Transcript Lesson Overview

Lesson Overview
Meeting Ecological Challenges
Chapter 15
Genetic
Engineering
15.1
Selective
Breeding
Lesson Overview
Meeting Ecological Challenges
Selective Breeding
•
only organisms with
–
characteristics reproduce.
• Two Types
o
o
Lesson Overview
Meeting Ecological Challenges
Hybridization
• Hybridization - crossing
individuals to mix best of both.
• Hybrids are often
•
•
than the parents.
Ex: Crossing disease-resistant plants with productive
plants.
Ex: Horse + donkey = mule
Lesson Overview
Meeting Ecological Challenges
Inbreeding
•
- breeding individuals with
characteristics.
– Adv:
characteristics
– Disadv: Increases chances for
genetic
.
Copyright Pearson Prentice Hall
Lesson Overview
Meeting Ecological Challenges
Increasing Variation
•
– using
technological processes on living organisms.
•
breeding is one form
of biotechnology important in agriculture and
medicine, but there are many others.
Lesson Overview
Meeting Ecological Challenges
Increasing Variation
• Breeders can increase genetic variation by
introducing
.
• Ex: Oil-digesting bacteria
•
(
sets of chromosomes) plants
are larger and stronger than their diploid
relatives.
Copyright Pearson Prentice Hall
Lesson Overview
Meeting Ecological Challenges
15.1 Review
1. What are the two types of selective breeding?
2. What is the difference between the two types?
3. What are two ways to increase variation?
4. What does “polyploidy” mean?
Lesson Overview
Meeting Ecological Challenges
Chapter 15
Genetic
Engineering
15.2
Recombinant
DNA
Lesson Overview
Meeting Ecological Challenges
THINK ABOUT IT
Suppose you have an electronic
game you want to change.
Knowing that the game depends
on a coded program in a computer microchip, you’d
need a way to get the existing program out of the
microchip, read the program, make the changes you
want, and put the modified code back into the
microchip.
What does this scenario have to do with genetic
engineering? Just about everything.
Lesson Overview
Meeting Ecological Challenges
Copying DNA
1. Extract DNA.
2.
Cut DNA into fragments.
enzymes –
3.
chain reaction (
used to copy DNA fragments.
)–
Lesson Overview
Meeting Ecological Challenges
Polymerase Chain Reaction
1.
DNA strands.
2. Add DNA
to make DNA copies.
3. Use copies to make
more copies.
Lesson Overview
Meeting Ecological Challenges
Combining DNA Fragments
• It can be beneficial to
DNA
from
different organisms.
•
–
A gene from one organism that is combined
with the DNA of another organism.
Lesson Overview
Meeting Ecological Challenges
Plasmids and Genetic Markers
• We can transform bacteria using
• Plasmids in bacteria.
circular
.
molecules
Lesson Overview
Meeting Ecological Challenges
Plasmids and Genetic Markers
•
marker –
a gene used to
only desired bacteria.
Lesson Overview
Meeting Ecological Challenges
Transgenic Organisms
– organism
.
containing genes from
-An organism with recombinant DNA
Lesson Overview
Meeting Ecological Challenges
Cloning
-a
identical copy
First clone - In 1997, Ian
Wilmut cloned a sheep
called Dolly.
Lesson Overview
Meeting Ecological Challenges
Cloning
Animal cloning uses a procedure called nuclear
transplantation.
1. Nucleus of egg is
2. Egg is
with
3. Egg is placed in foster
.
cell.
.
Lesson Overview
Meeting Ecological Challenges
15.2 Review
1. What do restriction enzymes do?
2. What is the process of copying DNA (abbrv.)?
3. When DNA from two different organisms is combined,
what is it called?
4. If we wanted to isolate specific bacteria, what would we
use?
Lesson Overview
Meeting Ecological Challenges
15.1/15.2 Review
Each group must pick one of the following to explain. One
person in each group must explain their topic:
A. What is selective breeding? What are the two types (and give
examples).
B. What are two ways breeders increase variation? Explain
them.
C. What are the three steps of copying DNA?
D. What are the three steps of PCR?
E. What are the three steps of cloning?
F. What is the difference between the terms “recombinant” and
“transgenic”?
Section 15-3:
Applications
of Genetic
Engineering
Chapter 15:
Genetic
Engineering
Agriculture and Industry
 Genetic



engineering could give us:
expensive food
nutritious food
manufacturing
GM Crops
“
”
 Crops
resistance to herbicides,
rot, and spoilage
GM Animals
milk, more meat, and leaner meat.
 Clone to
endangered species.

