MEIOSIS provides for genetic
variation…how much variation
you might ask???
Consider an organism with
only 7 pairs of chromosomes
27 = 128 possible
combinations
which means 128 different sperm and 128
different eggs
If you fertilize any egg with
any sperm128 X 128 =
16,384 possible offspring
Now consider humans with 23
pairs of chromosomes…
23
2
means more than 8
million eggs or sperm
and
23
2
23
2
X
= 70 TRILLION
POSSIBILITIES!!!
YOU ARE UNIQUE!!!
Let‘s look more closely at how
you got that way
The Awesome
Power of the Gene
Understanding: The Power of Genes
The thing about Genetics is it uses lots of
funky words and if you don’t learn the
words the next few weeks in biology are
going to sound like you are living on
another planet with a bunch of
Klingons…and you will be dazed and
confused. As well as getting a very bad
grade. Soooooooo…….
Genetics Vocabulary
(flash cards perhaps???)
allele
crossing-over
diploid
gamete
genotype
haploid
homozygous
chromosome
cross-pollination
dominant
gene
heredity
heterozygous
hybrid
independent assortment
phenotype
recessive
self-pollination
meiosis
purebred
segregation
trait
SO STUDY
YOUR
VOCABULARY!
BECAUSE
THERE WILL BE
A QUIZ!!!
In the beginning
there was….
Hmm…what was there?
HEREDITY
GENETICS
GREGOR MENDEL
Parts of a Flower
Self-pollination
vs.
Cross- pollination
Incomplete Dominance
the phenotype of the
heterozygous is intermediate
between those of the two
homozygous
Co-dominance
causes the phenotype of both
homozygous to be expressed in
the heterozygous; both alleles
are expressed equally
ROAN
Multiple Alleles
many genes have more than
two alleles for a trait; more than
two possible alleles exist in a
population
POLYGENIC TRAITS
• Traits are usually quantified by
measurement rather than counting.
• Two or more gene pairs contribute to the
phenotype.
• Phenotypic expression of polygenic traits
varies over a wide range.
SEX LINKED
CHARACTERISTICS
GENETIC ENGINEERING
OR
BIOTECHNOLOGY
BREEDING STRATEGIES
SELECTIVE BREEDING• INBREEDING• HYBRIDIZATION-
Pedigrees
THE HUMAN PEDIGREE
CLONING
http://www.pbs.org/wgbh/nova/body/cloningprocess.html
In Vitro Fertilization
http://video.nationalgeographic.co
m/video/science/health-humanbody-sci/human-body/ivf-sci/
KARYOTYPING
DNA Clears Florida Man After
35 Years Behind Bars
BARTOW, Fla. — James Bain used a cell phone for the first time
Thursday, calling his elderly mother to tell her he had been freed
after 35 years behind bars for a crime he did not commit.
Mobile devices didn't exist in 1974, the year he was sentenced to
life in prison for kidnapping a 9-year-old boy and raping him in a
nearby field.
Neither did the sophisticated DNA testing that officials more
recently used to determine he could not have been the rapist.
"Nothing can replace the years Jamie has lost," said Seth Miller, a
lawyer for the Florida Innocence Project, which helped Bain win
freedom. "Today is a day of renewal."
Bain spent more time in prison than any of the 246 inmates
previously exonerated by DNA evidence nationwide, according to
the project. The longest-serving before him was James Lee
Woodard of Dallas, who was released last year after spending
more than 27 years in prison for a murder he did not commit.
DNA TESTING
•
•
•
•
Polymerase Chain Reaction
DNA Electrophoresis
Recombinant DNA
The Ethics of DNA
POLYMERASE CHAIN REACTION
or PCR
DNA ELECTROPHORESIS
http://www.youtube.com/watch?v=
vq759wKCCUQ
ETHICS is the study and
philosophy of human
conduct with an emphasis
on the determination of right
and wrong. Perceptions
within societies are used to
determine current
definitions.
What are some examples
of ethical issues?
BIOETHICS
BIOETHICS is, therefore, the
study and philosophy of
human conduct as it relates
to the advances in modern
biology and medicine , and
societies perception of their
value on the continuum.
Examples of bioethical issues
Sperm Donors Father up to 150 Children, Accidental Incest a Concern
The New York Times uncovered an astonishing example in a recent article, telling the story of a mother who did some
research and found that her son, conceived with artificial insemination, was one of 150 children who sprang from the
same source. The growing use of artificial insemination has made such networks of sperm donor half-siblings
increasingly common, if usually smaller than 150.
The result is more than just eery situations (the mother mentioned above vacations with the other families and
remarked on how the children look alike). For some parents, the prevalence of babies from a single donor has raised
the possibility that their children may inadvertently cross paths with half siblings and begin relationships.
"My daughter knows her donor's number for this very reason," the anonymous mother of a teenager conceived via
sperm donation told the Times. "She's been in school with numerous kids who were born through donors. She's had
crushes on boys who are donor children. It's become part of sex education."
Also of concern is the fact that there are minimal regulations on who can or cannot donate sperm. Unlike in some other
countries, the United States does not place a limit on how many children can come from a single donor. Donors only
have to be screened for sexually transmitted diseases and some hereditary diseases, and their ability to remain
anonymous makes it very difficult for their children to access information such as medical conditions they may inherit.
Major Ethical Principles
Do no harm
Do good
Do not violate individual freedom
Be fair
Tell the Truth
Keep your promise
Respect confidences
How much harm can justifiably be risked to
effect good?
Attempt to avoid undesirable exceptions
RECOMBINANT DNA
HUMAN GENOME
PROJECT
The Human Genome Project