foods have no negative health
affects…people continue to demand stricter
regulations.



Major Concern:

GMO food can pose unknown health risk…request strict
labeling laws


**”ORGANIC CRAZE”**

13.3 GMO Controversy

13.4 DNA Tech Has Many Applications


PCR or Polymerase Chain
Reaction

technique can
mass produce specific
sequences of DNA without
the use of living cells


Takes less time than use
of living cells


Requires less amount of
desired DNA initially


Used for cloning rare
DNA & ID small amounts
of infectious DNA (AIDS)

Thermocycler
-

machine used
for PCR

13.4 PCR Technique

“make a lot of DNA”
from a small sample

Page 278 figure 13
-
15

13.4 Gel Electrophoresis


Used when you want to compare DNA from
different sources.


Produces “banding patterns” which can be
compared and analyzed.

13.4 Comparing DNA: How it works!
(Pg 279)

2.DNA “fragments” move
through gel using electric
current.

Smaller DNA
fragments
move further

1.Different DNA
samples are cut into
“fragments” by
restriction enzymes

Each sample produces
different banding
patterns in the gel so
they are easily
compared

13.4 Comparing DNA: Genetic Markers


Genetic Markers: are
particular streches of
DN that are variable
among individuals.


Can be used to ID
carriers of certain
diseases

13.4 Comparing DNA:
DNA

Fingerprint


Just like every person has their own unique
fingerprint…everyone has a unique banding pattern
produced by their restriction fragments in gel
electrophoresis.



97% of our DNA is “junk” or non
-
coding and is
extremely different from any other persons “junk” DNA.



Forensics!!

13.4 Who committed the crime?

Bloodstain
evidence from crime scene!

Suspect #


1 2 3 4 5 6 7

Using PCR and Gel
Electrophoresis, a DNA
fingerprint can be made
from a single drop of blood
or from a hair follicle.

DNA is extracted from a
small sample and
multiple copies are made
using PCR

Gel Electrophoresis of
unique genetic markers are
compared

13.5 Stem Cells and Homeotic Genes


Stem cells



cells (early in
development) that remain
undifferentiated and have the
potential to be any type of
cell.



Homeotic Genes



genes that
control development of specific
locations in organisms.

Cloning


To make a clone:


A donor cell is fused with an egg
cell


The fused cell begins to divide
normally to form an embryo


Embryo is placed in uterus of foster
mom


Clone is born

Cloning