Endocrine system Flashcards
Endocrine system
A biochemical communication network through which several small glands control a broad range of vital body activities
Endocrine glands
Secrete hormones
Are chemical messengers that may affect a single organ or the entire body
Major endocrine glands
Pituitary
Adrenal
Thyroid
Parathyroid glands
Adrenal glands
The adrenal medulla secretes fight or flight hormones-epinephrine
Pituitary glands
“Master gland” is a tiny gland that is suspended from the base of the brain by a slender stalk
Sits in the sella turcica
Hypothalamus
Controls pituitary hormone secretions
Anterior lobe of the pituitary
Secretes growth hormone, thyroid-stimulating hormone
Posterior lobe of the pituitary
Produces vasopressin (ADH) and oxytocin
Hyperpituitarism
Caused by excessive growth hormone
Results in acromegaly in adults and gigantism in children
Hypopituitarism
Causes profound generalized disturbances in bone growth and maturation
In children, it results in a type of dwarfism
Diabetes insipidus
Not related to diabetes Mellitus
Kidneys do not conserve water
Low ADH levels
Can occur when the kidneys fail to respond to circulating ADH
Thyroid gland
Butterfly shaped gland in the neck at the level of the larynx.
Has two lobes, one on each side of the trachea
Secretes thyroxine, stimulates cellular metabolism in response to the body’s need for increased energy production
Thyroid nodules
Masses that may be hyperfunctioning or poor functioning. Nuc med
Hyperfunctioning nodules are “hot”
Poor functioning nodules are “cold”
Hyperthyroidism
Excessive thyroid hormone production. Happens more in women
Termed Graves’ disease, the entire gland is affected
Hypothyroidism
Diminished thyroid hormone production
Can result from any structural or functional abnormality
