Endocrine System

Describe the thyroid gland structure

-2 lobes joined by a central mass (isthmus) -Inside is composed of hollow structures called follicles - store a sticky colloidal material that TH is made from

How many of the anterior pituitary hormones exert their major effects on NON-endocrine targets? How many are tropic hormones?

-2/6 hormones are non-tropic -4/6 are tropic

What is a hyperglycemic hormone? Which hormones have this role?

-A hyperglycemic hormone is a hormone that raises blood sugar -Glucagon has this role

What does it mean if the hormone has a hypoglycemic effect? Which hormone has this?

-A hypoglycemic hormone is a hormone that lowers blood sugar. -Insulin has this effect

List the full name, gland name, location/target, and the functions of ACTH.

-A.K.A. adrenocorticotropic hormone -Gland name: anterior pituitary gland -Location/target: adrenal cortex/adrenals -Functions: stimulates production of hormones in the adrenal cortex

List the full name, gland name, location/target, and the functions of ADH.

-A.K.A. antidiuretic hormone or vasopressin -Gland name: hypothalamus -Location/target: kidneys -Functions: decrease urine production/output which will increase blood volume (will see blood pressure increase)

List the full name, gland name, location/target, and the functions of FSH.

-A.K.A. follicle stimulating hormone -Gland name: anterior pituitary gland -Location/target: gonads -Functions: stimulates production of follicles in gonads, both male and female; development of gonads (sperm and egg)

List the full name, gland name, location/target, and the functions of GH.

-A.K.A. growth hormone -Gland name: anterior pituitary gland -Location/target: many tissues, primarily bones and muscles -Functions: growth; stimulate metabolism; stimulate cell division; stimulate the use of fat as an energy source and conserve glucose use

List the full name, gland name, location/target, and the functions of LH.

-A.K.A. luteinizing hormone -Gland name: anterior pituitary gland -Location/Target: gonads -Functions: stimulates production of sex hormones, both male and female

List the full name, gland name, location/target, and the functions of PRL.

-A.K.A. prolactin -Gland name: anterior pituitary gland -Location/target: breast -Functions: stimulates production of milk in the mammary glands

List the gland name, location/target, and the functions of calcitonin.

-A.K.A. thyrocalcitonin -Gland name: thyroid -Location/target: bone cells -Functions: decrease blood calcium levels from the bloodstream and increase/deposit it in the bones; activates bone osteoblasts; also triggers the small intestines and the kidneys; (not a function) no absorption and no reabsorption

List the full name, gland name, location/target, and the functions of of TSH.

-A.K.A. thyroid stimulating hormone -Gland name: anterior pituitary gland -Location/target: thyroid gland -Functions: stimulates thyroid gland

What hormones are found in the posterior pituitary gland?

-ADH: antidiuretic hormone -oxytocin

How does drinking alcohol affect ADH?

-Alcohol inhibits (prevent) ADH secretion = large output of urine -Dry mouth and the "hangover" feeling from the dehydration caused by alcohol shutting off the ADH

What are the chemical classification groups of hormones?

-Amino acids -Amino acid-based molecules (proteins, peptides, amines) -Steroids (lipids)-made from cholesterol (sex hormone and those of the adrenal cortex) -Lipids-Nonsteroidal amino acid derivatives -Prostaglandins/paracrine factors

What is the major structural distinction between the anterior and posterior pituitary? (Look at card #10)

-Anterior is composed mainly of glandular cells that secrete hormones -Posterior is made of neuron (nerve cells)

What is the difference between the anterior and posterior of a pituitary gland?

-Anterior is glandular tissue -Posterior is nervous tissue

Discuss the difference between autocrines and paracrines.

-Autocrine: cells make a hormone and the hormone works on itself -Paracrine: cells make a hormone and the hormones work on neighboring cells; does not go to blood

Give examples of autocrines and paracrines.

-Autocrine: prostaglandins-smooth muscles - trigger stimulation -Paracrine: stomach cells trigger other cells to release HCI

In the pancreatic islets _________ cells secrete insulin and ___________ cells secrete glucagon.

-Blank 1: beta -Blank 2: alpha

Describe the mechanisms to trigger a target cell/tissue by nonsteroidal hormones (protein and peptide).

