The Endocrine System Flashcards
Hormones are chemical messengers transported by the _____
bloodstream
_____ glands have ducts and have extracellular effects as in food digestion. _____ glands have no ducts and have intracellular effects such as altering target cell metabolism.
exocrine, endocrine
several chemical function as both _____ and _____ such as norepinephrine, cholecystokinin, thyrotropin-releasing hormone, dopamine and antidiuretic hormone. Endocrine and nervous systems regulate each other. Neurons trigger _____ secretion, and _____ stimulate or inhibit neurons.
hormones, neurotransmitters, hormone, hormones
3 chemical classes of hormones
steroids
peptides and glycoproteins
monoamines
_____ are derived from cholesterol. They are secreted by _____ and _____ glands. They include estrogens, progesterone, testosterone, cortisol, corticosterone, aldosterone, DHEA, and calcitriol
steroids, gonads, adrenal
Peptides and glycoproteins are created from _____ _____ and secreted by the _____ and _____. They include oxytocin, antidiuretic hormone, releasing and inhibiting homrones, and anterior pituitary hormones.
amino acids, pituitary, hypothalamus
_____ are derived from amino acids and secreted by _____, _____ and _____ glands. They include epinephrine, norepinephrine, melatonin, and thyroid hormone
monoamines, adrenal, pineal, thyroid
The hypothalamus “instructs” the pituitary gland by producing _____ factors or _____ factors which affect pituitary function.
releasing, inhibiting
Thryotropin Releasing Hormone (TRH), Corticotroping Releasing Hormone (CRH), Gonadotropin Releasing Hormone (GnRH), and Growth Hormone Releasing Hormone (GHRH) are all hormones that stimulate or inhibit the _____ pituitary
anterior
The _____ form the floor and wall of the third ventricle of the brain and is made of neurological tissue (not glandular tissue). It regulates primitive functions of the body from including water balance, thermoregulation, sex drive, and childbirth.
hypothalamus
The _____ gland (_____) is suspended from the hypothalamus by a stalk called the _____. It is housed in a depression of the sphenoid bone called the _____ _____. It has the size and shape of a kidney bean.
pituitary, hypophysis, infundibulum, sella turcica
The _____ pituitary (adenohypophysis) is made of _____ tissue, and the _____ pituitary (neurohypophysis) is made up of _____ tissue.
anterior, glandular, posterior, neural
Hypothalamic releasing and inhibiting hormones travel in the _____ _____ system from the hypothalamus to the anterior pituitary.
hypophyseal portal
Oxytocin (OT) and antidiuretic hormone (ADH) influence the _____ pituitary.
posterior
Oxytocin and antidiuretic hormone are both _____ and _____ by the posterior pituitary, but it does not _____ them.
stored, released, synthesize
_____ increases water retention, thus reducing urine volume and preventing dehydration. It is also called vasopressin because it can cause _____.
ADH, vasoconstriction
_____ stimulates labor contractions during childbirth. It also stimulates the flow of milk during lactation.
Oxytocin
The 2 gonadotropinc hormones that target the gonads
FSH (follicle stimulating hormone)
LH (luteinizing hormone)
FSH stimulates the secretion of _____ sex hormones, the development of ovarian _____, and _____ production
ovarian, follicles, sperm
LH stimulates _____, stimulates the corpus luteum to secrete _____, and stimulates the testes to secrete _____
ovulation, progesterone, testosterone
_____ stimulates the secretion of thyroid hormone
thyroid stimulating hormone (TSH)
_____ stimulates the adrenal cortex to secrete glucocorticoids.
adrenocorticotropic hormone (ACTH)
After birth, _____ stimulates the mammary glands to synthesize milk. It also enhances the secretion of testosterone by the testes.
prolacting (PRL)
_____ stimulates mitosis and cellular differentiation.
growth hormone (GH)
Control of the pituitary through feedback from target organs: _____ feedback increases target organ hormone levels to inhibit the release of hormones from the pituitary. In _____ feedback, the stretching of the uterus increases OT release, causing mores stretching of the uterus until delivery occurs.
negative, positive
_____ stimulates adenohypophysis of the anterior pituitary. _____ has widespread effects on the body tissues, especially the cartilage, bone, muscle and fat. It induces the _____ to produce growth stimulants including insulin-like growth factors (IGF-I) or somatomedins (IGF-II). They increase _____ synthesis and _____ metabolism.
