The
Endocrine
System
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The Endocrine System
• The body’s slow chemical communication
system; a set of glands that secrete
hormones into the blood stream.
– Nervous system = fast, transient
– Endocrine system = slow, sustained
• Secrete directly into blood capillaries
– Exocrine glands secrete into ducts (tubes)
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The Endocrine System
A Brief List of 5 Glands
1. Thyroid gland- affects metabolism
2. Pancreas – regulates the level of sugar in
the blood
3. Parathyroids – help regulate the level of
calcium in the blood
4. Ovary – secretes female sex hormones
5. Testes – secrete male sex hormones
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The Endocrine System
A Set of Glands
The Pituitary Gland
A sort of “master gland”
It is cherry-sized endocrine gland
The hormones it secretes affect growth and the
secretion of other endocrine glands
The real boss is the hypothalamus
Feedback System
brain
pituitary
other glands
hormones
brain
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The Endocrine System
A Set of Glands
The Adrenal Gland
A pair of endocrine glands just above the
kidney
They secrete epinephrine and norepinephrine
which help to arouse the body in times of
stress.
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Lateralization of the brain is
under hormonal control
Left Hemisphere
Verbal competence
Speaking, reading,
thinking & reasoning
Processes info in
sequence
One piece of data at a
time
logical
Right Hemisphere
Nonverbal areas
Comprehension, spatial
relationships,
drawing, music,
emotion
Processes info. As a
whole
intuitive
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Emotion and Lateralization
Left Hemisphere
• Important for the
expression of positive
emotion
• Damage to the L.H.
leads to loss of the
capacity for joy.
• Activation in the L.H.
leads to tendencies to
approach other people.
Right Hemisphere
• Important for the
expression of negative
emotion
• Damage to the R.H. may
make people euphoric.
• Activation in the R.H.
leads to tendencies to
withdraw from people.
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Youtube
• https://www.youtube.com/watch?v=nNLsXKkL
STs
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Youtube
• https://www.youtube.com/watch?v=iDy_p9912a
o
• https://www.youtube.com/watch?v=n2GgOYO9
QZM
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Believed true
until 1865
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Survey of 5000 entering college
freshmen in Texas, New York and
Canada, 1999
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•
•
•
2500 females asked about typical male brain
2500 males asked about typical female brain
No other instructions
Average of all responses
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It’s a joke, get over it!
Those were the results!
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It’s a joke, get over it!
Those were the results!
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Important Hormones
Insulin
Produced by the pancreas
Regulates the body’s use of glucose & affects
appetite
Melatonin
Secreted by the pineal gland
Helps to regulate daily biological rhythms and
promotes sleep.
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Hormones
Adrenal Hormones
Produced by the adrenal glands are involved in
emotion and stress. They rise in response to
nonemotional conditions, such as cold, heat, pain
injury, and physical exercise, and in response to
some drugs such as caffeine and nicotine.
The Outer Part (Cortex)
Cortisol
The Inner Part (Medulla)
Epinephrine & Norepinephrine
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Hormones
Sex Hormones
Are secreted by the gonads and by the adrenal
glands
Androgens
Masculinizing Hormones
Estrogens
Feminizing Hormones
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Neurotransmitters & Hormones
Acetylcholine
Shortage in acetylcholine may be associated with
Alzheimer’s disease
Dopamine
The degeneration of brain cells that produce and use
another neurotransmitter, dopamine, appears to
cause symptoms of Parkinson’s disease.
Low levels of dopamine may cause ADHD
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Neurotransmitters & Hormones
Serotonin
Decrease in norepinephrine and serotonin is
associated with depression. Elevated levels along
with other biochemical and brain abnormalities
have been implicated in childhood autism.
Norepinephrine
Norepinephrine, epinephrine, and adrenaline are
associated with excitement and stress.
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Neurotransmitters & Hormones
Cortisol
Cortisol is associated with stress. Increase in cortisol
damages the brain and may be associated with
posttraumatic stress.
GABA
Abnormal GABA levels have between implicated in sleep
and eating disorders and in compulsive disorders.
Glutamate
Glutamate, serotonin, and high levels of dopamine have been
associated with schizophrenia
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