-CANNOT enter the cell - hormone binds to receptor on the target cell's plasma membrane -binding sets off a series of reactions that activates an enzyme/stimulates an enzyme -the enzyme catalyzes a reaction that produces a secondary messenger system/the enzyme stimulates a secondary messenger (Ex: cyclic AMP, G proteins, calcium ions) -the secondary messenger oversees additional intracellular changes that promote the response of the target cell to the membrane/secondary messenger stimulates the cell (See #12)

What are the mechanisms in which hormones trigger changes in cells based upon? What determines which effect will happen? (Look at question 12)

-Chemical make up of the hormone/Chemistry of the hormone -Shape of receptor protein

List the full name, gland name, location/target, and the functions of CRH.

-Full name: corticotropin releasing hormone -Gland name: hypothalamus -Location/target: anterior pituitary -Function: stimulates anterior pituitary to release ACTH which will trigger the adrenal cortex to make hormones

List the full name, gland name, location/target, and the functions of GnRH.

-Full name: gonadotropin releasing hormone -Gland name: hypothalamus -Location/target: anterior pituitary -Function: releases hormone that stimulates the hormones that produce follicles

List the full name, gland name, location/target, and the functions of GHRH.

-Full name: growth hormone releasing hormone -Gland: hypothalamus -Location/target: anterior pituitary -Function: Release protein that triggers long bones to grow; stimulates the release of GH

List the full name, gland name, location/target, and the functions of PTH.

-Full name: parathyroid hormone -Gland name: parathyroid -Location/target: osteoclasts of bones (long) -Functions: trigger the release of calcium from the bone back into the bloodstream; also targets the kidneys and the small intestines (kidneys to reabsorb calcium to the blood and the small intestines to absorb calcium from digested food and into the blood)

List the full name, gland name, location/target, and the functions of TRH.

-Full name: thyroid releasing hormone -Gland name: hypothalamus -Target cell/tissue: anterior pituitary -Function: triggers anterior pituitary to release TSH

Which anterior pituitary hormones are non-tropic?

-GH: growth hormone -PRL: prolactin

List the hormones produced by the pituitary gland.

-GH: growth hormone -PRL: prolactin -FSH: follicle stimulating hormone -LH: luteinizing hormone -TSH: thyroid stimulating hormone -ACTH: adrenocorticotropic hormone

Describe the interrelationships between the endocrine system and the digestive system.

-GI function -absorption -motility -secretory -provides nutrients

List the gland name, location/target, and the functions of gonadocorticoids (androgens).

-Gland name: adrenals -Location/target: gonads, pubic and axillary hair cells, apocrine sweat glands -Functions: stimulates growth spurt early in puberty and controls female sex drive; stimulates secondary sex characteristics in males/females

List the gland name, location/target, and the functions of mineralocorticoids (aldosterone).

-Gland name: adrenals (cortex) -Location/target: kidneys -Functions: regulation of mineral salt concentrations in extracellular fluids; stimulates reabsorption of sodium ions and secretion of potassium ions; plays a role in blood pressure

List the gland name, location/target, and the functions of glucocorticoids (cortisol).

-Gland name: adrenals (cortex) -Location/target: many tissues (bone marrow, kidneys, muscles) -Functions: conversion of amino acids to glucose; decreases WBC; recovery from injury (anti-inflammatory); *regulates energy metabolism and resist to stressors; regulates the immune system and facilitates the stress response*

List the gland name, location/target, and the functions of the ovaries.

-Gland name: female reproductive -Location/target: all over the body -Functions: stimulates the production of estrogen and progesterone after ovulation (by corpus luteum structure); estrogen is important for egg development inside the ovarian follicles; progesterone is important after ovulation for maintaining the integrity of the uterine lining and during pregnancy; progesterone also stimulates hunger

List the gland name, location/target, and the functions of somatostatin.

-Gland name: hypothalamus -Location/target: anterior pituitary -Function: stimulates the release of GH and/or TSH

List the gland name, location/target, and the functions of oxytocin.

-Gland name: hypothalamus -Location/target: breasts and uterus -Functions: stimulate muscle contraction (of the uterine during birth); milk ejection; used in sexual relations

List the gland name, location/target, and the functions of the testes.

