Endocrine system Flashcards
What is a hormone?
A long distance chemical signal
How would chemical/hormones be transported throughout the body?
Via blood or lymph
What is endocrinology?
The study of hormones and endocrine glands?
What are the major organs called in the endocrine system?
- Pituitary
- Thyroid
- Parathyroid
- Adrenal
- Pineal
What do the endocrine glands produce?
Hormones
What do the exocrine glands produce?
Nonhormonal substances (sweat, saliva)
Where do endocrine glands secrete their production?
Surrounding tissues
What does the plasma membrane not allow the passage of?
Amino acids
What does the plasma membrane allow the passage of?
Steroid hormones (lipids)
Does the posterior pituitary lobe produce or store hormones?
Store hormones
What is the major function of ADH?
regulates water balance & inhibits urine formation
What is the major function of oxytocin?
released during childbirth, stimulant of uterine contraction
What does the ADH target?
kidney tubules
What kind of tissue is the anterior pituitary lobe associated with?
Glandular tisse
How is communication done between the anterior pituitary lobe and the hypothalamus?
Hypothalamus —> Hypophyseal portal veins —> Anterior Posterior Lobe
How many hormones are produced/released by the anterior pituitary lobe?
six
What are the six hormones produced by the anterior pituitary lobe?
-TSH
-GH
-FSH
-LH
-ACTH
-PRL
All anterior pituitary lobes are?
Proteins
What is a tropic hormone?
regulates secretory actions of endocrine glands
What are the direct action of GH hormones?
metabolism: increases blood levels of fatty acids; protein synthesis; conserves glucose
What does the hypersecretion of GH result in?
gigantism (children)
acromegaly (adults)
What does hyposecretion GH result in?
pituitary dwarfism
What do the terms hypo/hypersecretion mean?
Not enough or too much hormone production
What is TSH released by?
Anterior pituitary lobe
What is the process from the hypothalamus to TSH being released?
Hypothalamus (TRH) —> Anterior Pituitary Lobe (TSH) —> Thyroid (TH) —> target cells
What is the thyroid composed of?
isthmus: two lateral lobes
What do follicular cells produce?
Thyroglobulin
What do thyroglobulin produce?
Colloid
What hormone does the parafollicular cell produce?
calcitonin
What is the goal of TH?
regulate tissue growth and development & increase metabolic rate and heat production
What is required of thyroglobulin?
follicular cells
What are some homeostatic imbalances of the hyposecretion of TH?
myxedema (goiter)
cretinism
What is its lack of in TH hyposecretion?
iodine
What HI results in infants concerning hyposecretion of TH?
Cretinism
What is the most important hormone for calcium ion regulation?
PTH
What is PTH? What is it produced by?
Parathyroid hormone ; parathyroid gland
Kidney tubules target what activation?
Vitamin D
What is the antagonist to PTH?
calcitonin
Which part of the adrenal gland helps with acute stress?
Adrenal medulla
What kind of tissue is in the adrenal medulla?
nervous tissue
What is ACTH?
Adrenocorticotropic hormone
What is ACTH target organs?
Adrenal glands
What are the two major parts of the adrenal gland?
Adrenal medulla and adrenal cortex
What are targeted to maintain calcium regulation?
Osteocytes
Low blood calcium stimulate what to be produced?
PTH released.
What kind of tissue is the adrenal medulla?
nervous tissue
Which part of the adrenal gland helps with chronic stress?
Adrenal cortex
What does the adrenal cortex produce?
corticosteroids
What are the three major regions of the adrenal cortex
Zona glomerulosa, retiuclaris, fasciculata
What is the most common hormone by mineralcorticoids?
Aldosterone
What does aldosterone do?
Stimulates water reabsorption and water retention
What do glucocorticoids produce?
cortisol (hydrocortisone)
What do aldosterone and cortisol respond to? What part of the adrenal gland do they respond to?
ACTH and adrenal cortex
What leads to Cushing’s syndrome/disease?
Glucocorticoid imbalance (over production)
What is a symptom of Cushing’s syndrome/disease?
High blood glucose and blood pressure
What leads to Addison’s disease?
lower production of glucocorticoids and a mineralocorticoid deficiency
What are the symptoms of Addison’s disease?
Hypotension, weight loss, and sever dehydration
What are gonadocorticoids?
sex hormones
What cells produce epinephrine and norepinephrine
medullary chromaffin cells
What are the medullary chromaffin cell effects?
fight or flight, vasoconstriction, high heart rate, high blood sugar, blood diverts to brain, heart, and skeletal muscles
What are the hormones from gonadotropins?
FSH & LH
What does LH target?
The ovaries and testes
What does FSH target?
Stimulates estrogen and sperm production
What is the temporary organ of the body?
placenta
What does prolactin (PRL) stimulate?
milk production
Is PRL a +/- feedback?
+ feedback
Where is the pineal gland located?
hangs from the third ventricle (brain)
What produces melatonin?
pinealocytes
What is responsible for normal development of T cells?
thymus
What does the pancreas produce?
insulin and glucagon
Which cell produces glucagon?
Alpha cell
Which cell produces insulin
Beta cell
What does insulin do?
lowers blood sugar
What is glucagon’s target?
the liver
What is a humoral stimulus?
hormone release caused by altered levels of certain critical ions or nutrients
What is neural stimulus?
hormone release caused by neural input
What is hormonal stimulus?
hormone release caused by another hormone ( a tropic hormone)
