Download Endocrine Quiz Review

Endocrine System Quiz Info
-Endocrine System-prolonged effects via hormones
**Endocrine organs are DUCTLESS
-Endocrine organs: pituitary, thyroid, parathyroid, adrenal and pineal gland.
-Neuroendocrine organ: Hypothalamus
-Autocrines: Act on cells that secrete them vs. Paracrines: Act on cells nearby
-Endocrine glands become less effective with age
Hormones: Steroid or amino acid based
-Stimulate or inhibit target cell
-Mechanisms: alter membrane permeability, enzyme synthesis, secretion, and mitosis
-Many interact with second messenger mechanisms (G Proteins)
-Ability for hormone to interact with target cell depends on membrane receptors
-Activated by HUMORAL, NEURAL & HORMONAL stimuli, also NEGATIVE FEEDBACK
-HYPOTHALAMUS is control of endocrine system via the nervous system
Interaction Types:
1. Permissiveness: one hormone must be present for another hormone to have full effect
2. Synergism: 2 or more hormones produce same effect and together amplify effect
3. Antagonism: a hormone opposes/reverses the effect of another
Pituitary/hypothalamus Relationship
-Hypothalamus synthesizes and exports hormones to the posterior pituitary and regulates
the hormonal output of the anterior pituitary
-POSTERIOR PITUITARY: Stores and releases OXYTOCIN (stimulates uterine contractions
and milk release) and ADH (stimulates renal tubules ot reabsorb and conserve water)
-ANTERIOR PITUITARY: Releases GH (stimulate growth of skeletal muscle regulated by
GHRH & GHIH), TSH (thyroid gland development, regulated by TRH and TSH), ACTH
(stimulates Adrenal cortex to release corticosteroids), FSH (stimulates sex cell production,
regulated by GnRH), LH (stimulates gonadal hormone production, regulated by GnRH),
PRL (promotes milk production)
Thyroid Gland
-T4 and T3 increase the rate of cellular metabolism
-Most T4 is converted to T3 (more active form). Act by turning on gene transcription and
protein synthesis
Parathyroid Gland
-Secrete PTHincreases blood calcium levels**
-Falling blood calcium triggers PTH release, high levels blood calcium inhibit PTH release
The Adrenal Gland
1. Adrenal Cortex: Produces three steroids–Mineralocorticoids (aldosterone),
Glucocorticoids (cortisol), Gonadocorticoids (androgens)
2. Adrenal Medulla: Produces catecholamines (epinephrine and norepinephrine)
Other Endocrine Glands/Tissue to Know
Endocrine System Quiz Info
-PANCREAS: release insulin (beta cells-released when blood glucose is HIGH) and
glucagon (alpha cells-released when blood glucose is LOW)
-GONADS: Associate with FSH and LH