endocrine system

what are hormones?

organic chemicals produced by one set of cells that affects a different set of cells.

what do all hormones have?

a specific organ of origin, a specific target organ, a specific function.

how do hormones attach and effect cells?

through the lock and key mechanism

what are the two types of hormones?

peptide and steroid

what are peptide hormones derived from?

proteins, peptides, and catecholamines

how are peptide hormones activated?

through existing enzymes inside the cell

do peptide hormones act quickly or slowly?

quickly, and last for a short period of time

what are steroid hormones derived from?

cholesterol

what activates steroid hormones?

entering into the nucleus and altering protein synthesis

do steroid hormones react quickly or slowly?

slowly, and last for a long period of time

what are the primary Endocrine Organs in the brain?

hypothalamus, pineal gland, and anterior and posterior pituitary glands

what are the other primary Endocrine Organs that are throughout the body?

adrenal, thyroid, parathyroid, and pancreas

What are the secondary Endocrine Organs?

heart, kidneys, thymus, gonads

thymus

pancreas

adrenal glands

what is negative feedback?

an increased amount of a hormone acts to shut off the production of that hormone

what is an example of negative feedback?

ADH

how does ADH work?

it is released by the posterior pituitary gland to signal to the kidneys to retain more water, and blood is diluted.

what stops the release of ADH?

blood being diluted enough!

which is more common- negative or positive feedback?

negative feedback

what is positive feedback?

increase of the action of a hormone until the stimulus is removed

what is an example of positive feedback?

the release of oxytocin during childbirth

how is oxytocin released during childbirth?

the baby’s head pushes on the cervix, which signals the release of oxytocin.

what action does oxytocin perform during childbirth?

uterine contractions, which push the baby’s head into the cervix, triggering the release of more oxytocin.

when does oxytocin stop being released?

when the baby has been born (stimulus has been removed)

what is the main function of the hypothalamus?

to monitor homeostasis and produce hormones to be stored in the posterior pituitary

what are neurosecretory cells?

specialized neurons that can produce hormones

where are neurosecretory cells found?

hypothalamus

what is stored in the posterior pituitary?

hormones secreted by neurosecretory cells

what are the two main hormones secreted by the posterior pituitary?

Oxytocin and ADH

What is ADH’s target organ?

kindeys

What is ADH’s function?

to tell the kidneys to retain water

What is oxytocin’s target organ?

uterus

What is oxytocin’s function?

to stimulate uterine contractions during childbirth, to aid in the release of milk from mammary glands during nursing

which makes its own hormones- anterior or posterior pituitary gland?

anterior pituitary gland!

which gets its hormones from the hypothalamus- anterior or posterior pituitary?

posterior pituitary!

where is gh (growth hormone) produced?

anterior pituitary gland

what is the function of GH?

cell and bone growth, cell division, protein synthesis, increases skeletal muscle mass and stimulates liver

where is prolactin (PRL) produced?

anterior pituitary gland

what is prolactin’s main function?

development of mammary glands and production of milk, carbohydrate and fat metabolism

where is Melanocyte stimulating hormone (MSH) produced?

anterior pituitary

what is MSH’s main function?

stimulates melanocytes to increase melanin production, darkening the skin.

Where is Thyroid Stimulating Hormone (TSH) produced

anterior pituitary gland

what is TSH’s target organ?

Thyroid

what is the main function of TSH?

stimulates the thyroid gland to produce T3 and T4

where is ACTH (Adrenocorticotropic hormone) produced?

anterior pituitary gland

what is the function of ACTH?

stimulates the adrenal cortex to produce cortisol

where is FSH (follicle Stimulating Hormone) produced?

anterior pituitary

What is the function of FSH in the testes?

sperm development

What is the function of FSH in ovaries?

estrogen production and follicle maturation

where is Lutenizing Hormone produced?

anterior pituitary

what is the function of LH in testes?

testosterone development

what is the function of LH in ovaries?

ovulation (release of a mature egg cell) and release of progesterone

what is the acronym to remember all of the hormones released by the anterior pituitary gland?

FLAT GIMP- fsh, LH, ACTH, TSH, gh, MSH, prl

what do T3 and T4 require in order to be produced?

ionine

what is the function of T4?

increasing metabolic rate in all cells

what is T4 necessary for?

proper growth and development

what body changes occur when there is an underproduction- of T4 at birth?

reduced skeletal growth, sexual immaturity, abnormal protein metabolism

what is the name of the condition that occurs in people who have an underproduction of t4 at birth?

congenital hypothyroidism

what leads to goiter formation

low levels of iodine in diet, which means that thyroid cannot product t4

when the thyroid cannot product t4, what does the body do?

anterior pituitary increases the secretion of TSH, which makes the thyroid enlarge

where is calcitonin produced?

thyroid

what is the function of calcitonin

lowers the level of calcium in the blood and deposits calcium into bone

calcitonin is an antogonistic hormone to which hormone?

PTH

where is PTH produced?

parathyroid gland

what is the function of PTH?

increases level of calcium in the blood, increases calcium absorption, promotes osteocalsts

How is the production of PTH stopped?

negative feedback

what is Tetany?

when the body has low PTH production

what are symptoms of tetany?

low calcium in the blood, electrolyte balance, cramps, involuntary muscle contractions

what contributes to pituitary dwarfism

underproduction of growth hormone during childhood

what contributes to pituitary gigantism

overproduction of GH in childhood

what contributes to acromegaly

overproduction of GH as an adult

what are the two components of the adrenal glands?

adrenal medulla and adrenal cortex

what hormones does the adrenal medulla produce?

epinephrine and norepinephrine

what is epinephrine and norephinephrine’s function

to increase blood glucose level and increase metabolic rate

where are glucocorticoids produced?

adrenal cortex

what is an example of a glucocorticoid

cortisol

where are mineralocorticoids produced?

adrenal cortex

what is an example of a mineralocorticoid?

aldosterone

what is cortisol’s function?

break down muscles proteins to amino acids, amino acids to glucose, and to raise the blood glucose level

what is aldosterone’s function?

regulate levels of sodium and potassium ions in the blood

what is aldosterone’s target organ?

kidneys

where in melatonin produced?

pineal gland

what is the function of melatonin

to induce sleepiness during darkness

where is insulin produced?

pancreas

what is insulin’s function?

to lower blood glucose levels when they are high

what actions does insulin take to lower blood glucose levels?

metabolize glucose, liver stores glucose as glycogen

where is glucagon produced?

pancreas

what is glucagon’s function?

to raise blood glucose levels when they are low

where is erythtopoeietin produced?

kidneys

what is the function of erythtopoeietin?

increase the release of red blood cells from bone marrow

where is testosterone produced?

the testes

what is the function of testosterone?

development and function of sex organs in males

where is estrogen produced?

the uterus

what is the function of estrogen?

growth of the uterus and vagina, regulation of uterine cycle, egg maturation

where is progesterone produced

the ovaries

what is the function of progesterone?

breast development, maintenance of pregnancy, regulation of uterine cycle

where are thymosins produced?

thymus

what is thymosin’s function?

support the immune response, and develop t cells throughout the body