The Science of Steroids

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Transcript The Science of Steroids

1/31/13 PERIOD 4
1.
2.
3.
4.
Attendance
Mitosis Brainpop
Time to finish work from
yesterday.
Time to finish textbook
work from Monday
STEPS TO MAKING A CHEWING GUM NEURON:
1.
2.
3.
Chew your gum.
Fold a piece of wax paper so it looks like a book.
On the inside of the book – use your chewed
gum to make a neuron.
a.
b.
c.
d.
e.
f.
g.
Stretch it out to make axon (globs on both ends)
Make cell body from the bigger glob
Make dendrites from the cell body
Make terminal branches from the smaller blob. The
very tips of these will be the axon terminals.
Put the pea in the middle of the cell body to be the
nucleus.
Put rice spaced out on the axon to be the myelin
sheaths.
The spaces in between the rice will be the Nodes of
Ranvier.
4. Fold over the wax paper to close the book. Press
down lightly.
 5. Cut the wax paper around your neuron.
 6. Cut out an interesting pattern of green papers to act
as a frame to go under your wax paper.
 7. Glue all to a regular piece of copy paper.
 8. Use the little sticky dots to label the eight parts.
 9. Make a key of the dot numbers and names. Include
the function of each part too.
 10. Look over the grading rubric to make sure
that you will get maximum credit for this lab!
Staple everything together – including rubric and
turn it in!
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
You will need: gum, paper clip, wax paper, five grains of
rice, one pea, sticky label dots, glue
WHAT PARTS DO YOU KNOW THAT
ARE IN THE NERVOUS SYSTEM?
 Brain
• Spinal Cord
• Peripheral Nerves
http://outreach.mcb.harvard.edu/materia
ls.htm
http://outreach.mcb.harvard.edu/materia
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WHAT MAKES UP THE BRAIN, THE SPINAL
CORD OR YOUR PERIPHERAL NERVES?
 Neurons
are “the
cell”
 Cell body
 Nucleus
 Axon
 Dendrite
 What do you think
surrounds the cell?
 What other
organelles would be
needed?
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
http://outreach.mcb.harvard.edu/materia
ls.htm
http://outreach.mcb.harvard.edu/materia
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HOW ARE NEURONS CONNECTED?

Synapses!!
WHY ARE NEURONS CONNECTED?
MORE NEURON
CONNECTIONS!
Close up look at your
synapse
AXON
What is this
in the
membrane?
The synapse where the action
happens
The next cell’s plasma
membrane
Transport
protein
HOW DOES THE SYNAPSE CARRY THE
SIGNAL?
1.Electrical current travels down the axon
2.Vesicles with chemicals move toward the membrane what is that called?
3.Chemicals are released and diffuse toward the next
cell’s plasma membrane
4.The chemicals open up the transport proteins and
allow the signal to pass to the next cell - what type of
diffusion is this?
http://outreach.mcb.harvard.edu/materia
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The synapse carries a signal from cell
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to cell
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1
2
3
4
THERE ARE LOTS OF PROTEINS AND
CHEMICALS IN YOUR BODY TO DO THE WORK
Why is it important that it is an electrical
current?
http://outreach.mcb.harvard.edu/materia
ls.htm
http://outreach.mcb.harvard.edu/materia
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ARE ALL NEURONS EQUAL IN SIZE?
 Brain
vs spinal cord vs peripheral nerves?
About how many neurons are in the human brain?
100 billion
About how many neurons are in the spinal cord?
1 billion
How long do you think the longest axon in the world is?
around 15 feet
How many synapses
are in one neuron?
1,000 to 10,000!!
http://outreach.mcb.harvard.edu/materia
ls.htm
THIS SCIENCE IS CALLED
N
EUROBIOLOGY
 Looking at the actual cells - how do they work?





Looking at the connections - how and when do they work?
Looking at what can change normal cells and connections
Looking at diseases that occur in the brain
One of the largest areas still unknown
The you that is you is because of your neurons connecting!
http://outreach.mcb.harvard.edu/materia
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http://outreach.mcb.harvard.edu/materia
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WHAT DO YOU THINK CAN CHANGE
NEURONS AND THEIR CONNECTIONS?
 Accidents
 Drugs
 Alcohol
 Disease
http://outreach.mcb.harvard.edu/materia
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ACCIDENTS

