Module 5 Flashcards
What are the main functions of the endocrine system?
Regulates metabolism, growth, development, tissue function, and mood via hormones.
What is the difference between endocrine and exocrine glands?
Endocrine glands release hormones into the bloodstream (ductless), exocrine glands release non-hormonal substances through ducts.
What are the three types of stimuli that trigger hormone release?
Humoral, neural, and hormonal stimuli.
What are the two major lobes of the pituitary gland?
Anterior lobe (adenohypophysis) and posterior lobe (neurohypophysis).
What hormones are released from the posterior pituitary?
Antidiuretic hormone (ADH) and oxytocin.
What triggers ADH release and what is its function?
Triggered by low blood pressure or high plasma osmolarity; promotes water reabsorption in kidneys.
What is the role of oxytocin?
Stimulates uterine contractions during childbirth and milk ejection during breastfeeding.
What hormones are secreted by the anterior pituitary?
GH, TSH, ACTH, PRL, FSH, LH.
Which anterior pituitary hormones are tropic?
TSH, ACTH, FSH, and LH.
Which hormone has both tropic and non-tropic effects?
Growth hormone (GH).
How is growth hormone regulated?
By GHRH (stimulates) and GHIH (inhibits) from the hypothalamus.
What is the effect of hypersecretion of GH before puberty?
Gigantism.
What is the effect of hypersecretion of GH after puberty?
Acromegaly.
What does TSH do?
Stimulates the thyroid gland to release thyroid hormones (T3 and T4).
What are the symptoms of hypothyroidism?
Weight gain, fatigue, cold intolerance, constipation, and slow reflexes.
What condition is caused by hypothyroidism in children?
Cretinism.
What are the effects of thyroid hormone?
Increases metabolic rate, heart rate, and supports growth and development.
What is the role of prolactin?
Stimulates milk production; regulated mainly by dopamine (PIH).
Which hormone regulates the adrenal cortex and what does it do?
ACTH; stimulates cortisol release for stress response.
What is the primary hormone involved in the body’s response to stress?
Cortisol, released from the adrenal cortex via stimulation by ACTH.
What is the difference in communication between the hypothalamus and the anterior vs posterior pituitary?
Anterior pituitary is controlled by hormones via the portal system; posterior pituitary via neural signals through the hypothalamic-hypophyseal tract.
What are the two hormones stored in the posterior pituitary and where are they produced?
Oxytocin and ADH, produced in the hypothalamus.
What is the function of the hypothalamic-hypophyseal portal system?
Delivers hypothalamic hormones directly to the anterior pituitary without dilution in systemic circulation.
Which hormone increases during dehydration and why?
ADH increases to promote water reabsorption and conserve body fluids.
