Transcript Endocrine
The Endocrine System
Are your hormones runnin’ wild?
Glands
Exocrine - Secrete into ducts or onto a
free surface - sweat, sebaceous,
mucous, digestive
Endocrine - secrete into cellular space
then into blood - hormones
Hormones
Hormones are chemical messages
Regulate the chemical composition and
volume of the internal environment
What are some examples of regulation of
chemical composition of blood. How about
volume
Glucose, Water
Regulated by insulin and a hormone called ADH
(antidiuretic hormone)
Hormones
Help regulate organic metabolism and energy
balance
Thyroid gland
Help body cope with emergency environmental
demands - infection, trauma, emotional stress,
dehydration, starvation, hemorrhage, and
temperature extremes.
Adrenaline (epinephrine)
Fight or flight syndrome
Sympathetic
Hormone producing cells are sent
information from sensing and signaling
systems - permit regulation of amount
and duration of hormone release
Examples: Blood glucose, Na+, K+, Ca++,
O2
Target cells - cells that are affected by specific
hormones
Receptors - most cells have receptors that
bind to one or more hormones
There are about 50 different hormones - cells
only respond to specific hormones
Once a hormone binds to a cell’s receptors,
there is a set of reactions within the target cell
to produce the desired effects
Feedback Systems
“Circular situation in which information
about the status of something is
continually reported (fed back) to a
central control region.”
Like a thermostat.
Negative feedback system - reverses the
direction of the initial condition
Negative - response is opposite to the
stimulus
Hypothalamus
Thalamus
Pituitary Gland
Thyroid
Parathyroids
Pancreas
Thymus
Adrenals
Ovaries
Testes
Posterior Pituitary
ADH (Anti-Diuretic Hormone)
Controls Kidneys
Oxytocin
Stimulates mammary glands to produce milk
Stimulates uterine contractions
Anterior Pituitary
HGH (Human Growth Hormone)
Stimulates cell division, protein synthesis,
bone growth
Prolactin
Milk production
MSH (melanocyte-stimulating hormone)
Skin color in lower verts, unknown in humans
Anterior Pituitary
TSH (Thyroid Stimulating Hormone)
Stimulates thyroid
ACTH (adrenocorticotropic hormone)
Stimulates adrenal cortex
Gonadotropic Hormones
Gamete and sex hormones
Thyroid
Thyroxin
Increases metabolic rate
regulates growth and development
Calcitonin
Lowers blood Calcium levels
Parathyroid
PTH
Raises blood Calcium levels
Adrenal Medulla
Epinepherine and Norepinephrine
Adrenaline
Cardiac and other muscles
Adrenal Cortex
Glucocorticoids
Raise blood glucose level, stimulates
breakdown of protein
Mineralcorticoids
Stimulates kidneys to reabsorb sodium and
excrete potassium
Sex Hormones
puberty
Pancreas
Insulin
Lowers blood glucose
Promotes formation of glycogen, proteins, fats
Glucagon
Raises blood glucose
Promotes breakdown of glycogen, proteins, fats
Gonads
Testes
Androgens (Testosterone)
Stimulates spermatogenesis
Develop and maintain male characteristics
Ovaries
Estrogen and Progesterone
Growth of uterine lining
Develop and maintain female characteristics
Thymus
Tymosins
Stimulates maturation of T Lymphocytes
Disorders of Endocrine Glands
Diabetes Mellitus: Insulin Lack and Insensitive
Cells
Symptoms:
Sugar in urine
Frequent urination
Abnormal thirst
Rapid Weight Loss
Itching
Visual Disturbances
Skin disorders - boils, infections
Diabetes
Sugar is not being metabolized
Liver fails to store glucose as glycogen
Cells fail to utilize glucose efficiently
Body turns to breakdown of protein and
fats