Download Prentice Hall Biology - Mid

Go to
Section:
Interest Grabber
Section 13-1
A New Breed
The tomatoes in your salad and the dog in your backyard are a result of
selective breeding. Over thousands of years, humans have developed
breeds of animals and plants that have desirable characteristics. How do
breeders predict the results of crossing individuals with different traits?
Go to
Section:
Interest Grabber continued
Section 13-1
1. Think of two very different breeds of dogs that are familiar to you. On a
sheet of paper, construct a table that has the following three heads: the
name of each of the two dog breeds, and “Cross-Breed.
2. The rows of the table should be labeled with characteristics found in
both breeds of dogs. Examples might include size, color, type of coat,
intelligence, aggression, and so on.
3. Fill in the column for each of the two dog breeds. In the column labeled
“Cross-Breed,” write in the characteristic you would expect to see in a
cross between the two breeds you have selected.
Go to
Section:
Characteristic
Size
Color
Type of Coat
Go to
Section:
Dog 1
Dog 2
Cross Breed
(Hybrid)
Go to
Section:
Go to
Section:
Mutations
Normal Green-cheek Pair
Go to
Section:
Cinnamon Green-cheek pair,
Yellow-sided Green-cheek
Concept Map
Section 13-1
Selective
Breeding
consists of
Inbreeding
Hybridization
which crosses
which crosses
Similar
organisms
Dissimilar
organisms
Organism
breed A
Go to
Section:
for
example
for
example
Organism
breed B
Organism
breed A
which
which
Retains desired
characteristics
Combines desired
characteristics
Hybridization of two different plants leads to a
hybrid with a combination of both parents traits
Go to
Section:
Hybrids only
possible
between closely
related species
Offspring are
usually sterile
Go to
Section:
Mutations
Increases variation
which is the raw
material for selective
breeding and evolution
Sometimes mutation
can be introduced by
mutagens like X-rays
and chemicals.
Go to
Section:
Seedless Watermelons are triploid (3N)
It is POLYPLOID
Go to
Section:
Interest Grabber
Section 13-2
The Smallest Scissors in the World
Have you ever used your word processor’s Search function? You can
specify a sequence of letters, whether it is a sentence, a word, or
nonsense, and the program scrolls rapidly through your document,
finding every occurrence of that sequence. How might such a function
be helpful to a molecular biologist who needs to “search” DNA for the
right place to divide it into pieces?
Go to
Section:
Interest Grabber continued
Section 13-2
1. Copy the following series of DNA nucleotides onto a sheet of paper.
GTACTAGGTTAACTGTACTATCGTTAACGTAAGCTACGTTAACCTA
2. Look carefully at the series, and find this sequence of letters: GTTAAC.
It may appear more than once.
3. When you find it, divide the sequence in half with a mark of your pencil.
You will divide it between the T and the A. This produces short segments
of DNA. How many occurrences of the sequence GTTAAC can you find?
Go to
Section:
Go to
Section:
Restriction enzymes can only
fit the DNA at a specific base
sequence EX: CTTAAG
Animation
Animation
Go to
Section:
Go to
Section:
Go to
Section:
Go to
Section:
Plasmid
Go to
Section:
Recombinant DNA
Ligase seals
backbone
Go to
Section:
Only some bacteria get
a plamid
TRANSFORMED
Antibiotic added
to screen out
those without
plasmid
Genetic Marker
Only one
plasmid has the
FROG gene
Frog rRNA
labelled with
radioactive
tracer is used to
find which
plasmid has the
frog gene
Go to
Section:
Penicillin link
Bacteria with frog gene can
now be cloned
The plasmids are reinserted into the bacteria, but only
some take up the plasmid -they must be SCREENED OUT
DNA probe (with
radioactive tag)
complementary to frog
gene
Animation
Go to
Section:
Cloning Animation
Animation of removing introns to
put eu gene in prokaryote
Go to
Section:
Four Stages in Genetic Engineering
1.
2.
3.
4.
5.
Cleaving DNA
Producing Recombinant DNA
Transforming (and then Cloning Cells)
Screening Target Cells with gene
(Clone the screened Target cell)
Go to
Section:
2. Why does cell division
produce bacterial cells that
all contain the protein-V
gene?
When the bacterial cell
undergoes cell division, the
recombinant plasmid is
replicated.
Go to
Section:
P 365
Go to
Section:
Plasmid used as
a vector
Go to
Section:
Phage used as a vector
Go to
Section:
Go to
Section:
Ti plasmids in
bacteria can cause
tumors in plants
If the tumor causing gene is removed
from the plasmid and a useful gene
spliced in - the Ti plasmid can be used as
a VECTOR to move genes into plants
Go to
Section:
Go to
Section:
Go to
Section:
Go to
Section:
1. How is the Agrobacterium cell used in this process?
The Agrobacterium cell is the source of the plasmid into which a
new gene is inserted. The recombinant plasmid is then introduced
into plant cells.
Go to
Section:
2. What is the goal of this process?
The goal is to produce plants with desired traits.
