Transcript Aim: How does the endocrine system control activities of the body?

Aim: How does the endocrine system
control activities of the body?
1. Endocrine System
• Consists of a series of glands that secrete HORMONES into the
bloodstream (chemical regulation).
• The endocrine and
nervous system act
together to regulate
the functions of the
body (homeostasis).
• Allow for cell to cell communication.
2. Cell Membrane Proteins
Membrane Proteins:
1. Structural Proteins:
2. Transport Proteins:
(Channels)
3. Receptor Proteins
4. Enzymes
RECEPTOR
PROTEIN
STRUCTURAL PROTEIN
CHANNEL
3. Receptor proteins
RECEPTORS
Receptors found on the cell surface
aid in cell to cell communication.
Messengers (hormones) from other
cells bind to these receptors (based
on shape) and transfer information.
4. Hormones
• Are chemical messengers secreted into the blood
stream.
• Like a radio broadcast, HORMONES require a receiver
to get their message across.
• Cells must bear a RECEPTOR for the hormone being
broadcast in order to respond to them.
5. Nervous vs. Endocrine
• Nervous System
• Endocrine System
• Neurotransmitters
• Hormones
• Regulation
• Regulation
• Cell-Cell Communication
• Cell-Cell Communication
• FAST
• SLOW
Hypersecretion – Over secretion
Hyposecretion - Under secretion
6. Feedback
• Feedback Mechanism – involves a cycle in which the
output of a system “feeds back” to either modify or
reinforce the action taken by the system (ex. Negative
or Positive).
7. Negative Feedback:
A change in conditions triggers responses in your body
that counteract (negate) that change.
Example of Negative feedback
Thermostat senses temperature
change and switches off heating
system
Room temperature
increases
Room temperature decreases
Thermostat senses temperature
change and switches on heating
system
Negative Feedback:
Pituitary
Gland
TSH
Stimulates
Thyroid Gland
The product (thyroxine)
“Turns Off” the Pituitary Gland
(-)
Negative Feedback
Increased
Thyroxine
Level
9. Positive Feedback
Positive Feedback:
A change prompts a response, which leads to a
greater change and greater response.
Uterine
Contractions
Increase in pressure of
baby’s head against base
of uterus
Baby’s head hits
Base of uterus
Stronger
Contractions
The Guard Cells maintain
WATER
_______ in homeostasis.
Dry Sunny day
Humid day
Endocrine Glands
•Hypothalamus
•Pituitary Gland
•Thyroid Gland
•Adrenal Gland
•Pancreas
•Gonads
11. Hypothalamus
• Location: In the center
of the brain, it connects
the brain to the pituitary
gland.
• Function: Controls the
release of hormones
from the pituitary gland.
12. Pituitary Gland
• Location: base of the brain.
• Function: called the “MASTER GLAND”
Secretes:
(GSH) Growth Stimulating Hormone
• Hypersecretion: Giantism
• Hyposecretion: Dwarfism
a. Gigantism
• Over secretion of GROWTH HORMONE
b. Dwarfism
• Hyposecretion of GROWTH HORMONE
13. Thyroid Gland
• Location: Neck, in front of your trachea.
• Function: regulates metabolism
(WEIGHT) depending on iodine
intake.
• Hyposecretion:
• Weight Gain
• Goiter (due to an iodine deficiency)
a. Goiter
• A goiter is an ENLARGEMENT of the thyroid that results from a lack of
IODINE.
• TREATMENT:
Medication
Iodized Salt
14. Adrenal Gland
• Location: Top of the kidneys
• Function: Secretes:
Adrenaline – “Fight or Flight” response
15. Islets of Langerhans (Pancreas)
• Location: Pancreas
• Function: Secretes:
Together they regulate the amount of
Insulin – increases the amount of glucose taken up by body cells from
glucose
in the
blood
(homeostasis)
the blood
(decreases
glucose
in the
blood).
Glucagon – stimulates release of glucose from body cells into the blood
(increases glucose in the blood).
a. What are the effects of Insulin &
Glucagon?
What is glycogen?
Polysaccharide
b. Diabetes
Mellitus
• Pancreas cannot make enough insulin
• What happens to the blood glucose level if you have
no insulin?
• It remains high, & cells can’t use it for energy.
• If you were a doctor, how would you test someone for
diabetes?
• High glucose levels in blood and urine.
Vision Loss due to diabetes
16. Gonads
• Location: testes and ovaries
• Function:
Ovaries: (secrete)
estrogen – female sex characteristics
Testes: (secrete)
testosterone – male sex characteristics
17. Homeostasis/Dynamic Equilibrium
There are constant small corrections that normally keep
the internal environment within the limits needed for
survival.
How are humans adapted for
reproduction?