Growth Hormone Releasing Factor (GHRF), liver, protein, lipid
Hypersecretion of GH in adulthood can lead to _____. It is usually due to _____ in the pituitary gland. It can alter the facial bones, enlarges the hands and feet, increase bone density, and increase sweating.
acromelagy, adenoma
Hypersecretion of growth hormone in children is rare, and is usually due to _____ of the pituitary. It can result in _____.
adenoma, giantism
The _____ _____ is our biological clock and is stimulated by light. It may synchronize our physiological function with a 24-hr circadian rhythm of daylight and darkness. It synthesizes _____ from serotonin during the night, and this process fluctuates seasonally with changes in day length.
pineal gland, melatonin
_____ _____ disorder occurs in the winter or northern climates. Its symptoms are depression, sleepiness, irritability and carbohydrate craving. _____ involves 2-3 hours of exposure to bright light each day reduces the _____ levels and the symptoms.
seasonal affective disorder (SAD), phototherapy, melatonin
The thymus plays a role in these 3 systems
endocrine
lymphatic
immune
The _____ is the bilobed gland in the mediastinum superior to the heart. It progressively degenerates or shrinks after _____. It is the site of maturation of _____, which are important in immune defense. It also secretes hormones that stimulate the development of other lymphatic organs, as well as the activity of T-lymphocytes.
thymus, puberty, T-cells
The thyroid gland secretes _____ which has ___ iodine atoms, and _____ which has ___ iodine atoms. _____ is converted into _____.
thyroxine (T4), 4, triiodothyronine (T3), 3, T4, T3
The _____ is considered the “master gland.” Thus, dietary _____ is necessary,
–too little can cause _____, but this is rare in the US.
thyroid, iodine, hypothyroidism
The thyroid gland secretes _____ which regulates serum Ca+ levels. _____ stimulus is reflected in _____ serum Ca+. It also stimulates osteoblast activity and _____ formation.
calcitonin, calcitonin, elevated, bone
There are ___ glands on the posterior surface of the thyroid gland. They secrete _____ _____, which increases blood _____ levels.
4, parathyroid hormone (PTH), Ca2+
Increased blood Ca2+ levels increases _____ of Ca2+, _____ urinary excretion, and _____ bone resorption.
absorption, decreases, increases
The _____ gland is a small gland that sits on top of each kidney.
adrenal
The adrenal _____ is the inner core of the adrenal gland. It acts as both an _____ gland and a sympathetic _____ of the sympathetic nervous system. When stimulated, it releases catecholamines _____ and _____ and a trace of dopamine into the bloodstream.
medulla, endocrine, ganglion, epinephrine, norepinephrine
Epinephrine and norepinephrine increase alertness and prepare the body in several ways for physical activity. They mobilize _____ _____ _____ such as lactate, fatty acids and glucose. Glucose levels are boosted by _____ and _____.
high energy fuels, glycogenolysis, gluconeogenesis
Epinephrine is said to have a ____ ____ effect because it inhibits the secretion of insulin, so the muscles and other insulin-dependent organs absorb and consume less _____. They fall back on alternative fuels such as fatty acids, while the blood _____ is left for use by the brain, which is more _____-dependent.
glucose-sparing, glucose, glucose, glucose
Epineprhone and norepinephrine also increase _____ rate and _____ pressure, stimulate circulation to the _____, increase pulmonary air flow, and raise _____ rate. At the same time, they decrease _____ and _____ production.
heart, blood, muscles, metabolic, digestion, urine
The adrenal _____ surrounds the adrenal medulla and produces more than 25 steroid hormones called corticosteroids or corticoids.
cortex
3 categories of corticosteroids
mineralocorticoids
glucocorticoids
sex steroids
_____ regulate electrolyte balance. It is mainly _____, which stimulates Na+ retention and K+ excretion. Water is retained with _____ by osmosis, so blood volume and blood pressure are maintained.
mineralocorticoids, aldosterone, sodium
_____ is a glucocorticoid that stimulates fat and protein catabolism, gluconeogenesis, and release of fatty acids and glucose into the blood. It helps the body adapt to stress and repair tissues. Long term production of this glucocorticoid under long term stress can lead to _____ suppression.
cortisol, immune
_____ are sex steroid that set the libido throughout life. They play a large role in prenatal male development. They include DHEA, which the tissues convert to _____
androgen, testosterone
_____ is a sex steroid that is small in quantity, but important after _____ for sustaining adult bone mass because the ovaries no longer secrete estrogen–only the adrenals do. Also, other tissues, such as fat, convert _____ into additional estrogen.
estradiol, menopause, androgens
_____ disease is hyposecretion of the entire adrenal gland. This leads to insufficient androgens, mineralcorticoids and glucorticoids, resulting in fatuge, salt cravings, low blood pressure, and pigmentation increase.
