chapter 18 - the endocrine system Flashcards
what is a “free” hormone, bind to receptors in plasma membrane outside of the cell?
water soluble hormone
what is bound to transport protein, when they get to target cell they can diffuse through plasma membrane (has more direct effect)?
lipid soluble hormone
what is a mediator molecule that is released in one part of the body and has an effect on cells in another part of the body?
a hormone
what do somatotrophs release?
human growth hormone (HGH)
what does human growth hormone (HGH) do?
stimulates general body growth
what is acromegaly?
the result of excess HGH during adulthood
what are thyrotrophs release?
thyroid stimulating hormones (TSH)
what do thyroid stimulating hormones (TSH) do?
controls secretions and activities of the thyroid (T3 and T4, metabolism)
what do lactotrophs do?
secrete prolactin (PRL)
what does prolactin (PRL) do?
initiates milk production in mammary glands
what do corticotrophs do?
secrete adrenocorticotrophic hormone (ACTH)
aka: Corticotrophin
what does adrenocorticotrophic (ACTH) hormones/corticotropin do?
stimulate adrenal cortex to secrete glucocorticoids (cortisol)
what hormones do the posterior pituitary gland produce?
Antidiuretic Hormone (ADH) and oxytocin
what does ADH/vasopressin do?
decrease urine production, return more water to the blood
what do follicular cells produce?
the thyroid hormones T3 and T4
what is the hormone produced by parafollicular cells (in the thyroid)?
calcitonin
what does slow heart rate, sensitivity to cold, dry hair and skin, edema, and weight gain indicate?
hypothyroidism
what does increased heart rate, weight loss, tremors, and exophthalmus (sometimes) indicate?
hyperthyroidism
what is the most common form of hyperthyroidism?
grave’s disease
what is the most common form of hypothyroidism?
Hashimoto’s
what decreases the level of calcium in the blood?
calcitonin
what inhibits the activity of osteoclasts and bone resorption?
calcitonin
what do the parathyroid glands release?
parathyroid hormone (PTH)
what does parathyroid hormone (PTH) do?
monitors low levels of blood calcium
what do parathyroid hormones (PTH) increase?
increase the blood calcium level
what are the two parts of the adrenal glands?
the adrenal cortex and the adrenal medulla
what does the adrenal cortex produce?
steroid hormones that are essential for life
what do mineralocorticoids affect?
mineral homeostasis (aldosterone)
what do mineralocorticoids/aldosterone regulate?
sodium and potassium levels
what do mineralocorticoids maintain?
normal blood pressure and volume
what do glucocorticoids regulate?
metabolism of glucose and resistance to stress
what is the main glucocorticoid?
cortisol
what is cortisol?
the stress handling hormone of the body
what is a hyperadrenal disorder?
cushing’s syndrome
what are hypoadrenal disorders?
addison’s disease
what does glucagon do?
increases blood glucose
what happens when blood glucose increases?
hepatocytes (liver cells) convert glycogen to glucose
what does insulin do?
decrease blood glucose levels by converting glucose into glycogen
what is the loss of insulin production or the inability to respond to insulin?
diabetes mellitus
what is it called when the immune system destroys the pancreatic beta cells?
type I diabetes (congenital)
what is it called when cells in target organs become less sensitive to insulin?
type II diabetes (dietary)
