lOMoARcPSD|268163 03
Hormones as Long-Term Controllers
•
Hormones typically regulate activities that occur over an extended period
•
Nervous system signals control rapid-reflexes and speedy responses to changing conditions
inside or outside the body
•
Endocrine system specializes in slower, often long-term bodily changes such as growth,
sexual maturation, production of red blood cells
•
Some of these functions involve hormones from the hypothalamus and pituitary, while
others depend on other sources
Hormone Sources other than the Hypothalamus and
Pituitary
Source
Secretion(s)
Main Targets Primary Actions
Source
Secretion(s)
Main Targets Primary Actions
Pancreatic
islets
Insulin
Muscle, adiposeLowers blood-sugar level
tissue
Glucagon
Liver
Raises blood-sugar level
Somatostatin
Insulin-
Influences carbohydrate
secreting cells
metabolism
Adrenal
Glucocorticoids
Most cells
Promote protein breakdown and
cortex
(including cortisol)
conversion to glucose
Mineralocorticoids
(including
aldosterone)
Kidney
Promote sodium reabsorption;
control salt-water balance
Adrenal
Epinephrine
Liver, muscle,
Raises blood level of sugar, fatty
medulla
(adrenaline)
adipose tissue
acids; increases heart rate,
force of contraction
Norepinephrine
Smooth muscle Promotes constriction or dilation
of blood vesselsof blood vessel diameter
Thyroid
Triiodothyronine,
thyroxine
Most cells
Regulate metabolism; have
roles in growth, development
Calcitonin
Bone
Lowers calcium levels in blood
Parathyroids
Parathyroid
hormone
Bone, kidney
Elevates levels of calcium and
phosphate ions in blood
Thymus
Thymosins, etc.
Lymphocytes
Have roles in immune responses
Gonads:
Testes (in
Androgens
General
Required in sperm formation,
males)
(including
testosterone)
development of genitals,
maintenance of sexual traits;
influence growth, development
lOMoARcPSD|268163 03
Source Secretion(s) Main Targets Primary Actions
Source Secretion(s) Main Targets Primary Actions
Ovaries (in
females)
Estrogens
General
Required in egg maturation and
release; prepare uterine lining
for pregnancy; required in
development of genitals,
maintenance of sexual traits;
influence growth, development
Progesterone
Uterus, breasts Prepares, maintains uterine
lining for pregnancy; stimulates
breast development
Endocrine
cells of
stomach, gut
Gastrin, secretin,
etc.
Stomach,
pancreas,
gallbladder
Stimulate activity of stomach,
pancreas, liver, gallbladder
Kidneys
Erythropoietin
Bone marrow
Stimulates red blood cell
production
Vitamin D
Bone, gut
Enhances calcium resorption
and uptake
•
What kinds of bodily activities do hormones typically regulate?
o Hormones generally regulate slower, often long-term changes in the growth or
functioning of body parts
2
Heart
Atrial natriuretic
peptide
Kidney, blood
Increases sodium excretion;
vessels
lowers blood pressure
Angiotensin
Adrenal cortex, Helps control blood pressure,
arterioles
aldosterone secretion
Liver
IGFs (insulin-like
growth factors)
Most cells
Stimulate cell growth and
development
Pineal
Melatonin
Hypothalamus Influences daily biorhythms
