Endocrine System Flashcards
What part of the brain links the nervous system to the endocrine system?
Via what gland?
Hypothalamus
Pituitary Gland
What happens in the thryroid follicle when stimulate by Thyroid Stimulating Hormone?
Follicular cells uptake thyroglobulin into cytoplasm to break it down into T3 & T4 to be secreted into blood
Beta cells of the Islets of Langerhans secrete what?
Insulin
What is B?
What does this layer secrete?
Zona glomerulosa secretes mineralocorticoids (aldosterone)
In repsonse to stress, ACTH stimulates Zona fasciculata to secrete its glucocorticoid (cortisol) to do what?
affect the hepatocyte, fat, skeletal muscle to maintain homeostasis by decreasing unnecessary actions
(= negative feedback loop)
What are on either side of the Hypophyseal Cavity?
pars distalis & pars intermedia
What is D?
Hypophyseal cavity
Delta cells of the Islets of Langerhans secrete what?
somatostatin
Alpha cells of the Islets of Langerhans secrete what?
glucagon
What is the retina’s role in regards to Melanin?
Retina detects stimuli, which stimulates secretion of melanin by the pinealocytes when it’s dark, siglans time of day, time of year, is an antioxidant
What does the heart secrete in regards to the endocrine system?
Atrial Natriuretic Peptide (ANP)
What is A and what does it contain?
Colloid & thyroglobulin
What is C?
Pars Distalis
What is the endocrine system?
Ductless system that secretes into blood to affect cells far away
What do the axons pass through when traveling to the andenohypophysis?
Where do the axons release the releasing hormone into?
To what part of the adenohypophysis?
What do the releasing hormones bind to to stimulate it to release its specific hormone?
- pass thru infundubulum
- portal blood supply
- pars distalis
- epithelial cell
What are the three parts of th Adenohypophysis?
Pars distalis
Pars intermedia
Pars tuberalis
What is D?
What does this layer secrete?
Zona reticularis secretes androgens
Once at the target cell, hormones bind to what?
Exception??
Recetor on cell surface
Steroids pass through plasms mem & bind to nucleus
In repsonse to low bp, angiotensin II stimulates Zona glomerulosa to secrete its mineralocorticoid (aldosterone) to do what?
increase activity of Na/K ATPase in kindey to conserve water & increase blood volume
The pyloric region of the GIT secretes what?
gastrin
What percent of the pancreas is exocrine?
98%
What percent of the pancreas is endocrine?
2%
What is B?
Pars intermedia
What are Pituicytes?
support cells for the axons
What is B?
Thyroid follicle cuboidal epithelial cell
In the hypothalamus there are cell bodies; where do the axons go through and where do they terminate?
Axons thravel through the infundibular stalk
Axons terminate on fenestrated capillaries in pars nervosa
What 2 hormones does the kidney secrete affecting the endocrine system?
Renin & Erythropoietin
What does ANP do and what does it target?
promotes Na+ & water loss to decrease bp by targeting distal convoluted tubules of the kindey
Thyroid Gland consists of what?
Follicles
What do endocrine cells produce? (general)
Hormones
What does Calcitonin do?
sense blood Ca2+ levels; when blood Ca2+ concentration is high, calcatonin is secreted to bring blood Ca2+ levels down by increasing excretion of Ca2+ in the kidney AND decreasing osteoclast activity
What are the 3 types of Basophils?
What do they secrete?
What releasing hormone from the hypothalamus is first required?
Thyroidotrophs secrete Thyroid-Stimulating Hormone and requries TRH (thyroid releasing hormone)
Gonadotrophs secrete Follicle Stimulating Hormone & Lutenizing Hormone and require GnRH (gonadotropin releasing hormone)
Corticotrophs secrete Adrenocorticotropin and require CRH (corticotropin-releasing hormone)
What does the Pineal Gland regulate?
daily rhythms of body activity