Question | Answer |
What glands are included in the endocrine system? | pituitary, thyroid, parathyroids, adrenals, pancreas, gonads(ovaries and testes). Pineal gland, thymus, secretory cells of the GI tract |
Main function of the endocrine system | regulation and integration of body processes. Maintains a controlled environment |
3 General characteristics of endocrine glands | 1) secretion of hormones, 2)ductless glands, 3)well vascularized |
hormones | chemical messengers ("regulators") which affect the activity of other cells |
ductless glands | secrete products directly into blood stream |
What is the most efficient way to distribute things systemically that is utilized by the endocrine system? | secrete directly into the blood stream |
Describe the blood supply of endocrine glands | well vascularized |
A certain endocrine gland affects it's ... | target tissue |
What is the general effect of endocrine glands? | slow but long lasting. Opposite of CNS and PNS |
negative feedback mechanism and example | low levels increase production, when levels are high again it forces secretion to stop. Ex. Insulin |
What neural structure is involved in endocrine control? | hypothalamus. |
Releasing factors | Secreted by the hypothalamus. Stimulate glands to secrete their specific hormones. |
Example of a releasing factor | GHRF. Growth hormone releasing factor. Causes pituitary to release growth hormones. Secreted by the hypothalamus |
What is another name for the pituitary? | hypophysis |
What is the "master gland" and why | pituitary gland. It regulates many body activities through its action on other endocrine glands |
Location of the Pituitary | Inferior surface of brain. Beneath the hypothalamus. Surrounded by the Circle of Willis. |
What are the 2 lobes of the pituitary? | adenohypophysis and neurohypophysis |
adenohypophysis | Anterior pituitary. Glandular portion. Produces and secretes 6 major hormones. |
neurohypophysis | Posterior lobe. Nervous portion. Stores and releases 2 hormones produced by the hypothalamus. DOES NOT PRODUCE HORMONES. |
Does the neurohypophysis produce hormones? | NO! |
What are the 6 hormones secreted by the anterior pituitary? | Growth Hormone (GH), Thyroid stimulating hormone (TSH), Adrenocorticotropic hormone (ACTH), Follicle stimulating hormone (FSH), Luteinizing hormone (LH), prolactin |
Growth Horomone (GH) | ANTERIOR PITUITARY.Increases protein synthesis and mitosis. Regulates growth of most cells in the body. |
Thyroid-stimulating hormone (TSH) | ANTERIOR PITUITARY.Regulates the hormonal activity of the thyroid gland. |
Adrenocorticotropic hormone (ACTH) | ANTERIOR PITUITARY.controls secretion of hormones in the adrenal cortex |
Follicle-stimulating hormone (FSH) | ANTERIOR PITUITARY. Stimulates follicle (ova) development in ovaries and sperm development in testes. Stimulates sex hormone secretion. |
Luteinizing hormone (LH) | ANTERIOR PITUITARY. Plays a role in ovulation. Stimulates secretion of sex hormones (estrogen and testosterone) |
Prolactin | ANTERIOR PITUITARY. plays a role in the secretion of milk from the mammary glands. ("Lactation") |
Oxytocin | POSTERIOR PITUITARY STORES AND SECRETES. Stimulate uterine contractions (delivery). Promotes milk ejection from breasts. (we can induce labor with drug that is similar) |
Antidiuretic hormone (ADH) | POSTERIOR PITUITARY STORES AND SECRETES. Affects permeability of the kidney tubules to reduce excretion of water. (#vasopressin, controls blood pressure, constrict blood vessels) |
What are the 2 hormones produced by the hypothalamus that are stored and secreted by the posterior pituitary? | Oxytocin and antidiuretic hormone |
What are the 3 Hormones produced by the thyroid gland? | thyroxine(T4), Triiodothyromine (T3), and calcitonin |
Location of the Thyroid Gland | Inferior to larynx, surround anterior and lateral aspect of trachea. Anterior neck. |
Gross Structure of the Thyroid Gland | 2 lobes connected by isthmus. May contain a pyramidal lobe (superior extension) |
Microscopic structure of the thyroid gland | contains cuboidal cells - hormone production. Follicles store hormones. |
Thyroxine (T4) | THYROID.Found in most cells. Regulates basal metabolic rate (BMR).Like T3 |
Triiodothyromine (T3) | THYROID.Found in most cells. Regulates basal metabolic rate (BMR). Like T4 |
Calcitonin | THYROID. Site of Action: Bone. EFFECT: regulates osteoclast activity(breakdown of bone). Regulates amt of Ca that leaves Bone. Lowers Calcium blood Levels. |
What hormone does the parathyroid gland produce? | Parathyroid hormone (PTH) |
Location of parathyroid gland | embedded on posterior side of thyroid. (4) |
Parathyroid Hormone (PTH) | PARATHYROID. Site of Action:osteoclast in bone, kidneys, intestines. Effect: Increase blood calcium levels. Opposite of calcitonin |
What does basal metabolic rate effect? | Weight gain, body temp, energy |
What are the Hormones produced by the adrenal glands? | Epipnephrine, Aldosterone, Cortisol, Androgens |
Location of adrenal glands | "suprarenal" Paired glands located on superior pole of kidneys |
Medulla of adrenal glands | inner portion. Activated by stress. "Flight or Fight" response. |
Cortex of adrenal glands | outer portion. produces cortico-hormones. Responds to ACTH stimulation. |
epipnephrine | ADRENAL.(catecholamines) Reinforces and prolongs sympathetic ANS response. Circulates to various organs and tissues through blood |
Aldosterone | ADRENAL. "mineralcorticoid". Site of action: Kidney tubules. Regulates Na and K levels |
Cortisol | ADRENAL "glucocorticoid" (hydrocortisone). Regulates metabolism(glucose). Prevent/reduce inflammation. Acts on various tissues. (Side effect:reduce immune response, weight gain) |
Androgens | ADRENAL. (estrogen, progesterone). Supplement gonadal hormones. Promote development of secondary sex characteristics. Various sites of action. |
Location of pancreas | posterior/inferior to stomach. Upper abdomen. |
Structure of pancreas | exocrine (duct travel) and endocrine(blood stream travel) portions. |
general hormones of the exocrine portion of pancreas | contains cells and ducts, Digestive enzymes that are released into the duodenum of the small intestine. |
Beta cells | ENDOCRINE PANCREAS. Act On:All body Cells. Regulates transport of glucose into cells |
Alpha cells | ENDOCRINE PANCREAS. Act on: Liver. Produces glucagon to break down glycogen into glucose. |
Pineal gland location | suspended from roof of third ventricle |
Melatonin | PINEAL GLAND. receives and responds to input from the visual pathway. Is at highest level at night. May effect wake/sleep cycle. Inhibits hypothalamus stimulation of hormones which stimulate the glands. delays sexual maturation. |