Go to
Section:
Bt Toxin genetically modifies corn
Advantage
•Kills pests
•No pesticides sprayed
•Costs less for insecticide
Disadvantage
•May kill other insects EX
pollen may kill passing
butterflies and bees
•Corn seeds cost more
Go to
Section:
Knockout Genes
Section 13-3
Recombinant DNA
Flanking sequences
match host
Host Cell DNA
Target gene
Recombinant DNA replaces
target gene
Modified Host Cell DNA
Go to
Section:
Target genes may be inserted
into the Host cells DNA if the
flanking sequences are the
same – theses are called knock
out genes.
Geneticists had taken
the luciferase gene
from a firefly and
inserted it into a
tobacco plant. This
meant that when the
plant was fed with
luciferin the result was
a plant that glows in
the dark!
Go to
Section:
Go to
Section:
Plucky is an albino Xenopus laevis The
frog expressing green fluorescent
protein (GFP) in her eye. GFP is a was
jellyfish protein that fluoresces
bright green when illuminated by
blue light. GFP is used as a
genetic marker to show the
appearance of a
TRANSGENIC ORGANISM
Go to
Section:
first cloned mouse
created at UH
Go to
Section:
•GFP Amino Acids were sequenced
•Then Bases for DNA were
sequenced
•GFP used as GENETIC MARKER
to show that another gene has been
inserted
Go to
Section:
• Plant Genome Video
Go to
Section:
Figure 13-13 Cloning of the First Mammal
Section 13-4
A donor cell is taken from
a sheep’s 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.
Embryo
Cloned Lamb
The embryo
develops normally
into a lamb—Dolly
Go to
Section:
The fused cell
begins dividing
normally.
Foster
Mother
The embryo is placed
in the uterus of a foster
mother.
Go to
Section:
Mimi
THE FIRST MOUSE CLONES
The clones (two brown mice at bottom) are genetic duplicates of the mouse at top
right, which donated its cumulous cells. They are the result of a technique perfected at
the University of Hawaii in 1998
Go to
Section:
WILBUR WANNABES
The first litter of cloned pigs, born in 2000 in Virginia, demonstrate that cloning could be
used to generate organs for human transplant in the near future
Go to
Section:
Not to be outdone, Chinese researchers are perfecting cloning techniques in the
hope of using the procedure to preserve the country's beloved panda species. For
practice, they began with more common species, including goats like Yangyang
(above). Cloning remains a tricky process; only 2%-5% of the eggs that start out
as clones develop into live animals. The good news is that once they survive past
the first year, clones like Yangyang, celebrating her sixth birthday, are relatively
healthy.
Go to
Section:
Dr. Severino Antinori, an Italian embryologist,
fires up the press in 2001 after announcing
plans to clone the first human to help infertile
couples have children. He claimed one of his
patients was carrying a clone, but he failed to
confirm his tale or produce the child. His
comments launched a debate over the ethics
of cloning human beings; countries like
Britain and South Korea have since made it
illegal to clone people, while the U.S.
Congress has yet to ban the process.
Go to
Section:
Animation
Link to PCR Animation on Web
Go to
Section:
Figure 13-8 PCR
Section 13-2
DNA polymerase adds
complementary strand
DNA heated to
separate strands
DNA fragment
to be copied
Go to
Section:
PCR
cycles 1
2
3
4
5 etc.
DNA
copies 1
2
4
8
16 etc.
Restriction Enzymes
Section 13-2
Recognition sequences
DNA sequence
Go to
Section:
Restriction Enzymes
Section 13-2
Recognition sequences
DNA sequence
Restriction enzyme
EcoRI cuts the DNA
into fragments.
Go to
Section:
Sticky end
Figure 13-6 Gel Electrophoresis
Section 13-2
Power
source
DNA plus restriction
enzyme
Longer
fragments
Shorter
fragments
Mixture of DNA
fragments
Gel
http://learn.genetics.utah.edu/units/biotech/gel/
Gel Electrophoresis simulation
Go to
Section:
Go to
Section:
P 373
Differences in DNA sequences on homologous
chromosomes result in different restriction fragment
length patterns RFLP
- these may be sorted by length using gel
electrophoresis
Go to
Section:
Go to
Section:
Different people have
different DNA
-DNA when cut by
enzymes will leave
different size fragments
-which will separate into
different electrophoresis
patterns
-a DNA fingerprint
If there is only a small
sample of DNA
available- more copies
can be made by PCR polymerase chain
reaction (p371)
Link to DNA
Fingerprint Lab
Go to
Section:
Single stranded cDNA is
made from a target cell’s
active mRNA and tagged
with a fluorescent dye
DNA Microarray
Identifies Active Genes
A DNA Chip is a
microarray of many spots
where single stranded
DNA is attached – each
strand representing a
different gene.
If a gene is active the dye labeled cDNA will attach and
cause that spot to light up when a laser strikes it. This tells
you which genes are active.
