Anatomy25

  1. Endocrine System
    • Series of ductless glands that secrete hormones
    • Hormones travel to regions of body and signal physiological responses
    • Slower response than nervous system
  2. Endocrinology
    • The study of hormones and endocrine glands
    • Endocrine organs and hormones = system
  3. Exocrine Glands
    • Have ducts
    • Secrete onto body surface or into cavity
    • Secretions travel directly onto target
    • Secretions are fluids, lubricants, enzymes
    • Sweat, salivary, mucous
  4. Endocrine Glands
    • Ductless
    • Secrete hormones
    • Function id regulation, homeostasis
    • Hormones dumoed right into bloodstream, act on target cells
  5. Pure endocrine Organs
    Pituirtary Gland, pineal gland, thyroid gland, parathyroid glands, and adrenal gland
  6. Endocrine organs together in body systems
    Pancreas, thymus, gonads, and hypothalamus
  7. Hormone Classes
    Amino Acid (protein) or steroid (lipid)
  8. Hormone Action
    • Circulate through bloodstream and affect only the target cells
    • Hormones themselves are just triggers
  9. Hormone secretion control
  10. Humoral Stimuli
    Respond to changing levels of ions/nutrients in blood
  11. Neural Stimuli
    Respond to nervous system
  12. Hormonal Stimuli
    Respond to hormones from other glands
  13. Feedback Loops
    • Negative= more hormone secretion if level drops
    • Positive= more hormone secreted if levels increase
  14. Pituitary Gland
    • 9 major proteins from 2 portions
    • All protein hormones
    • Small/ round structure
    • On stalk below hypothalamus
    • 2 glands- anterior (adenohypophysis), posterior (neurohypophysis)
  15. Adenohypoophysis
    • Location- ventral portion under hypothalamus
    • Secretions- hormones that regulate growth and secretion of other glands, tissues
  16. Growth Hormone
    Regulates growth of all body cells, promotes cell division
  17. Melanocyte Stimultaing Hormone
    Causes darkening of skin by stimulating melanin
  18. Follicle Stimulating Hormone
    • In females, it regulates monthly development of follicle and egg and secretion of estrogen
    • In males, it stimulates testes to create sperm
  19. Luteinizing Hormone
    • Works with FSH
    • Females- helps bring out ovulation, formation of progesterone
    • Males- stimulates testosterone development and secretion
  20. Thyroid Stimulating Hormone
    Regulates thyroid gland, but hypothalamus alos partially controls
  21. Adrenocorticotropic Hormone
    Promotes functioning of adrenal cortex
  22. Prolactin
    Secreted in both males and females, but functions more in females after birth- response for milk production
  23. Neuropophysis
    • Location- Dorsal
    • Is considered part of the brain- has nervous tissue
  24. Secretions- Pituitary Gland
    • ADH
    • Oxytocin
  25. Targets/Effects of Pit. Gland
    • ADH- kidney= helps to retain water, constricts blood vessels
    • Oxytocin- Uterus= contractions, delivery, breast= lactation
  26. Thyroid Gland
    • Location- in anterior neck, inferior to the larynx- just below adam's apple
    • Wraps around front of trachea, 2 lobes connected by isthmus, many BVs around it
  27. Thyroid gland secretions
    • Thyroid Hormone- Thyroxine= T4, Triiodothyronine= T3
    • Peptide hormone- contains iodine, needed for function
  28. Secretions cont'd
    Calcitonin- targets bones, retains calcium, inhibits osteoclasts
  29. Parathyroid Glands
    Location- 4 tiny glands at top and bottom of posterior surface of each lobe of the thyroid gland
  30. Parathyroid Secretion
    Parathyroid Hormone- protein hormone made by chief cells
  31. Parathyroid targets
    • Bones- increases Ca release
    • Small Intestine- increases Ca absorption
    • Kidneys- decreases Ca excretion
    • Increases Ca in bloodstream, decreases amount in bones
  32. Adrenal Cortex
    • Bulk of gland, controlled by ACTH from anterior pit.
