Zoology CTD
Terms
undefined, object
copy deck
- Functions to regulate the metabolic activity of cell.
- Endocrine System
- No ducts to transport secretions. Secrete hormones(chemical messengers) which are transported by blood to target organs.
- Endocrine glands
- Small compared to other organs: all endocrine tissue from 8-9 adults would wigh only
- 1 kg or 2.2 lbs
- Steroid hormone or Thyroid Hormone act by this method.
- Nuclear Receptors
- Protein Hormones
- Membrane Bound Receptors
-
Nuclear Receptors:
Hormone crosses the ____
Binds to ___
Hormone/receptor complex enter the _____
Activates or inhibits_____ -
Plasma Membrane
Intracellular Receptor
Nucleus
Transcription- mRNA synthesis -
Membrane Bound Receptors:
Bind to ______
HOrmones are 1st messengers and activate 2nd messenger system in ___
2nd Messenger (cAMP) activates a specific ______ which activates or inactivates enzymes -
Cell surface receptor
Cytoplasm
Kinase - Regulates most hormonal secretions; output of the system TURNS OFF the orginal stimulus; Goal is to prevent sudden and severe chagnes within the body
- Negative Feedback System
- Result of response enhances the original stimulus so that the activity (output) is sped up.
- Positive Feedback System
- Produces inhibiting and releasing hormones that regulate activity; produces ADH and Oxytocin
- Hypothalamus
-
___ increase H2O reabsorption by kidney.
______ increase uterine smooth muscle; stimulus milk ejection in nursing mothers -
ADH- antidiuretic hormone
Oxytocin -
Pituitary Gland: (Hypophysis)
have 3 lobes _______ - Adenohypophysis: Anterior Lobe, Intermediate Lobe, Neurohypophysis: Posterior Lobe
- Extremely Tall; long arms and legs; in children
- Gigantism(hypersecretion of growth hormone)
- Increase width of bones not length; broad face/hands/feet; overgrowth of soft tissues-deep furrows in face; in adults
- Acromegaly(hypersecretion of GH)
- Extremely short; normal limb length to body thorax length; in children
- Pituitary Dwarfism (hyposecretion of GH)
- Increase BMR; required for normal development of NS
- Triiodothyronine (T3) and Thyroxine (T4 or Tetraiodothyronine
- decrease blood
- Calcitonin
- Short stature, profound Mental Retardation
- Cretinism (hyposecretion in children)
- Lethargic, intolerant of cold, dry skin and hair, weight gain, simple goiter(enlarged thyroid)
- Myxedema(form of hypothyroidism and hyposecretion in adults)
- Increase BMR, intolerant of heat, expothalmic goiter, inability to concentrate, weight loss
- Graves' Disease (form of hyperthyroidism and hypersecretion in adults)
- t3 or t4 disorders
- Cretinism, Myxedema, Graves' Disease
- hormone imbedded in thyroid
- parathyroid horomone
- increase blood, Ca+2 removed from bone
- parathyroid hormone
- Hypocalcemia leads to tetany: loss of sensation, muscle twitches, convulsions
- Hypoparathyroidism
- Rare, Osteitis cytica fibrosa (severe) bones have a moth-eaten app and fracture easily
- Hyperparathyroidism
- Regulate Glucose metabolism and inhibits inflammatory and immue response, assist body to resist stressors
- Glucocorticoids (cortisol, cant live without these)
- Increase Na+ absorption, increase H2) reabsorption, increase blood volume and pressure
- Mineralocorticoids (aldosterone)
- limited secretions here, usually of no consequence in adults
- Adrenal Sex Hormones
- Enhance the response of sympathetic NS
- Epinephrine, NOrpinephrine
- COrtex Adrenal Glands:
- Glucocorticoids, Mineralocorticoids, Aderanl Sex Hormones
- medulla adrenal glands:
- epinephrine, norepinephrine
- increase blood glucose levels, alpha cells
- Glucagon
- Decreases blood glucose levels, beta cells
- Insulin