3. Functions:
Tropic hormones (stimulate growth), sex hormones (target reproductive tissues), and anabolic
hormones (stimulate anabolism in their target cells) are all hormones classified by their general
functions.
Structures:
Hormones get classified by their chemical structure
Steroid Hormones:
Manufactured by endocrine cells from cholesterol, an important type of lipid in the human body.
Because steroids are lipid soluble, they can easily pass through the phospholipid plasma membrane of
target cells.
Non-steroid Hormones:
Synthesized primarily from amino acids rather than from cholesterol. Some are protein hormones; they
are long folded chains of amino acids, and a structure type of protein molecules of any sort.
How do Hormones work?
1. Lock and Key: The amino acid structure of the hormone is the key and the receptor is a lock. In
order for the key hormone to fit in the lock receptor, the hormone –receptor complex must be
an exact match.
2. What happens when hormones combine? : A specific hormone combines with a specific
receptor site, and forms a combination and a reaction of both.
5. Hormones: Insulin and Glucagon
Gonads- Function: Produces gametes
Location: Testes in males, Ovaries in Females
Hormones: Gametes
Placenta- connects fetus to utirne wall, produces pregnancy related hormones, including chorionic
gonadotropin, estrogen, and progesterone.
Thymus- located in upper chest, underneath breast bone, helps the body make white blood cells that
help fight against infections
Gastric and intestinal mucosa- allow efficient transport of nutrients across the epithelium while
excluding passage of harmful molecules and organisms, located in a layer of the stomach
Heart- pumps oxygen-rich blood to every living cell in the body, non-beating heart results in death, the
heart beats approximately 80,000 to 100,000 pumps per day. it is located in the chest. Blood is pumped
through arteries, it is all a continuous cycle. Hormones Chart
Hormone Source Target Principal Action
Growth hormone Hypothalamus Adenohypophysis Stimulates secretion of
releasing hormone (somatotrophs) growth hormone
(GRH)
Growth hormone- Hypothalamus Adenohypophysis Inhibits secretion of
inhibiting hormone (somatotrophs) growth hormone
(GIH) or somatostatin
Corticotropin-releasing Hypothalamus Adenohypophysis Stimulates release of
hormone (CRH) (corticotrophs) ACTH
Thyrotropin-releasing Hypothalamus Adenohypophysis Stimulates release of
hormone (TRH) (thyrotrophs) TSH
Gonadotropin-releasing Hypothalamus Adenohypophysis Stimulates release of
hormone (GNRH) (gonadotrophs) (FSH) and (LH)
Prolactin-releasing Hypothalamus Adenohypophysis Stimulates secretion of
hormone (PRH) (coritcotrophs) prolactin
Prolactin-inhibiting Hypothalamus Adenohypophysis Inhibits secretion of
hormone (PIH) (corticotrophs) prolactin
Growth hormone Adenohypophysis General Promotes growth by
somatotropin (STH) (somatotrophs) stimulating protein
anabolism and fat
mobilization
Prolactin (PRL) Adenohypophysis Mammary Glands Promotes milk secretion
(lactotrophs)
Thyroid-stimulating Adenohypophysis Thyroid Gland Stimulates
hormone (TSH) (thyrotrophs) development and
secretion in the thyroid
gland
ACTH Adenohypophysis Adrenal Cortex Promotes development
(corticotrophs) and secretion in the
6. adrenal cortex
Follicle-stimulating Adenohypophysis Gonads Female: promotes
hormone (gonadotrophs) development of ovarian
follicle, simulates
estrogen secretion
Male: promotes
development of testis;
stimulates sperm
production
Luteinizing hormone Adenohypophysis Gonads Female: triggers
(LH) (gonadotrophs) ovulation; promotes
development of corpus
leteum
Male: stimulates
production of
testosterone
Antidiuretic hormone Nuerohypophysis Kidney Promotes water
(ADH) retention by kidney
tubules
Oxytocin (OT) Nuerohypophysis Uterus and mammary Stimulates uterine
glands contractions; stimulates
ejection of milk into
mammary ducts
Triiodothyronine Thyroid gland (follicular General Increases rate of
cells) metabolism
Tetraiodothyronine or Thyroid gland (follicular General Increases rate of
thyroxine cells) metabolism usually
converted to T3 first
Calcitonin Thyroid gland Bone tissue Increases calcium
(parafollicular cells) storage in bone,
lowering blood Ca ++
levels
Parathyroid hormone Parathyroid glands Bone tissue and kidney Increases calcium
(PTH) removal from storage in
bone and produces the
active form of vitamin D
in the kidneys
Aldosterone Adrenal cortex (zona Kidney Stimulates kidney
glomerulosa) tubules to conserve
sodium- release of ADH
Cortisol Adrenal cortex (zona General Influences metabolism
fasciculate) of food molecules
Adrenal Androgens Adrenal cortex (zona Sex organs May support sexual
reticularis) function
Adrenal estrogens Adrenal cortex (zona Sex Organs Insignificant
reticularis)