1. Human Reproduction
In order to aid our reproductive
processes, the human body has
two major anatomical
adaptations:
1. Reproductive System
2. Hormones
2. Female Reproductive System
• Ovaries – produce egg cells &
hormones estrogen & progesterone
• Oviduct or Fallopian Tube – site of
fertilization, carries egg to uterus
• Uterus – site where embryo develops
• Vagina – birth canal & site that allows
for internal fertilization
3. Male Reproductive system
• Testes – produce sperm & hormone
testosterone
• Scrotum – sac that keeps testes cool
• Vas deferens - carry sperm from testes
to penis
• Seminal vesicle & Prostate gland –
produce liquid with glucose for sperm.
Why?
• Urethra – carries urine & semen out of
body
4. What is the name of this process & where does
it take place?
46X
Meiosis
23X
23X
Gonads
23X
23X
5. Sexual Reproduction:
23
+
23
Egg
Sperm
Fertilization
46
Zygote
A fertilized egg cell is called a Zygote
Characteristics of Sexual Reproduction:
1) Is the creation of a new individual from 2 parents.
2) Offspring are not genetically identical to the parents.
6. Human Sexual Reproduction
• Internal fertilization – male
penis is used to introduce
sperm into female’s vagina.
7) Where does fertilization usually occur?
• Fertilization occurs in
the fallopian tubes
(oviduct)
8. How many eggs are released a
month by a female?
Normally one
egg is released
per month,
however,
sometimes
TWO can be
released at the
same time.
Ovulation
9. What happens after fertilization?
The embryo travels to the uterus
and implants itself in the uterus
lining
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How can hormones influence the
reproductive cycles in humans?
Who am I?
An Adolescent Going Through Puberty
•Our bodies change. You grow taller & bigger.
•Our sexual organs mature.
•Hair appears where there was no hair before.
•You may begin to feel attracted to another individual.
1. Control of
Reproductive Systems
The Hypothalamus &
Pituitary Gland produce
hormones that influence
the gonads to produce sex
hormones
2. Hormonal Control of the Female Reproductive System:
Beginning at puberty, female
reproductive organs undergo a
cycle of changes that prepare the
body for the possibility of
pregnancy.
Menstrual Cycle
The hypothalamus, the pituitary
gland, and the ovaries produce
hormones that control this cycle
of change.
What is this cycle of change
called?
3. Menstrual Cycle (28 Days)
•Follicular Phase (14 Days)
•Ovulation (1 Day)
•Corpus Luteum Phase (14 Days)
Menstrual Cycle Stages
a) Follicular Stage:
• FSH (follicle stimulating hormone) secreted from
pituitary stimulates the ovary to produce estrogen
• Follicle- cells that surround & protect egg.
• FSH also causes egg to mature inside a follicle
• Estrogen causes the lining of uterus to begin to
thicken
• 10-14 days
How does a woman get ready to get pregnant?
An egg is produced & the lining of the uterus thickens to
receive the embryo
b) Ovulation
•LH secreted by the pituitary increases and
the follicle bursts
•Release of an egg into the oviduct (This is
when a woman can get pregnant)
•Around day 14
c) Corpus Luteum Phase
•Broken follicle is now a corpus luteum
•Secretes estrogen & progesterone to
further thicken the lining of the uterus
•10-14 days
4. MENSTRUATION
•Occurs if there is NO fertilization
•Hormones decrease
•Uterine lining sheds
•3-7 days
5. Uterine Lining
A woman gets rid of the old uterine lining & the
unfertilized egg (if the egg is NOT fertilized)
6. Hormones & the menstrual cycle
• Which hormones
peak before
ovulation?
• Which hormone
peaks after
ovulation?
http://www.msnbc.com/ne
ws/wld/graphics/menstrual
_cycle_dw.htm
7) Girls
Secondary Sex Characteristics
•Hips widen
•Pubic Hair
•Breasts
enlarge
Due to the hormones estrogen
and progesterone.
8. Hormonal Regulation of the Testes:
• Beginning at puberty,
the pituitary gland
secretes FSH & LH.
• The rising levels of
these hormones
stimulate the testes to
produce
testosterone.
• Testosterone
stimulates the
production of sperm.
9. Boys
Secondary Sex Characteristics
• Voice Deepens
• Facial Hair
• Muscular
Development
• Pubic Hair
Due to the hormone
Testosterone.
10. What mechanism is involved in
the control of reproduction?
FEEDBACK MECHANISM
How does an embryo develop
inside the uterus?
1. How long are humans pregnant?
Females are pregnant for nine months or 38 weeks
During this time, the mother and baby undergo many
changes.
2. Embryonic Development:
Fertilization
Mitosis
+
Sperm
Egg
Zygote
Embryo- the stage in human development from the
first division of the zygote until about nine weeks
after fertilization.
3. Embryo vs. Fetus
Embryo
Fetus
(8 weeks-Birth)
(Fertilization-8 weeks)
Once the embryo becomes a fetus, all the major
organs have begun to form.
Cleavage
•The term used to describe
the early cell division
associated with embryonic
development.
•During this time period, the
number of cells increase
tremendously.
