Chapter 14 Flashcards
(157 cards)
endocrine system
produces hormones that directly enter the bloodstream to travel to specific tissues or organs as well as maintains homeostasis
ductless glands of the endocrine system
1) pituitary
2) thyroid
3) parathyroid
4) adrenal
5) pancreatic
6) pineal
7) thymus glands
8) ovaries
9) testes
functions of hormones
regulate:
- growth
- metabolism
- reproduction
- energy level
- sexual characteristics
antagonistic
acting in opposition; mutually opposing
electrolytes
salts and minerals that conduct electrical impulses in the body
glucagon (target organ and function)
target liver and blood by raising blood fluid level by accelerating conversion of glycogen into glucose in the liver and other nutrients into glucose in the liver and releasing glucose into blood
glucagon (disorders)
a deficiency in glucagon may cause persistently low blood glucose levels (hypoglycemia)
glucose
simple sugar that is the end product of carbohydrate digestion
sympathomimetic
agent that mimics the effects of the sympathetic nervous system, the division of the nervous system that increases the “fight or flight” response
pituitary gland (hypophysis)
a pea-sized organ located at the base of the brain which regulates many body activities and stimulates other glands to secrete their own specific hormone; consists of two portions:
1) adenohypophysis
2) neurohypophysis
adenohypophysis
the anterior lobe of the pituitary gland which is triggered by the action of the hypothalamus and produces at least six hormones
neurohypophysis
the posteriori lobe of the pituitary gland which stores and secretes two hormones produced by the hypothalamus:
1) antidiuretic hormone
2) oxytocin
thyroid gland
the largest gland of the endocrine system (H-shaped) located in the neck just below the larynx; composed of two large lobes that are separated the isthmus; produces thyroid hormone
thyroid hormone
the body’s major metabolic hormone; increases the rate of oxygen consumption, including the rate at which carbohydrates, proteins, and fats are metabolized; is actually two active iodine-containing hormones:
1) thyroxine
2) triiodothyronine
calcitonin (target organs and functions)
- regulated calcium levels in the blood in conjunction with parathyroid hormone
- decreases the reabsorption of calcium and phosphate from bones to blood
calcitonin (disorders)
most significant effects are excerpted in childhood when bones are growing and changing dramatically in mass, size, and shape
thyroxine (T4) and triiodothyronine (T3) (target organs and functions)
- increases energy production from all food types
- increases rate of protein synthesis
thyroxine (T4) and triiodothyronine (T3) (disorders)
- hyposecretion in infants caused cretinism; in adults it causes myxedema
- hypersecretion caused Graves disease, which results in exophthalmos
parathyroid glands
at least four separate glands located on the posterior surface of the lobes of the thyroid gland; secretes parathyroid hormone
parathyroid hormone (PTH) (target organs and functions)
bones: increases the reabsorption of calcium and phosphate from bone to blood
kidneys: increases calcium absorption and phosphate excretion
small intestine: increases absorption of calcium and phosphate
parathyroid hormone (PTH) (disorders)
- hyposecretion causes tetany
- hypersecretion causes osteitis fibrosa cystica
adrenal glands (suprarenal glands)
paired organs covering the superior surface of the kidneys that are divided into two sections:
1) adrenal cortex
2) adrenal medulla
adrenal cortex
makes up the bulk of the adrenal gland and produce three types of steroid hormones:
1) mineralocorticoids
2) glucocorticoids
3) sex hormones
mineralocorticoids (target organs and functions)
MAINLY ALDOSTERONE; kidneys: increase blood levels of sodium and decreases blood levels of potassium in the kidneys