Transcript Chapter 5-3 - Mahtomedi Middle School

Chapter 5-3
Putting it all together for the
Advances in Genetics – where
are scientists going with all
this?
Three Methods people have use to
develop organisms with desirable
traits
 Selective breeding
 Inbreeding
 Hybridization
#2: Selective Breeding
 Process of selecting a few organisms
with the desired traits to serve as
parents of the next generation is
selective breeding
Selective Breeding continued
 This is selecting organisms with
desired traits to be parents of the
next generation
 This has been done for 1000’s of
years
Inbreeding:
3. Crossing two individuals that
have similar characteristics.
Inbreeding continued
 Example: cross two turkeys that are
plump and grow quickly
 Usually genetically very similar
 Can increase the probability that
organisms may inherit alleles that
lead to genetic disorders.
Inbreeding continued
a. Can increase the probability that
organisms may inherit alleles
that lead to genetic disorders.
Hybridization:
4. Crossing two individuals that are
genetically different
a. They are bred to have the best
traits from both parents
True or False
 In hybridization, breeders cross two
individuals that are genetically
identical.
 FALSE
 Why???? Hybridization crosses two
genetically different individuals
Question:
 When breeders cross two genetically
different individuals to produce an
organism with the best traits from
both parents, this breeding method is
called ________________
Answer:
 Hybridization
Clone
5. an organism that has exactly the
same genes as the organism
from which it was produced
Cloning: info
 Plants are easy to clone:
 cut a stem from one plant and put the
stem in soil, water it and it will grow into
a new plant…NOT ALL PLANTS will do
this, however!
Cloning in animals:
 More complex!!!
 Take the nucleus of an animal’s body
cell and use that to produce a new
animal by injecting the information
into an “empty” egg
 Discover video clip (8 minutes) –
Modern Genetics…more about cloning
What letters are true for #6?
a. A clone has exactly the same genes
as the organism from which it was
produced.
b. A cutting is one way to make a clone of an
animal.
c. It’s easier to clone an animal than it is to
clone a plant.
Answer:
A.
A clone has exactly the same
genes as the organism from
which it was produced.
True or False
 Cloning can be done only in animals.
False
Why? Cloning animals can be
done, it’s just more complex than
plants.
Genetic Engineering: #8
 Genes from one organism are
transferred into the DNA of another
organism
Genetic Engineering continued
 This is used for:
 Producing medicine and improving
food crops
Genetic Engineering, continued
 Human genes can be inserted into the
cells of cows so the cows produce the
human protein for milk
 Same technique used for producing
blood clotting protein needed by
people with hemophilia
 Allow plants to resist cold
temperatures
 Enable plants to resist insect pests
Using genetic engineering to fix
some genetic disorders in humans
 Gene Therapy - Inserting copies
of a gene directly into a person’s
cells
 Example: treat hemophilia by
replacing the defective allele on the X
chromosome
Concerns about Genetic
Engineering
 Are crops that have been genetic
engineered safe?
 Will they harm the environment or
cause health problems in humans?
 Will other genetic disorders be caused
by correcting one genetic disorder?
The Human Genome Project: #11 & 12
 Genome: All the DNA in one cell of
an organism.
Goal of the Human Genome Project
 Pinpoint the DNA sequence of
every gene on every chromosome
 DNA of humans has at least 30,000
genes and each gene is made up of at
least 30,000 bases
DNA Fingerprinting
 Identify people from their DNA
DNA Fingerprinting
 Show whether people are related
or not – useful for criminal
investigations
 No two people have the same DNA
EXCEPT for identical twins
HOW:
DNA from a
person’s cells
is broken down
into smaller
pieces. The
pieces are
used to
produce a
pattern
LOTS & LOTS OF CONTROVERSY
 Human cloning may produce subhumans to fight in our wars.
 Genetically modified food = not good
for you. Will it lead to health problems
in the future?
 Will it lead to designer babies?
 What if it leads to babies with
disorders?
 Lack of genetic variety
 Many more issues!!!!!!!
Does the
evidence
match
the
known
sample?
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