The result of cleavage is an embryo that is …..
Morula
A solid ball of cells which moves towards the
uterus
Mitosis continues & the embryo becomes……
Blastocyst
A hollow ball of cells
4. What happens after
fertilization?
The embryo travels to the uterus
and implants itself in the uterus
lining
5. Where does the embryo develop?
• In the uterus - womb
• Surrounded by an amniotic sac & fluid for
protection from shock
6. EARLY DEVELOPMENT
•Cleavage occurs by mitosis
•4 days the embryo = 50 cells
•6-7 days = 100 cells and
•attaches to the uterine wall
(IMPLANTATION)
Cell division continues & the embryo starts to ….
Gastrula • Fold inwardly
Gastrulation
• Three layers
• Each layer will eventually
form the different organ
systems
• Ectoderm (skin & CNS)
• Endoderm (GI Tract & lungs)
• Mesoderm (everything else)
7. CELLULAR DIFFERENTIATION
• Due to gene
expression, cells
undergo cellular
differentiation, in
which the cells
become
increasingly
specialized in
structure &
function.
8. What does a developing embryo need?
1. Nutrients for ATP
& to build its own
body parts
2. Oxygen for
ATP
9. Embryonic Waste Products
1. Metabolic
2. Carbon Dioxide
waste (from cells)
a. Umbilical Cord
The umbilical cord is responsible for
carrying nutrients and oxygen to the
developing fetus, and waste away.
b. Placenta
The placenta is the organ that
allows for the exchange of
nutrients and wastes
11. Fetal Blood Supply
The blood from the mom and the embryo
NEVER mix. Materials diffuse between
the mother’s blood & the babies blood.
12. Why is the fetus floating in a fluid?
The fetus is surrounded by
amniotic fluid and it helps
absorb shock
STRUCTURES BY 3rd WEEK
•Placenta
•Nervous and endocrine system (starting)
•Vital organs forming
•Heart is beating
FIRST TRIMESTER
•Most major organs formed
•Umbilical cord formed
•Muscular system developed
•Reflexes
•Amnion formed
SECOND TRIMESTER
•Tissues become specialized
•Skeleton forms
•Strong fetal heartbeat
•At ~6 months the baby can live outside the
mom with life support
3rd Trimester
•Fetus doubles in size
•Lungs are forming
•Sleeps 90-95% of the time
•Dreams
•Premature if born before 8 months
13. What happens at around 9 months?
The fetus has developed all its
organs and is ready to live in
the outside world
The uterine muscles begin to
contract and the baby is
forced out of the mother.
This process is called: Labor
14. Prenatal care
• Good nutrition
• Moderate exercise
• No smoking
• No drugs, prescription or
illegal
• No alcohol
Don’t get morning sickness: Thalidomide
(1950)
Fetal Alcohol Syndrome (FAS)
Consuming
alcohol during
development can
cause FAS which
has disastrous
affects on the
CNS.
15. What trimester is the
most dangerous?
The first trimester, because all the organs
are forming at this time. Dangerous
chemicals can affect cell division.
Aim: How have organisms benefited
from reproductive technology?
1. What is Reproductive Technology?
1) Methods that assist organisms to produce offspring.
2) Methods that aid in the examination of developing
offspring.
2. Why might some people need reproductive
technologies?
Some people cannot become
pregnant because of problems
with their hormones, ovaries,
testes, or other parts of their
reproductive systems.
Infertility – cannot produce
offspring.
3. Applications of Reproductive Technology:
Medical Applications:
1) In-Vitro Fertilization
2) Artificial Insemination
3) Cloning??
4) Amniocentesis & Karyotyping
a) In-Vitro Fertilization
Sperm fertilizes egg in a test tube
The embryo is then….
Implanted into a
mother’s uterus.
b) Artificial Insemination
Inserting sperm inside
females fallopian tube
How do we store sperm, eggs &
embryos for in-vitro fertilization?
Frozen in a bank
c) Cloning
Take nucleus from individual who
will be cloned & insert it into an
anucleated egg
Why Clone?
d) Amniocentesis & Karyotpying
Amniotic fluid is withdrawn from a
woman's uterus to test for certain
problems in the fetus, such as genetic
defects.
4. Sonograms - Ultrasound
Use of sound and echo to create an
image of the developing embryo
Applications of Reproductive Technology:
Agriculture:
1) Scientists have genetically modified plants using DNA
Recombinant Technology to be resistant to disease. These
modified plants can then be cloned to produce thousands
of genetically identical offspring.
2) Using artificial insemination, scientists can generate
hundreds of offspring from one farm animal.
3) Selective Breeding
Selective Breeding
To obtain organisms with desired traits
Meaty cow
Milk producing cow
Applications of Reproductive Technology:
Ecology:
1) Embryos from endangered species have been transplanted
into related species, who later give birth to offspring that
are no different than they would be if they developed in
the bodies of the endangered species themselves.