Transcript Endocrine System - ABC-MissAngelochsBiologyClass

SORRY!
Function of the Endocrine
System….
 Chemical Regulation
 Stimuli  Glands  Secrete
Hormones  Response
 Includes:
Endocrine
glands and
their hormones
 Endocrine glands secrete hormones
directly into the bloodstream
 Hormones are chemical messengers
that cause other body parts to
respond
 Hormones are very specific and can
only bind to the receptors of target
cells or tissues
#3 Pituitary- the ‘master
gland’
- Releases secretions that control all the other
glands. Turned on by the hypothalamus.
(part of the brain)
 Growth hormone (hGH)
 Stimulates the growth of long bones
 Also regulates other glands
Pituitary Gland cont.
 Luteinizing hormone (LH)
 Causes release of egg cells. Controls
production of sex hormones in men and
women
 Follicle-stimulating hormone (FSH)
 Function: stimulates production of egg
and sperm cells
Growth Hormone Diseases
 Hypersecretion (too
much secretion)
Giantismexcessive growth
about normal size
 Andre the Giant
(7’4” 500 lbs)
 Hyposecretion
(too little
secretion)
Dwarfism–
person doesn’t
grow taller than 4
feet
#4 Thyroid
Thyroxin
- Regulates Metabolism
Calcitonin
- Regulates blood calcium levels
MOOOO!!!
Thyroxin Diseases
 Hypersecretion- nervousness,
weightloss, sleeplessness
 Hyposecretion: Mental retardation,
weight gain
Goiters
 A swelling of
the thyroid
gland
 Caused by
iodine
deficiency
#5 Parathyroid Parathormone
 Function:
 Controls
calcium
metabolism
 Necessary for
normal nerve
and muscle
function, blood
clotting,
healthy bones
and teeth
Parathormone Diseases
 Hyposecretion: Nerve disorders,
brittle bones, clotting problems
#7 Adrenal
 Cortisone and
Adrenaline
 Function:
 Cortisone: regulates
nutrient metabolism
 Adrenaline:
increases heart rate
and breathinghandles sudden
stress
 Adrenaline Disease
 Hyposecretion: inability to deal with
stress
 Cortisone Disease
 Hypersecretion: Cushing’s disease
(high blood glucose, excess fat)
 Hyposecretion: Addison’s disease
(low blood glucose, weight loss)
#8- Pancreas
 Hormones: Insulin
and Glucagon
 Insulin:
stimulates uptake
of glucose by
cells.
 Glucagon:
converts
glycogen to
glucose
 Insulin Disorders
 Hypersecretion: Low blood
sugar
 Hyposecretion: diabetes (high
blood sugar)
 Glucagon Disorders
 High blood sugar
#9 Ovaries
 Estrogen
 Stimulates development of female
reproductive system and sex
characteristics
 ex: Wider hips, breasts, menstrual cycle
#10 Testes
 Testosterone
 Stimulates development of male
reproductive system and sex
characteristics
 ex: deep voice, beard, body hair
Feedback Mechanisms
A feedback mechanism occurs when the
level of one substance influences the level
of another substance or activity of another
organ. (chain of reactions)
It can increase the production of
something (positive feedback) or it can
decrease or stop the production of
something (negative feedback)
 Internal feedback system that regulates
the endocrine system (controls the
amount of hormones in the blood)
 Works like a thermostat in your home.
The room is maintained at a certain
temp. When the temp. drops the heat
kicks in. When it starts to get hot it slows
production.
 *** This helps to maintain homeostasis
high blood
sugar
pancreas
secretes
less insulin
pancreas
secretes
more insulin
low blood
sugar