Go to
Section:
Figure 13-7 DNA Sequencing
Section 13-2
Go to
Section:
Interest Grabber
Section 13-3
Sneaking In
You probably have heard of computer viruses. Once inside a
computer, these programs follow their original instructions and
override instructions already in the host computer. Scientists use
small “packages” of DNA to sneak a new gene into a cell, much as a
computer virus sneaks into a computer.
Go to
Section:
Interest Grabber continued
Section 13-3
1. Computer viruses enter a computer attached to some other file.
What are some ways that a file can be added to a computer’s
memory?
2. Why would a person download a virus program?
3. If scientists want to get some DNA into a cell, such as a bacterial
cell, to what sort of molecule might they attach the DNA?
Go to
Section:
Interest Grabber
Section 13-4
The Good With the Bad
The manipulation of DNA allows scientists to do some interesting
things. Scientists have developed many transgenic organisms, which
are organisms that contain genes from other organisms. Recently,
scientists have removed a gene for green fluorescent protein from a
jellyfish and tried to insert it into a monkey.
Go to
Section:
Interest Grabber continued
Section 13-4
1. Transgenic animals are often used in research. What might be the
benefit to medical research of a mouse whose immune system is
genetically altered to mimic some aspect of the human immune
system?
2. Transgenic plants and animals may have increased value as food
sources. What might happen to native species if transgenic
animals or plants were released into the wild?
Go to
Section:
Flowchart
Section 13-4
Cloning
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.
Go to
Section:
Figure 13-13 Cloning of the First Mammal
Section 13-4
A donor cell is taken from
a sheep’s 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.
Embryo
Cloned Lamb
The embryo
develops normally
into a lamb—Dolly
Go to
Section:
The fused cell
begins dividing
normally.
Foster
Mother
The embryo is placed
in the uterus of a foster
mother.
Link to Cloning Mimi
Go to
Section:
Go to
Section:
ADA: The First Gene Therapy Trial
• A four-year old girl became the first gene therapy
patient on September 14, 1990 at the NIH Clinical
Center. She has adenosine deaminase (ADA)
deficiency, a genetic disease which leaves her
defenseless against infections. White blood cells
were taken from her, and the normal genes for
making adenosine deaminase were inserted into
them. The corrected cells were reinjected into her.
Dr. W. French Anderson helped develop this
landmark clinical trial when he worked at the National
Heart, Lung, and Blood Institute
Go to
Section:
Video
Gene Transfer
Click the image to play the video segment.
Go Online
Links from the authors on genetically modified foods
Interactive test
For links on recombinant DNA, go to www.SciLinks.org and enter the
Web Code as follows: cbn-4132.
For links on genetic engineering, go to www.SciLinks.org and enter the
Web Code as follows: cbn-4134.
Interest Grabber Answers
1. Think of two very different breeds of dogs that are familiar to you. On a
sheet of paper, construct a table that has the following three heads: the
name of each of the two dog breeds, and “Cross-Breed.
Encourage students to refer only to breeds with which they are familiar.
2. The rows of the table should be labeled with characteristics found in both
breeds of dogs. Examples might include size, color, type of coat,
intelligence, aggression, and so on.
Additional traits might include shape of ears, shape of muzzle (pointed or
square), or length of legs with respect to body.
3. Fill in the column for each of the two dog breeds. In the column labeled
“Cross-Breed,” write in the characteristic you would expect to see in a
cross between the two breeds you have selected.
Students will likely assume that traits of the cross-breed are intermediate
between those of the two parent breeds.
Interest Grabber Answers
1. Copy the following series of DNA nucleotides onto a sheet of paper.
GTACTAGGTTAACTGTACTATCGTTAACGTAAGCTACGTTAACCTA
2. Look carefully at the series, and find this sequence of letters: GTTAAC. It
may appear more than once.
1–2: Remind students to check their copies for accuracy before they begin
the next step.
3. When you find it, divide the sequence in half with a mark of your pencil.
You will divide it between the T and the A. This produces short segments of
DNA. How many occurrences of the sequence GTTAAC can you find?
Students should find three occurrences of the sequence:
GTACTAGGTTAACTGTACTATCGTTAACGTAAGCTACGTTAACCTA
Interest Grabber Answers
1. Computer viruses enter a computer attached to some other file. What are
some ways that a file can be added to a computer’s memory?
A file can be downloaded from a diskette, a CD, or the Internet.
2. Why would a person download a virus program?
The computer user would not willingly download a virus but would
download a program that was useful.
3. If scientists want to get some DNA into a cell, such as a bacterial cell, to
what sort of molecule might they attach the DNA?
Possible answers: a useful protein or a strand of DNA that the cell would
recognize and accept
Interest Grabber Answers
1. Transgenic animals are often used in research. What might be the benefit
to medical research of a mouse whose immune system is genetically
altered to mimic some aspect of the human immune system?
Students may say that a mouse with a humanlike immune system would be
a good laboratory model for immune research.
2. Transgenic plants and animals may have increased value as food sources.
What might happen to native species if transgenic animals or plants were
released into the wild?
Transgenic organisms might disrupt normal balances in ecosystems and
could breed with natural populations, changing them.
This slide is intentionally blank.