    • Secretsover 30 hormones, called corticosteroids
    • Location= Cortex
    • Secrtes- Aldosterone=mineralocorticoid and Cortisol= glucocorticoid
  33. Adrenal Cortex Target
    • Cortisol targets, liver, muscles
    • Aldosterone targets kidney
  34. Adrenal Medulla
    • Controlled by sympathetic NS
    • Location- inside portion of gland
    • Secretion- Epi. and NE
    • Targets all sympathetic target organs
    • Effects- reinforces sympathetic mass activation, fight or flight
  35. Pineal Gland
    • Shaped like a pine cone
    • Function?
    • Location- Roof of 3rd venticle, dorsal to thalamus. dorsal/superior to midbrain(striaight back from eyes)
    • Secretes melatonin
    • Targets hypothalamus
    • Effect- helps regulate circadian rhythms, sleep
  36. Pancreas
    • Both endocrine and exocrine
    • Posterior abdominal wall, middle left side
  37. Pancreas Secretions
    • Protein hormones
    • Pancreatic islets- responsible for endocrine function (alpha, beta= cell types)
    • Glucagon- helps to release fuel into bloodstream- from alpha islets
    • Insulin- helps to store glucose/fuel- from beta islets
  38. Pancreas Targets/Effects
    Glucagon signals liver to release glucose from stored glycogen- insulin signals liver to store glucose as glycogen
  39. Thymus
    • Location- farther down trachea from thyroid, rests on top pf preicardial sac in the mediastinum
    • In front of aorta, behind sternum
  40. Thymus Secretion
    Thymic hormone- peptide hormone
  41. Thymus Target
    • Lymphoid tissues
    • Effect- increase lymphocyte production, especially T cells- help maintain imunity- gland is much larger than in children, regresses in size after puberty
  42. Gonads
    • Females- Ovaries
    • Upper pelvic cavity, one on each side of uterus, oval shaped
    • Secretes not purely endocrine gland- also produces egg cells, estrogen, progesterone
    • Targets most body tissues and growth and development, sex drive
  43. Gonads
    • Males- Testes
    • Scrotum
    • Secretes androgens
    • Produces sperm
    • Targets/effects most body tissues, growth and development, sex drive
  44. Heart
    • ANP (atrial natriuretic peptide) decreases excess blood volume, high BP, and Na concentration
    • Stimulates kidney for salt secretion
  45. GI Tract
    • Gastrin- released by stomach- stimulates HCI
    • Secretin- released by small intestine- stimulates water and bicarbonate
    • CCK- released by small intestine- stim. gallbladder, pancreatic juices
    • GIP- released by small intestine- inhibits gastric emptying, acid secretion
  46. Placenta
    Influences pregnancy
  47. Kidneys
    • Secrete erythropoietin
    • Target/Effect- red bone marrow, stimulates RBC prod.
  48. Skin
    • Precursor to vitamin D
    • Produced by modified cholesterol molecules after UV exposure
    • Signals Ca absorption from small intestine
  49. Gigantism (pituitary)
    Tumor causes hypersecretion of GH in children
  50. Acromegaly (pituitary)
    Excessive GH secretion after epiphyseal growth plates fuse
  51. Diabetes Mellitus (pancreas)
    • Insufficient insulin OR inability of cells to react to insulin
    • Blood sugar is high
    • -Type I need insulin injected
    • -Type II "adult onset" reduced insulin sensitivity
  52. Graves Disease (thyroid)
    Oversecretion of thyroid hormone (sympathetic)
  53. Hypothyroidism (thyroid)
    Hyposecretion of thyroid hormone (low metabolism)
  54. Goiter (thyroid)
    enlarged thyroid gland due to lack of iodine
Author
matt75
ID
12465
Card Set
Anatomy25
Description
25
Updated