Physical injury of your neurons
Drugs and alcohol bind important receptors on
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neurons
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Repeated binding causes the neuron to
die
http://outreach.mcb.harvard.edu/materials.htm
http://outreach.mcb.harvard.edu/materia
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DRUGS = NEURON DEATH
http://outreach.mcb.harvard.edu/materia
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ALCOHOL DAMAGES DENDRITES - CAN REPAIR
AFTER ABSTINENCE
http://outreach.mcb.harvard.edu/materia
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Alcohol blocks
receptors and
slows down
transmission
•Parkinson's Disease
•ALS - Lou Gehrig’s Disease
•Huntington’s Disease
•Multiple Sclerosis
•Alzheimer's
•Cerebral Palsy
•Epilepsy
•? SIDS
http://outreach.mcb.harvard.edu/materia
ls.htm
100 Billion or so neurons - what’s the
problem with some of them dying?
•Does everyone react the
same way to accidents, or
drugs and alcohol?
•Do all organisms react the
same to all stimulus?
•Cells multiply all the time
- will your neurons?
•Which of your activities
use your neurons?
http://outreach.mcb.harvard.edu/materia
ls.htm
What if
neurons
die here?
or
here
or
here
http://outreach.mcb.harvard.edu/materia
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or
here
or
here
Thinking About…
…Doping for Gold
a video about the beginning of organized doping in
international athletic competition
Let’s Divide Our Thinking Into:
 The Science of Steroids
 The Influence of a Society on Steroid Use
 In the GDR in the 1960s – 1980s
 In international competition today
So…Is Steroid Use Good or Bad?
 Let’s take a look at what steroids can
actually do!
The Science of Steroids
Question:
What effects can
testosterone - based
steroids have on the
human body?
She’s a lovely lass. But are you a little afraid to bring her home to meet Mom?
Concepts of
beauty are
often cultural.
Body builders
have their
own culture.
What are
your views of
symmetry
and strength
in the human
body?
Most Steroid Users Don’t Look as Extreme
as the Previous Two Photos!
Max Jaben, an American on
the Israeli Olympic Swim Team
in 2008 is shown here. He
tested positive for the anabolic
steroid called boldenone in
July 2008.
He was banned from the
August 2008 Olympics in July
2008. The ban was for 2 years.
columbiamissourian.com
Numerous countries had top
athletes banned from the
2008 Games because they
tested positive for steroids.
The Science of Steroids
How do steroids
produce these changes?
Well…the story starts with the
membrane of the nucleus that guards
against uninvited visitors to that precious
prisoner of the nucleus, the DNA.
Except for…
…the fact that steroids have a “special
pass.” Once a steroid gets into the cell, it
picks up its pass, and gets carried right
into the nucleus!
The special pass is called the
hormone receptor. The
receptionist says “The doctor will see
you now!” So what does the hormone
receptor “say”?
“The nucleus will see you now!”
And what language is the steroid and
the hormone receptor speaking? Of
course, it’s the language of the body…
Shape!
Let’s visualize this – is your pen
ready to jot some info on this
shape conversation?
Outside of cell
Steroid
Inside of cell
1
Cell membrane
2
Nuclear membrane
4
Steroid
receptor
5
6
3
New protein
synthesized
How do anabolic steroids work? Let’s break it down in order
1
____________is outside the_______.
2
Steroid ________across ______________
3
Steroid binds to the “pass,” the ____________
___________. Together they are the hormone
receptor complex (HRC). The ______ enters
the__________________.
4
_____binds with_____. This
activates a section of DNA.
5
DNA _________________ for
making a _____________are
carried out of the____________.
6
__________molecules are
made and _____________
increases.
The Science of Steroids
What Effects Do Steroids Have?
 They increase protein synthesis in cells, so cells make
more tissue
 This process of cell tissue building is called anabolism;
the drugs are often called anabolic steroids
 Muscle tissue breaks down more slowly
 Cells differentiate more easily into muscle cells instead
of fat cells
Additional Positive Effects of Anabolic
Steroids
These can be used for good medical
purposes:
 Increase muscle tissue healing
 Increase appetite
 Increase bone growth
 Stimulate delayed puberty
But Negative Side Effects Can Occur
 Influence masculine traits such as hair growth, vocal
cord development in women
 Influence hair loss and low sperm count in men
 Can have negative effects on liver tissue, reproductive
tissue and heart muscle
 Increase competitiveness and aggressiveness because
anabolic steroids affect the limbic system of the brain
The Science of Steroids
Let’s Recap: The Science of Steroids
What special ability do anabolic steroids have in the cell?
They pick up a “pass” to enter the nucleus.
What is the term for the “pass?”
Hormone receptor
Once in the nucleus, then what?
The HRC activates a section of DNA to give directions
What directions from the DNA does the steroid activate?
Make more tissue!
Where is this tissue actually made?
At the organelles called ribosomes in the cell cytoplasm.
The Science of Steroids
What is an anabolic steroid?
 A type of steroid that produces tissue growth
 Are all steroids anabolic?
No. Some steroids reduce swelling and don’t cause tissue
growth. This type is called a cortico-steroid. They are not