Addison’s
The _____ is an exocrine digestive gland with endocrine cell clusters (_____ islets) that is found retroperitoneal, inferior and posterior to the stomach.
pancreas, pancreatic
3 pancreatic hormones
insulin
glucagon
somatostatin
The islets of Langerhans produce _____, while the other 98% of pancreatic cells produce _____ _____.
hormones, digestive enzymes
_____ is secreted by B or beta cells during and after a meal when _____ and _____ _____ blood levels are rising. It stimulates cells to absorb these nutrients and store or metabolize them, lowering blood _____ levels.
insulin, glucose, amino acid, glucose
_____ is secreted by A or alpha cells when blood is hypoglycemic. In the _____ it stimulates gluconeogenesis, glycogenolysis, and the release of glucose into the circulation, _____ blood glucose level. In adipose tissue, it stimulates fat catabolism and release of free _____ _____.
glucagon, liver, raising, fatty acids
_____ is secreted by D or delta cells. It partially suppresses the secretion of _____ and _____. It also inhibits nutrient digestion and absorption which _____ absorption of nutrients.
somatostatin, glucagon, insulin, prolongs
_____ occurs when glucagon, growth hormone, epinephrine, norepinephrine, cortisol, and corticosterone raise blood glucose concentration.
hyperglycermia
hypoglycemia occurs when the hormone _____ lowers blood glucose.
insulin
ovaries and testes are both _____ and _____. _____ products are gonadal hormones, mostly steriods, and _____ products are egg and sperm
endocrine, exocrine, endocrine, exocrine
estradiol, progesterone, and inhibit are _____ hormones.
ovarian
testosterone, weaker androgens, estrogen and inhibin are _____ hormones
testicular
_____ and _____ function in the development of the female reproductive system and physique, including adolescent bone growth. They also regulate the menstrual cycle and sustain pregnancy. They prepare the mammary glands for lacation.
estradiol, progesterone
The ovarian hormone _____ suppresses FSH secretion from the anterior pituitary.
inhibin
microscopic _____ _____ produce sperm
seminiferous tubules
Testosterone and other steroids are secreted from the interstitial cells or cells of _____ nestled between the seminiferous tubules of the testes. They stimulate the development of the male reproductive system in both the fetus and adolescent, as well as sex drive. It sustains _____ production.
Leydig, sperm
In the testes, inhibin is secreted by the _____ cells. It limits _____ secretion in order to regulate sperm production.
sustentacular (Sertoli), FSH
One hormone molecule can trigger the synthesis of many _____ molecules, so a very small stimulus can produce a very large effect.
enzyme
An example of a synergistic hormonal effect is that between _____ and _____ in sperm production
FSH, testosterone
An example of a permissive hormonal effect, in which one hormone enhances the target organ’s response to a second later hormone, is when _____ prepares the uterus for the action of _____.
estrogen, progesterone
An example of an antagonistic hormonal effect, in which one hormone opposes the action of another, is when _____ lower blood glucose and _____ raises it.
insulin, glucagon
Most hormones are taken up and degraded by the _____ and _____ and excreted in _____ or _____
liver, kidney, bile, urine
_____ _____ _____ is the rate of hormone removal from the blood. A _____ _____ is the time required to clear 50% of hormones from the blood.
metabolic clearance rate (MCR), half-life
Stress can be defined as any situation that upsets _____ and threaten’s one physical or emotional well-being. Its 3 phases are _____, _____ and _____.
homeostasis, alarm, resistance, exhaustion
Alarm reaction is mediated by _____ from the sympathetic nervous system and _____ from the adrenal medulla. They prepare the body for fight or flight. Stored _____ is consumed, and there is an increase in _____ to help raise blood pressure, and _____ to promote sodium and water conservation.
norepinephrine, epinephrine, glycogen, angiotensin, aldosterone
In the resistance stage, the pituitary increases its secretion of _____. This stimulates the adrenal cortex to secrete _____ and other glucocorticoids. They promote the breakdown of _____ and _____ into glycerol, fatty acids, and amino acids for _____.
ACTH, cortisol, fat, protein, gluconeogenesis
Cortisol has a glucose-sparing effect, which inhibits _____ synthesis to leave free amino acids for gluconeogenesis. Long term cortisol excess depresses _____ function.
protein, immune
In the exhaustion stage, protein breakdown and muscle wasting take place. There is a loss of glucose homeostasis because the adrenal cortex stops producing _____. _____ promotes water retention and hypertension and conserves sodium and hastens the elimination of K+ and H+ leading to hypokalemia and alkalosis, which can lead to death.
glucocorticoids, aldosterone
_____ are chemical messengers that diffuse short distances and stimulate nearby cells. They are NOT produced in neurons (like neurotransmitters), and NOT trans ported in the blood (like hormones).
paracrines
_____ are formed from mast cells in the connective tissue, and cause relaxation of the smooth muscle of blood vessels.
histamines
_____ relax the smooth muscle of the bladder, instestines, bronchioles, uterus and stimulate contraction of blood vessels. It is both anti-inflammatory and inflammatory.
