Endocrine System Flashcards
What’s is the relationship between the hypothalamus and the posterior pituitary?
The relationship is it is part of the central endocrine organs(located in brain).
The hypothalamus produces 9 hormones & controls pituitary. Endocrine is mostly controlled by hypothalamus & pituitary.
What is the portal system and how does it facilitate hormone action by the hypothalamus?
Portal system: filtration system w/ capillary beds.(liver & kidneys)
Hypothalamus capillary bed -> anterior pituitary capillary bed. Facilitates by preventing dilution in general circulation and filtering by L/K. Faster and stronger effect.
How is your body able to use the hypothalamus and osmoreceptors to monitor dehydration?
During dehydration -> increase blood osmolarity -> stimulates osmoreceptors -> synapse w/ hypothalamus -> release ADH.
Osmoreceptors and dehydration
Osmoreceptors: decrease in plasma volume -> increase solutes -> osmotic pressure -> water out of cell -> cell shrinks -> mechanoreceptor stimulated.
ETOH inhibits release of ADH!
How is oxytocin release regulated?
The hypothalamus sends impulses to the posterior pituitary to release oxytocin into the blood stream.
Oxytocin also triggers uterine contractions, which push against the cervix to send a higher frequency of impulses. Greater pressure on the cervix triggers more oxytocin release until fetus is delivered.
What is a tropic hormone?
A hormone that stimulates another endocrine gland to secrete a hormone.
How are Hashimoto disease and Graves’ disease similar and different?
Similarities: Both are autoimmune diseases.
Differences: Hashimoto is is Hypothyroidism and Graves is Hyperthyroidism.
Hashimoto Disease
Antibodies are made against thyroglobulin or iodinating enzyme (thyroid peroxidase)
Graves Disease
The body makes antibodies that bind to TSH receptors on the thyroid which can lead to protruding eyes.
Why isn’t Graves’ disease subject negative feedback inhibition?
There is an over production of thyroid hormone, which lead to thyroid enlargement. Also triggers some response as TSH. Thyroid hormone does not inhibit antibodies that bind to TSH receptors.
What is the cause of goiter? How is the thyroid gland impacted? Why does iodine deficiency disrupt thyroid hormone negative feedback inhibition in goiter and how is goiter treated?
Inadequate iodine in the diet.
The thyroid gland will enlarge.
The thyroid gland has an inactive thyroid hormone being made, but is not recognized. (No-feedback)
What is the role of Melatonin?
Helps keep the body’s circadian rhythms in synchrony with light/dark cycles.
Promotes sleep, released cyclically for sleep. Secreted by pineal gland in brain.
Promotes onset of puberty.
Enhances immunity.
What is the role of calcitonin?
Lowes blood Ca 2+
Inhibits osteoclasts from releasing Ca2+ and stimulates Ca2+ excretion by the kidneys.
What is the role of parathyroid hormone?
Secretes PTH (Parathyroid Hormone)
What two hormones made by the pancreas work opposite of each other to maintain a blood glucose level of 90-100 mg/dL and in which cell type is each hormone made?
Endocrine and Exocrine.
Insulin: secreted by pancreatic B cell in response to increase blood glucose.
Glucagon: secreted by a cell in response to decrease in blood glucose.