likely to be abused because they don’t cause tissue building.
Switch Gears Now!
 What is the effect of a society on steroid use?
The Influence of a Society on Steroid Use
The Geography of the GDR
http://www.memorial-caen.fr/10event/gb/ciel_tex21.htm
The GDR (German
Democratic Republic),
known as East
Germany was smaller
than the FRG (Federal
Republic of Germany),
or West Germany.
What countries border
the GDR?
Those countries
were under the
control of the Soviet
Union
The Influence of a Society on Steroid Use
W
H
Y
?
france24.com
all-athletics.com
Heidi Kreiger
Andreas Kreiger
Heidi Kreiger
The Influence of a Society on Steroid Use
http://kristinbjorg.blogcentral.is/
beijing-olympics2k8.blogspot.com
http://transgriot.blogspot.com/2008/07/how-blue-pills-turned-heidikrieger.html
Happier Times Now
The human spirit, like the human body, has
tremendous abilities to heal after traumatic stress.
The Influence of a Society on Steroid Use
 The GDR wanted to use successful
sports programs to cheer up a
depressed nation.
 What happened to the chosen
children and young adults?
 How did the athletes get the steroids?
 Did they know they were receiving
steroids?
 How did steroids affect their training
At first?
Later?
The Influence of a Society on Steroid Use
 If you were one of the athletes, how
do you think you would have reacted
to your suspicions that you were
getting more than vitamins?
What would have been the
pressures on you in your decisions?
 What would have happened to you?
How would you feel about your
medals?
Decades later: the former chief doctor of East
Germany's swimming team was convicted of giving
performance-enhancing drugs to young athletes
without telling them.
 Lothar Kipke, 72,
was fined 7,500
German marks
($3,900) and given a
15-month suspended
jail sentence.
news.bbc.co.uk
 He was convicted on
more than 50 charges
of causing bodily harm
by giving them
steroids.
The Influence of a Society on Steroid Use
1. Judge Peter Faust said
Kipke had played a key role
in the East German system
to give swimmers steroids
in order to boost their
performance, and that he
knew the drugs “harmful
side effects.”
2. The doctor admitted that
he had provided the drugs - a
widespread practice in
communist East German
sport - but he said that in the
1970s little was known about
their potential side-effects.
3. Prosecutors said that neither the
swimmers nor their parents were told about
the drugs and were therefore unaware that
they might suffer side-effects.
4. The women involved in the case are
now suffering from such problems as
disturbed muscle growth, excessive body
hair and a deepened voice.
Two former East German
swimming champions blame
their babies' disabilities on the
steroids.
One has a daughter who was
born blind, the other a son with
a club foot.
They say Dr Kipke continued to
give them drugs despite
knowing the potential
consequences
(Lothar Kipke, 72, was fined 7,500 German marks ($3,900) and
given a 15-month suspended jail sentence.)
The Influence of a Society on Steroid Use
Our Hero:Tessa Sanderson of England
 Won the Gold, finally, in 1984!
 Steadfastly refused to use steroids throughout her career.
 Prevailed over East German Ruth Fuchs,
her long-time steroid-using nemesis who
had beaten her many times.
Photo: GETTY IMAGES
Bournelocal.co.uk.com. 08/11/11
What were the influences on Tessa
Sanderson to NOT take steroids?
 She competed internationally at a time when
steroids were being taken by her competitors
 This included GDR athlete Ruth Fuchs who
beat her many times! (Ruth Fuchs was given
steroids and by the 1970s steroid use was
suspected of the East Germans by other
countries)
 Why do you think she resisted taking
steroids?
 How do you think you would have responded
if you were in her shoes?
Science doesn’t have its own
independent values of good or
bad, right or wrong, righteousness
or evilness.
These are values placed on the
use of science by a society
through its laws, or by individuals
in the society, sometimes in
opposition to current laws.
In the GDR, the government thought that people
didn’t need to know about steroids, they just
needed to perform.
In our society, anabolic steroid use by athletes is
illegal. Why? Is this fair or unfair?
Should athletes be legally allowed to take risks
with their health?
If everyone KNEW who was taking steroids would
that affect competition?
Would it make athletes less likely to abuse steroids
or more likely?
What do you think?
Should steroid use by athletes be illegal or legal?
The Endocrine system
Glands and hormones
 Hormones- chemical
messengers carried by blood May stimulate other glands
 Regulate growth, development,
metabolism, sex processes
 Hormones need a
specific receptor
on a specific cell to
do their job
 Major Glands of the Endocrine system
 Pituitary
 Thyroid
 Parathyroid
 Adrenal.
 Pancreas
 Ovaries
 Testes
Pituitary gland
 Master gland of body
 Located in the depression of sphenoid bone
 Produces many hormones that affect other glands
 thyroid stimulating hormone
 Somatotropin- growth hormone
 Lutenizing (LH)- causes ovulation
 ICSH- causes testes to secrete testosterone
 Melanocyte stimulating- distribution of melanin in skin
 ADH- antidiuretic hormone
 Giantism- oversecretion of
somatotropin before
puberty
 Dwarfism- undersecretion
of somatotropin. Cause:
tumor, injury, infection,
genetics
 Diabetes insipidus-
decreased ADH
 Thyroid- produces
hormones that control
metabolism and calcium in
blood.
 Thyroid gland must have
any source of iodine