protaglandins
_____ _____ is the hyposecretion of TH present at birth. It is treated with oral thyroid hormone.
congenital hypothyroidism
_____ is decreased TH from adult hypothyroidism. It is treated with oral thyroid hormone.
myxedema
_____ is any pathological enlargement of the thyroid gland. _____ _____ is caused by dietary iodine deficiency, which prevents the gland from synthesizing TH. Without TH, the pituitary gland receive no feedback and acts as if the thyroid were understimulated. It then produces extra TSH, which stimulates hyertrophy of the thyroid gland.
goiter, endemic goiter
_____ _____ is an autoimmune issue that results in hypothyroidism.
Hashimoto’s Thyroiditis
In _____ disease, autoantibodies mimic the effect of TSH on the thyroid causing hyperthyroidism. Symptoms include exopthalmos (bulging eyes), dry skin, irregular heart beat, and goiter.
Graves
_____ results when the parathyroids are accidentally removed during thyroid surgery. Without hormone replacement therapy, a rapid decline in blood calcium level leads to fatal tetany within 3-4 days.
hypoparathyroidism
_____ is excess PTH secretion. It is caused by a parathyroid tumor. It causes the bones to become soft, fragile and deformed. It also causes Ca2_ and phosphate blood levels to increase, and promotes renal calculi formation.
hyperparathyroidism
_____ _____ is excess cortisol secretion. It can lead to hyperglycemia, hypertension, weakness, and edema, and cause rapid msucle and bonoe loss due to protein catabolism. Some patients exhibit abnormal fat deposition in a “buffalo hump” between the shoulders or a “moon face”.
cushing syndrome
_____ _____ is the hypersecretion of adrenal androgens and commonly accompanies Cushing syndrome. It involves the enlargement of the external sexual organs in children and early onset of puberty. Newborn girls exhibit masculinized genitalia. Masculinizing effects on women include increased body hair, deeper voice and beard growth.
adrenogenital syndrome (AGS)
_____ _____ is the more prevalent metabolic disease in the world. It involves the disruption of metabolism due to the hyposecretion of or inaction of insulin. Symptoms include polyuria (excess urine output), polydipsia (intense thirst), and polyphagia (hunger). It is revealed by elevated blood _____, and the presence of _____ and _____ in the urine.
diabetes mellitus, glucose, glucose, ketones
Type ___ diabetes occurs in 5-10% of cases in the US. It is caused by autoantibodies that attack and destroy pancreatic beta cells. It is treated with insulin.
1
Type ___ diabetes occurs in 90-95% of diabetics. It is caused by the failure of target cells to respond to insulin. It is treated with weight loss and exercise, because loss of muscle mass causes difficulty with regulation of glycermia, and adipose signals interfere with glucose uptake into most cells. Oral medications can improve insulin secretion or target cell sensitivity.
2
CRH secretion would NOT raise the blood concentration of (ACTH, thyroxine, cortisol, corticosterone, glucose)
thyroxine
Which of the following hormones has the least in common with the others? (adrenocorticotropic hormone, follicle-stimulating hormone, thyrotropin, thyroxine, prolactin)
thyroxine
Which hormone would no longer be secreted if the hypothalamo-hypophyseal tract were distroyed?
oxytocin
Which of the following is NOT a hormone? (prolactin, prolactin-inhibiting hormone, thyroxine-binding globulin, atrial natriuretic peptide, cortisol)
thyroxine-binding globulin
Where are the receptors for insulin located?
on the target cell membrane
What would the consequences of defective ADH receptors?
dehydration
Which of these has more exocrine that endocrine tissue? (the pineal gland, the adenohypophysis, the thyroid gland, the pancreas, the adrenal gland)
the pancreas
Which of these cells stimulate bone deposition? (alpha cells, beta cells, C cells, G cells, T cells)
C cells
Which of these hormones relies on cAMP as a second messenger? (ACTH, progesterone, thyroxine, testosterone, estrogen)
ACTH
Prostaglandins are derived from ____ _____.
arachidonic acid
The ______ develops from the hypopphyseal pouch in the embryo.
adenohypophysis
Thyroxine (T4) is synthesized by combining two iodinated molecules of the amino acid ______.
tryosine
growth hormone hypersecretion in adulthood causes a disease called _________.
acromegaly
The dominant hormone in the stage of resistance of the stress response is _______.
cortisol
Adrenal steroids that regulate glucose metabolism are collectively called ______.
glycocorticoids
Testosterone is secreted by the _____ cells of the testis.
interstitial
Target cells can reduce pituitary secretion by a process called _____.
negative feedback inhibition
Hypothalamic releasing factors are delivered to the anterior pituitary by way of a network of blood vessels called the ______.
hypophyseal portal system
A hormone is said to have a/an _______ effect when it stimulates the target cell to develop receptors for other hormones to follow.
permissive
_______ is a process in which a cell increases its numbering of receptors for a hormone.
Up-regulation
