Chapter 13 Flashcards
This system is composed of organs and endocrine glands that release their hormones directly into the blood steam
the endocrine system
a chemical that is secreted or made by an endocrine gland
hormone
each hormone only affects what? This cell has receptors for that hormone.
target cell
when does the hormone begin its effect
once the hormone binds to or enters its target cell
why do we need regulation of hormones?
to prevent over or under production of a hormone, because there are side effects of either one
what are the three ways that hormones are regulated?
1 - via input signals from the nervous system: epinephrine or norepinephrine
2 - chemical changes in the blood: parathyroid hormone responds to levels of calcium in the blood
3 - other hormones cause changes: ACTH regulates cortisol
what are the 10 endocrine glands from head moving down the body
hypothalamus pineal gland pituitary gland - anterior and posterior thyroid gland parathyroid glands thymus gland adrenal glands pancreas ovaries testes
this organ of the brain contains neurons that secrete hormones; it works very closely with the posterior pituitary in that hormones that are made in this organ are stored and secreted by the posterior pituitary
hypothalamus
how does the hypothalamus control the anterior pituitary
it either activates or inhibits secretion of hormones from the anterior pituitary
known as the regulatory system for homeostasis
hypothalamus
what two hormones does the hypothalamus produce and store in the posterior pituitary; posterior pituitary secretes them
ADH - antidiuretic hormone
OT - Oxytocin
This hormones function is to conserve water by decreasing urine output and is secreted by the posterior pituitary
ADH - Antidiuretic hormone
describe how ADH works in the system 6 steps
1 - workout occurs
2 - sweating happens which decreases blood volume
3 - hypothalamus is stimulated, and so it stimulates the posterior pituitary
4 - ADH is secreted
5 - ADH acts on the kidneys; kidneys reabsorb more water into the plasma
6 - blood volume increases
This hormones function contracts the uterus during labor and stimulates release of milk or milk ejection during nursing; it is produced by the hypothalamus but secreted by the posterior pituitary
Oxytocin
what is the name of the synthetic oxytocin that is used for inducing labor
Pitocin
Describe the process of oxytocin in the body during labor
1 - the head of the baby stretches the cervix of the mothers uterus.
2 - in response to the stretching, nerve impulses are sent to the hypothalamus
3 - the hypothalamus signals the posterior pituitary to release oxytocin
4 - the posterior pituitary release Oxytocin, which travels n the blood to muscles of the uterus
5 - the uterus responds to Oxytocin by contracting more vigorously
6 - Uterine contractions increase dilation of the cervix, which stimulates further release of Oxytocin, which stimulates even more frequent and vigorous contractions
7 - At birth, stretching of the cervix lessens and the positive feedback cycle is broken
Tis gland is the size of a pea, with 2 lobes anterior and posterior and is connected to the hypothalamus through the infundibulum
pituitary gland
There are 7 major hormones that the anterior pituitary gland secretes what are the six you are required to know
1 - LH - luteinizing hormone 2 - FSH - follicle stimulating hormone 3 - hGH - human growth hormone 4 - PRL - Prolactin 5 - ACTH - adrenocorticotropic hormone 6 - TSH - Thyroid stimulating hormone
The function of this hormone is to stimulate growth of tissue and is usually only secreted during childhood
hGH - Human growth hormone
This condition is caused by too much hGH being secreted during childhood; usually caused by tumors on the pituitary
Gigantism
This condition is caused by having abnormally high amounts of growth hormone when you are adult and is usually caused by a tumor on the pituitary, it causes significant thickening of your hand, feet and jaw
Acromegaly
This condition is under production of the human growth hormone in childhood usually caused by a tumor on the pituitary, people with this condition are usually shorter than 4 feet tall and they can be treated with hGH medication to counteract the condition but those meds need to be given during childhood
Pituitary dwarfism
This hormones function is to stimulates milk production during nursing
prolactin
Prolactin is also produced by men for some unknown reason but overproduction of prolactin can cause what
erectile dysfunction