goiter- not enough iodine
hyperthyroidism
hypothyroidism
 Adrenal glands
 Located just above the




kidney
Secretes many hormones
Epinephrine
Norepinephrine
Many steroid hormones,
inc estrogen and androgens.
 Pancreas pancreatic juices into the
intestine
 secretes insulin, a hormone
that transports glucose into
cells.
 Also secretes glucagonincreases glucose in
bloodstream
 Diabetes Mellitus Cause- decreased secretion of insulin
 Symptoms
 Excessive thirst, excessive urination, hyperglycemia, slow healing of
skin infections
 Affects 21 million in US: 7% of population
 Estimated 1/3 of people who have diabetes don’t know it
 225,000 die each year
 132 billion/year- 10% of our health care spending
 Insulin was the first hormone identified (late 1920's)
which won the doctor and medical student who discovered it
the Nobel Prize (Banting and Best)
 1982 - Human Insulin - First ever approved genetically
engineered human therapeutic by Genentech
The Human Reproductive System
Male Reproductive System
urinary bladder
seminal vesicles
prostate gland
urethra
penis
rectum
epididymis
Cowper’s gland
testis/testes
scrotum
vas deferens
Male Reproductive System
(frontal view)
See p. 62 in Review book
Male Reproductive System
1.
2.
Scrotum – sac of skin that holds testes. Hangs below
body to keep testes cool. Sperm cannot be produced
if body is too warm. Testes move into scrotum just
before birth.
Testis/testes – male gonads. Made up of small, coiled
tubes – seminiferous tubules. 300-600 per testis.
Immature sperm made here.
Secrete testosterone
Male Reproductive System
3.
4.
5.
Epididymis – storage area in upper rear of testis.
Immature sperm move here to mature – takes 18
hours.
Vas deferens – tube that leads upwards from each
testis into lower part of abdomen from epididymis.
Cowper’s gland – produces fluids that nourish sperm
and protect them from the acidity of female.
Combination of sperm and fluids - semen
Male Reproductive System
6. Rectum – holds wastes
7. Seminal vesicles – same job as Cowper’s gland
8. Urinary bladder – stores urine
9. Prostate gland – same job as Cowper’s gland and seminal
vesicles
10. Urethra – passageway for excretion of urine and for sperm
to leave body. Vas deferens empties into urethra
Male Reproductive System
11. Penis – male reproductive organ. Facilitates internal
fertilization
Ejaculation – muscular contractions force semen through
urethra. Before, during and after ejaculation reflex actions
keep outlet of bladder closed
Hormones and Negative Feedback in
Males
 Negative Feedback – change that leads to a response that
causes something to counteract that change
 Luteinizing Hormone (LH) – stimulates testes to produce
testosterone
 Testosterone – stimulates development of sperm. Once
there is a large number of sperm, puberty is complete.
Hormone Negative Feedback System
What is the effect of high levels of LH?


Testosterone is produced
What is the effect of high levels of testosterone?


Slows production of LH which in turn slows production of
testosterone
What is the overall outcome of this on-off negative
feedback system involving LH and testosterone?


