THE ENDOCRINE
SYSTEM
The Endocrine System
Made up of:
1. Glands
• secrete hormones
2. Organs
Glands
Function of The Endocrine System
1. Regulates
metabolism, growth,
and mood
2. Maintains
homeostasis
3. Establish circadian
rhythms
4. Responds to stress
Endocrine Glands vs Exocrine Glands
Exocrine Glands
•Secrete products
that go out of the
body
•Ex.
Endocrine Glands
•Secrete hormones
in the body
•Diffuse in
Endocrine Glands
Pituitary
• Makes hormones that control
other glands
Thyroid
• Controls metabolism and rate at
which cells burn fuel
Parathyroid
• Regulate the level of calcium
and phosphorous
Adrenal
• Control fight or flight response,
anti-inflammatory response and
regulation of salt and water
Endocrine Glands
Pineal Glands
• Control your circadian rhythm
Hypothalamus
• Links the endocrine glands
and the nervous system
Thymus
• Helps fight infection with the
aid of T-cells.
Pancreas
• Maintains a steady level of
glucose in the body
Endocrine Glands
Ovaries
• Found only in women
• Responsible for regulating
menstruation and for
secondary sex characteristics
Testes
• Found only in males
• Responsible for secondary
sex characteristics
Hormone Action
Endocrine system
communicates with the
body by:
• Releasing hormones into
blood stream
• Target bind to receptor
• Hormone binds = body
responds
*****Proteins attach and control
the amount of hormone available
Hormones
• chemical messengers
• Act on target cells (organs)
Hormone Action
7. Why were some of the actions on the cards the same? Hint:
think about how you found your match?
Hormone Release
Occurs when:
1. Signaled from
nervous system
2. Chemical
changes in blood
3. Other hormones
Continued
•Stimulation causes
release
increase
of the hormone
Stimulation Stops:
• Hormone levels decrease
OR
• Is inactivated or excreted
Dehydration
• Blood volume falls and
osmotic blood pressure
rises
ADH is released
Body retains H 2O
What happens?
• High osmotic blood
pressure
High osmotic blood pressure
Blood Calcium Levels
High Blood Ca+ Levels
Calcitonin is released
Osteoclast action is
inhibited
(bone not broken down)
Blood Calcium is
lowered
Low Blood Ca+ Levels
Parathyroid hormone is
released
Increase in osteoclasts
activity
Blood calcium levels
increase
Regulation of Blood Glucose Levels
Low blood glucose
High Blood Glucose
Glucagon released
Insulin released
Glycogen breaks down
to glucose
Glucose moves into cells
Glucose levels increase
Glucose levels decrease
Most hormones work via Negative
Feedback
Hormones and Positive Feedback
The Stress Response
Stress
• Cause by stimulus
Stages
1. Fight or flight
2. Resistance reaction
3. Exhaustion
Stress???
Fight or Flight
• Triggered by nerve
impulses
• Very short stage
How does the body
respond?
• Most body systems
increase
• Some decrease
• https://www.youtube.com/watch?
v=m2GywoS77qc
Resistance
• Cells are supplied with
ATP
• Body can continue the
“fight”
Exhaustion
• Resources are depleted
• Body can’t fight stressor
Stress Response Comic Story Board
• You and your group will create a story board that
depicts the stress response in the body
• The Your story board should convey the details of
each stage.
• At the end of class you will combine your efforts
into one document (a story board)
• Use color
• Get creative with it
Sleep
Regulated by two
systems
1. Sleep/wake
homeostasis
2. Circadian rhythm
(biological clock)
Sleep needs
• Based on age
http://www.youtube.com/watc
h?v=jFfAbMbrZrA
Circadian Rhythms
(Continued)
• What do circadian
rhythms regulate?
• What effects can
changing your sleep
cycle have on the
body?
• What is delayed sleep
phase disorder?
• What can you do to
“reset” your internal
clock?
The Sleep Cycle
Stage 1
• Light sleep (5-10 min)
• Easily woken up
• “Falling” sensation
Stage 2
• Heart rate slows
• Body temp drops
• Breathing regular
The Sleep Cycle
Stage 3
• Deepest Sleep
• HGH secreted
• Tissue repair
REM
REM
• Brain looks like it is
awake
• Vivid dreams
• Muscles are
paralyzed
Sleep stages are not
sequential
The Need For Sleep Campaign
PSA
Https://www.youtube.com/watch?v=rClJW9gnchc
https://www.youtube.com/watch?v=5Z_zWIVRIWk
Political AD
https://www.youtube.com/watch?v=7F6PBldQxZc
https://www.youtube.com/watch?v=fYw1VPI--Yk