Treating Disease
 Use
to make
DNA
proteins
 Insulin,
blood-clotting
factor, cancer-fighting
proteins

–
changing a gene to
treat a medical disease.
Treating Disease
 Very
 Need
a more
to insert working genes
 Make sure it’s not
way
DNA Microarray
 Not
gene is active
 DNA
the time
–
measures activity level of genes
 Colored tags label source of DNA
 Red
spots = more
cancer mRNA
 Green
spots = more
normal mRNA
 Yellow
spots = both
Personal Identification

analyzes sections of
DNA with little/no
function, but that
vary widely.
–
Forensic Science

crime scene evidence
 Uses DNA fingerprinting to
crimes, overturn convictions
= study of
15.3 Review
1.
What does “GM” stand for? Name benefits.
2.
What is gene therapy?
3.
What measures gene activity?
4.
What does DNA fingerprinting look at?
5.
Why does DNA fingerprinting work?
Lesson Overview
16.1 Darwin’s Voyage
of Discovery
Darwin’s Epic Journey
– Developed scientific theory
explaining how organisms
evolved over long periods of
through descent
from
ancestors 
Darwin’s Epic Journey (cont.)
- Three distinctive patterns of diversity:
(1) Species vary
(2) Species vary
(3) Species vary
.
Species Vary Globally
- Different but
species live in
habitats around the globe.
• Rhea of SA
• Emu of Australia
• Ostrich of Africa
Species Vary Locally
- Different, yet related,
species occupy
different
within a
area.
- Ex: Galapagos Islands which
are close together but have
different ecological conditions
which lead to very distinct
giant tortoises.
Species Vary Locally (cont.)
– Ex. Darwin’s Finches
varied depending on their
structure
.
Species Vary Over Time
-
- preserved
remains of ancient
organisms.
- Some fossils were
to
species.
Putting the Pieces of the Puzzle Together
- The evidence suggested species could
by
process.
Review 16.1
1. What theory states organisms evolved over
time from a common ancestor?
2. What were three ways Darwin found species
vary?
3. Species can change by ________________
processes.
Lesson Overview
16.2 Ideas That Shaped
Darwin’s Thinking
An Ancient, Changing Earth
– Uniformitarianism Processes that changed
Earth in the
continue to operate in the
.
Lamarck’s Evolutionary Hypotheses
–
proposed
organisms change during their
lifetimes by
parts of their bodies.
• Acquired characteristics.
– Suggested these traits could be
on to offspring
• Inheritance of acquired
characteristics
Evaluating Lamarck’s Hypotheses
– Lamarck’s hypotheses were
.
– Evolution
species becomes “
”
– Acquired traits
be passed on
to offspring.
Artificial Selection
–
selection - nature provides
variations, but humans
to pass on.
– Breeders do this for animals and plants.
– Recognized
variation provided
raw materials for evolution.
Review 16.2
1. The process that changes Earth both in the past
and present is called…
2. Who’s ideas about evolution were incorrect?
3. Why were his ideas incorrect?
4. What is artificial selection?
Lesson Overview
16.3 Darwin Presents
His Case
When does natural selection
occur?
–
– Variation and
– Survival of the
for existence
The Struggle for Existence
– When more individuals are
than can survive,
members must
to
obtain food, living space, and other
necessities of life.
Variation and Adaptation
–
- Characteristic that
ability to survive.
• Ex: Camouflage, sharper claws, efficiency,
behaviors
Survival of the Fittest
–
– ability to survive and
in its environment.
• High fitness - Individuals well-suited to environment
and can reproduce
• Low fitness - Individuals not well-suited to environment
and die without reproducing or leave few offspring
–
of the
–
Individual with the highest fitness will survive.
Natural Selection
–
selection - organisms with
variations for the
environment survive.
–
—not breeder—influences fitness.
– Populations change as they become better adapted,
or as environment changes.
Natural Selection Example
1. Grasshoppers can lay 200 eggs at
a time, but
survive to
reproduce.
2. Variation includes yellow and green
body
.
 Which color is adaptation? Green
3. Green grasshoppers = higher
= survive & reproduce
4. Green grasshoppers more
common because higher fitness in
this
environment
Natural Selection
– Natural selection does not make
organisms “
.”
– Natural selection doesn’t move in
a
direction.
• Changes to fit environment.
• If organism cannot adapt, could go extinct.
Common Descent
– Evolution suggests
- all life descended from ancient common
ancestors.
–
–
living species descended, with modification, from
common ancestors.
Review 16.3
1. What three things happen for natural selection
to occur?
2. Characteristic that increases ability to survive…
3. What does fitness mean?
4. Natural selection can change based on the…
Lesson Overview
16.4 Evidence of Evolution
Biogeography
–
the
- study of where organisms live
and where their ancestors lived in
.
The Age of Earth
- Geologists use
dating to indicate that Earth is
about 4.5 billion years old.
Recent Fossil Finds
- Paleontologists have
discovered many
believed to be
stages.
Comparing Anatomy and
Embryology
– By Darwin’s time, scientists had noted that all
vertebrate limbs had the same
basic
.
Homologous and Analgous Structures
–
structures shared common
–
structures shared common
Ex: The wing of a bee
and wing of a bird
Homologous or Analogous??
Vestigial Structures
–
structures –
inherited structures with little to
.
• Ex: Wings of penguin, ostrich, etc.
– As scientists learn more, many parts thought to be
vestigial actual have function.
• Ex: Tonsils, coccyx
Embryology
– Embryos of
develop in
organisms
ways
• Used as evidence of common
ancestor.
Only so many ways to do the same thing.
Life’s Common Genetic Code
– All living cells use
coded in
– There are also homologous
.
.
• Some Hox genes are found in most multicellular animals
Review 16.4
1. Difference between homologous and analogous?
2. ___________________ fossils link past and
present organisms.
3. What is a vestigial structure?
4. All living cells use what for information?