What is REGULATION? Types of Hormones

5/7/2015
What is REGULATION?
• Life process that coordinates and
controls the life functions within an
organisms.
• Two forms of regulation:
– CHEMICAL
– NERVOUS
Differentiate between Nervous and
Chemical by filling out your Venn
Diagrams charts.
Think:
•Length of time
•Area
involved/Target
•Medium of
communication
Regulation by chemical messengers
endocrine gland
neurotransmitter
axon
hormone carried
by blood
receptor proteins
receptor proteins
target cell
Types of Hormones
• Protein-based
– Examples: insulin, FSH, LH, ADH, Epinephrine,
melatonin
– Cannot pass the membrane
– Bind to cell membrane on RECEPTORS, start a
cascade of reactions that initiate a response.
• Lipid-based (steroids)
– Examples: estrogen, testosterone
– Can pass through membrane (lipid-soluble)
– Bind to receptors inside the cell/nucleus, turn
on/off genes
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Animation 1: McGrawHill
Animation: Protein Based Hormones
Animation 2: McGrawHill
Maintaining homeostasis:
FEEDBACK
1. NEGATIVE FEEDBACK
_____________ Feedback
Mechanism
– Homeostatic control mechanisms
– Goal: change variable back to its
original/preferred state, reduce stimulus
– Example: blood sugar regulation, body
temperature regulation
2. POSITIVE FEEDBACK
– Homeostatic control mechanisms
– Goal: reduce the preferred state and
enhance the stimulus
– Example: child birth, blood clotting,
_____________ Feedback
Mechanism
_____________ Feedback
Mechanism
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Glucose Tolerance Test
For each structure following,
know the…
Name
Location
Drawing
Function
Where the Nervous & Endocrine
System Meet…
• Hypothalamus
– Part of the brain
– Master Nerve Control Center
– Secrete releasing factors/hormones that
control the release of other hormones.
• Ex: Growth Hormone-releasing hormone
(GHRH), Dopamine
• Pituitary Gland
– GLAND within the brain
– Master Gland
– Secrete stimulating hormones.
Pituitary Gland: master gland
Posterior Pituitary
When things go wrong…
Anterior Pituitary
link
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link
Thyroid: regulating metabolism
How?
• Regulated by hypothalamus
(TRH)
• Stimulated by TSH by
pituitary
Purpose?
• Regulates metabolism and
development
• Hormone: THYROXINE
When things go wrong…
• Goiter
– Enlarged thyroid gland
– Cause: iodine deficiency leading to
hyper/hypothyroidism.
– Digestion, reproduction,
bone/muscle growth, energy
level… etc.
• Hormone: CALCITONIN
– Lowers blood calcium levels,
forces excess Calcium into
bones
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Parathyroid Gland
Pineal Gland
Purpose?
• Regulates circadian
rhythms
• Role in the animal
kingdom: sexual
development,
hibernation, seasonal
breeding
• Hormone: Melatonin
Thymus Gland
Purpose?
• Maturation of immune system cells
• Hormone: Thymosin
• Stimulates the production of Tcells.
Purpose?
• Maintain calcium
levels in body for
nervous and
muscular system
• Hormone:
Parathyroid,
– Raises blood calcium
levels, even at the
expense of the
strength of your bones
Adrenal Gland
Purpose?
• Maintain homeostasis
in times of stress
• Hormone:
• Short term stress
• Epinephrine
• norephinephrine
• Long term stress
• Corticoid steroids
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Pancreas
blood sugar regulation
• Types
– I: Autoimmune
• Beta cells attacked by
immune system
• Little to no insulin made
• Insulin-dependent
diabetes
– II: Diet related
• Cells less sensitive due
to frequent and large
release of insulin.
• body cannot use the
insulin it is making
• Non-insulin dependent
diabetes*
Diabetes mellitus
Dr. Oz explains it…
Effects of high blood sugar on the body
Diabetes & Leg Amputation
– Gestational
• Insulin receptors do not
function properly
• Increase weight of
baby
• Damage to mother’s
blood vessels, increases
risk of diabetes later in
life.
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Ovaries
Purpose?
• Regulates female
menstrual cycle,
prepares/maintains
pregnancy, creates the
female appearance
• Hormones:
• Estrogen
• Secondary sex
characteristics
• Egg production
• Progesterone
• Prepares uterus for
possible pregnancy
Purpose?
• Regulates production of
sperm, appearance of
mature adult male.
• Hormones:
• Testosterone
• Secondary sex
characteristics
• Sperm
production/maturation
Testes
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