Endocrine System Flashcards
What is the endocrine systems primary means of travel?
the blood
How does the endocrine system regulate other organ systems?
by maintaining homeostasis
What type of response system is the endocrine system?
slow response system
what are the two liquid tissues of the body?
blood and cerebrospinal fluid
what two systems does blood link?
endocrine and cardiovascular system
What other system does the endocrine system work with?
nervous system
How do the endocrine and nervous system differ?
The endocrine system brings about its effects via the secretion of hormones into the blood stream and the nervous system uses action potentials and release neurotransmitters
hormones
middle managers
endocrine glands
bosses
other cells
workers
What endocrine glands secrete hormones as their primary function?
hypothalamus, pituitary glands, pineal glands, thyroid glands, parathyroid glands, thymus, adrenal glands, pancreas, ovaries, testes
What organs secrete hormones as their secondary function?
heart, adipose tissues, kidneys, and the stomach
what is known as the neuroendocrine organ?
the hypothalamus
what can the hypothalamus be likened to?
endocrine system chief executor
The hypothalamus works close with?
the pituitary gland
What is the pituitary gland attached to?
infundibulum
What are the two seperate structures of the pituitary gland?
anterior pituitary gland (adenohypophysis) and posterior pituitary gland (neurohypophysis)
What are the posterior pituitary/neuropypophysis composed of?
nervous tissue instead of glandular tissue
What two types of hormones does the hypothalamus produce?
inhibiting and releasing hormones
What do the hormones the hypothalamus produce stimulate?
secretion from the anterior pituitary gland
How does the hypothalamus communicate with the anterior pituitary gland?
hypothalamic-hypophyseal portal system
What does oxytocin do?
triggers uterine contraction and milk ejection from the mammary gland
What does antidiuretic hormone do?
causes water retention from the kidneys
What type of hormones does the anterior pituitary gland mostly produce?
tropic hormones
Examples of tropic hormones (anterior pituitary/adenohypophysis)
Thyroid stimulating hormone, prolactin, adrenocorticotropic hormone, luteinizing hormone and follicle stimulating hormone
What does thyroid stimulating hormone (TSH) do?
stimulates growth of and secretion from the thyroid
what does prolactin do?
stimulates milk production from mammary glands
What does adrenocorticotropic hormone (ACTH) do?
stimulates secretion from the adrenal cortex
What are the two reproductive hormones?
luteinizing hormone and follicle stimulating hormone which primarily affect the testes and ovaries
What does growth hormone do?
increases rate of cell division and protein synthesis in all tissues and has both tropic and nontropic affects
What does the posterior pituitary gland store?
ADH and oxytocin
What does the pineal gland secrete?
melatonin
What is the thin band called that connects the right and left lobes of the thyroid gland?
isthmus
What is the isthmus composed of?
hollow spheres called thyroid follicles
What are the cells called that line the thyroid follicles?
follicle cells
what do follicle cells suround?
colloid
T3
triiodothyronine
T4
thyroxine
What is located between follicles and what does it produce?
parafollicualr cells that produce calcitonin
What does calcitonin do?
plays a role in calcium ion homeostasis
What does parathyroid hormone do?
main hormone in the body that maintains calcium ion homeostasis
What is the difference between calcitonin and parathyroid hormone?
Calcitonin is secreted when calcium ion levels in the blood rise; parathyroid hormone is secreted when there is a decreased level of calcium ions in the blood
What do thymosin and thymopoietin do?
stimulate the development of T lymphocytes
What two seperate structures make up the adrenal gland?
Adrenal cortex and adrenal medulla
What type of hormones does the adrenal cortex produce?
steroid hormones
What does the zona glomerulosa secrete?
mineralocorticoids
What does aldosterone do?
regulate fluid, electrolyte, and acid-base homeostasis
What does the zona fasciculata secrete?
glucocorticoids
What does cortisol (glucocorticoids) do?
regulates the stress response, blood glucose, fluid homeostasis and inflammation
What does the adrenal medulla secrete?
epinephrine and norepinephrine (catecholamines)
What carries out the pancreas’s exocrine functions?
pancreatic acini
What carries out the pancreas’s endocrine functions?
pancreatic islets
What do the pancreatic islets secrete?
insulin and glucagon
what produces insulin?
beta cells of pancreas
What does insulin do?
lowers blood glucose levels
What produces glucagon?
alpha cells of pancreas
What does glucagon do?
raises blood glucose levels
What produces testosterone?
The interstitial cells of the testes
What does testosterone do?
promotes the production of sperm and the development of msle secondary sex characteristics (deeper voice, greater bone, muscle mass, and facial hair)
What does estrogen do?
plays a role in the development of oocytes (female gametes) and female secondary sex characteristics (breasts and subcutaneous fat stores)
What does progesterone do?
number of effects that prepares the body for pregnancy
Characteristics of the nervous system functions
directly effect target cells, immediate but short in duration
Characteristics of endocrine system functions
act on distant targets, not immediate, longer lasting
How do hormones regulate the process of other cells?
production of enzymes or other hormones, changing the metabolic rate of a cell, altering permeability of the plasma membrane
Where is the hypothalamus located?
inferior part of diencephalon
What is the anterior pituitary gland composed of?
glandular epithelium
Explain how the hypothalamic hypophyseal portal system works
releasing and inhibiting hormones are synthesized by hypothalamic neurons after they travel through small veins in the infundibulum, enter a second capillary bed in anterior pituitary where they exit the blood and interact with anterior pituitary cells to influence their functions
What hormones does the hypothalamus make?
made in hypothalamic neurons, oxytocin and antidiuretic hormone
Characteristics of colloid
gelatinous, iodine rich
What does the thryoid produce?
thyroxine, triiodothyronine
Antagonist hormones
calcitonin and PTH
insulin and glucagon
Examples of mineralcorticoids
aldosterone
example of glucocorticoids
cortisol
What does the zona reticularis secrete?
gonadocorticoids