Nearly constant level of both hormones - homeostasis
Another Way of Looking at Negative
Feedback in the Male Reproductive System
Brain
Pituitary gland
Male Reproductive Organs
target cells – receptor cells
LH stimulates the testes cells
Male Reproductive System and
Hormones
1.
2.
3.
Explain how LH stimulates the testes to produce testosterone.
Circulates in the blood- reaches the testes target cells –
stimulates them to produce testosterone
What happens when the levels of testosterone are too high in
the body?
LH level drops
What is negative feedback and how does it maintain
homeostasis?
Change in conditions triggers response in body to
counteract that condition. Keeps hormones in balance
Female Reproductive System
oviduct
ovary
Urinary bladder
uterus
urethra
vagina
cervix
rectum
Female Reproductive System
(frontal view)
See p. 61 in Review book
Female Reproductive System
1.
Ovary – female gonads. Secrete estrogen – produces
secondary characteristics, menstrual cycle
Produces eggs – 2 ovaries 4cms long, 2 cms wide
Follicles – each ovary contains 200,000 egg sacs called
follicles. In each follicle is an immature egg.
All the eggs are present at birth. During the woman’s
lifetime 500 eggs mature
When an egg matures, follicle moves to surface of ovary.
Follicle breaks & releases the egg – ovulation
Egg can be fertilized for about 24 hours after ovulation
Female Reproductive System
2. Oviduct (fallopian tube) – Each ovary is near but not
connected to oviduct. Tube with funnel-like opening.
Cilia line it to create a current that draws the egg into the
tube. Egg is fertilized in the oviduct
3. Uterus – thick, muscular, pear-shaped organ. Once egg is
fertilized it finishes its development in uterus attached to
uterine wall
Female Reproductive System
4. Urinary bladder – storage of urine
5. Urethra – passage of urine to outside of body
6. Vagina (birth canal) – leads to outside of body
7. Cervix – narrow neck of uterus
8. Rectum – passage for wastes
The Menstrual Cycle
What is the menstrual cycle?
Cycle during which an egg develops and is released from
the ovary and the uterus is prepared to receive a
fertilized egg
Menarche: first menstrual period – usually occurs between 11
and 12
Menopause: time when a woman stops menstruating, usually
between 45 & 55 and is no longer able to conceive.
The Menstrual Cycle
The Menstrual Cycle
1. Menstruation: Loss of egg and uterine tissue via vagina if
fertilization does not occur
2. Follicle Stage (follicular stage): lasts 10 days, FSH & LH
levels increase, egg matures, follicle secretes estrogen to
prepare uterus
The Menstrual Cycle
3. Ovulation: High level of estrogen detected by
hypothalamus, increased LH, decreased FSH, follicle
bursts – egg released
4. Corpus Luteum Stage (Luteal Phase): LH converts
follicle to corpus luteum – secretes estrogen &
progesterone. Progesterone prepares uterus. Increased
progesterone keeps LH & FSH low
Another Way of Looking at Negative Feedback in
the Female Reproductive System (Hormones of
the Menstrual Cycle)
Brain
Pituitary gland
FSH (causes egg to mature in follicle)
LH (causes to egg to be let go = ovulation)
ovary
uterus
Estrogen (causes uterine lining to thicken
& build up to prepare for egg)
Progesterone (helps maintain uterine lining)
Hormones of Menstrual Cycle
What happens if fertilization occurs?
Corpus luteum keeps producing progesterone to maintain pregnancy.
After 5 weeks the embryo produces progesterone – this inhibits LH &
FSH so no menstrual cycle
What happens if fertilization does not occur?
There is no implantation – the corpus luteum breaks down.
Progesterone level drops, uterine lining breaks down – menstruation.
FSH & LH are produced again – new cycle
Average Menstrual Cycle is 28 days long
Ovulation to Implantation
oviduct
uterus
cervix
vagina
egg from
ruptured follicle
ovary
sperm
follicle
Ovulation to Implantation
1.
2.
3.
Ovary – produces estrogen & progesterone – meiosis
occurs & egg develops
Egg matures in follicle of ovary
Ovulation – egg released from follicle – may live for 24
hours
- egg moves into fallopian tube by cilia
Ovulation to Implantation
4.
Events in fallopian tube
a.
b.
Fertilization occurs here. Sperm lives 4-5 days (egg lives 1
day)
Zygote undergoes mitosis & travels down fallopian tube
within 6-10 days. Zygote is ready to implant into uterus.
Ovulation to Implantation
5.
Events in uterus
a.
b.
Implantation – embryo implants/embeds into uterine lining
& secretes hormone HCG to signal its arrival
Cell Differentiation – cells divide by mitosis & become
different due to gene expression. Different embryo parts
will form.
 Menstrual Cycle Animation