-Gland name: male reproductive -Location/target: all over the body -Functions: triggers the production of testosterone, (testosterone aids in the development of gametes, which is responsible for secondary sex characteristics and controls libido)

List the gland name, location/target, and the functions of insulin.

-Gland name: pancreas -Location/target: liver -Function: decrease blood glucose levels; put glucose into storage

List the gland name, location/target, and the functions of glucagon.

-Gland name: pancreas -Location/target: liver and muscles -Functions: increase blood glucose levels

List the gland name, location/target, and the functions of melatonin.

-Gland name: pineal gland -Location/target: brain -Function: control your sleep cycle

List the gland name, location/target, and the functions of thymosin.

-Gland name: thymus gland -Location/target: white blood cells -Function: stimulates the maturation of T-cells

List the gland name, location/target, and the functions of thyroid hormone.

-Gland name: thyroid -Location/target: all cells and tissues of the body -Functions: controls the rate of metabolism and growth/normal tissue growth and development; stimulates cellular respiration/controls rate of oxidizing glucose

List the names, gland name, location/target, and the functions of the adrenal medulla hormones.

-Hormones: epinephrine (adrenaline) and norepinephrine (noradrenaline) -Gland name: medulla of adrenals (triggered by the autonomic nervous system) -Location/target: muscles, nervous system, lungs, heart, digestive system, blood vessels -Functions: fight or flight; emergency hormone; increase in heart rate and respiratory rate; pupils and blood vessels will dilate; digestive movements will stop; sweating; increased blood flow to skeletal muscles *Short lasting hormones*

What is the difference between hypercalcemic and hypocalcemic hormones? Which hormones are classified as each?

-Hypercalcemic: calcitonin (when Ca is high, this will lower it and vice versa with PTH) -Hypocalcemic: PTH (parathyroid hormone)

What hormones are made by the islet cells of the pancreas?

-Insulin -Glucagon

Why is the hypothalamus considered to be a neuroendocrine organ?

-It makes hormones - oxytocin and antidiuretic hormone (ADH) which are transported along the axons of the neurosecretory cells to the posterior pituitary gland for storage -secretion occurs in response to a nerve impulse conduction

Describe the location and structure of the adrenal glands.

-Located on top of the kidneys -Outer=cortex; Inner=medulla

Describe the location and structure of the parathyroid glands.

-Location: back of thyroid -Structure: 4 or 5 small masses posterior to the thyroid

Describe the location and structure of the pineal gland.

-Location: in the posterior of the midbrain -Structure: a small bulb that looks like a pinecone

Differentiate between hormonal. humoral, and neural stimulation of an endocrine gland AND give examples of each. (Do neural)

-Nerve fibers stimulate hormone release -Ex: parasympathetic nervous system trigger adrenal medulla to release epinephrine and norepinephrine in times of stress

List and describe the location of the major endocrine organs.

-Pineal: brain -Pituitary: brain -Thyroid: throat -Parathyroid: back of thyroid -Thymus: on breast bone -Pancreas: behind the stomach -Ovaries: upper pelvic region -Adrenals: on top of kidneys -Testes: scrotum -Hypothalamus: brain (part of nervous system as well)

What is the placenta and how does it function as an endocrine organ?

-Placenta is hCG (human chorionic gonadotropin) -It is high in early pregnancy -It signals maintenance of uterine lining -It is a marker in pregnancy tests -It is considered endocrine

What are the types of thyroid hormones? What does the number indicate?

-T3: triiodothyronine; made by target tissue from conversion of T4 -T4: thyroxine; made by follicles -Number indicates how many iodines there are in the structure

How does the amount of light affect the levels of melatonin produced by the pineal gland?

-The less sunlight, the more melatonin produced -The more sunlight, less melatonin

How do the endocrine system and the nervous system differ in controlling the body?

-The speed is the difference between the two. -The nervous system is designed to go fast (to muscles/glands) using nerve impulses/has a direct route to the responding body part -The endocrine is slow acting, using hormones which are released in the blood

What happens if you have too much or too little amounts of estrogen?

-Too much: increased risk for cancer -Too little: osteoperosis

Describe the pituitary gland.

-a small gland, size of a grape -hangs by stalk on the inferior side of the hypothalamus of the brain -fits in Turks saddle of sphenoid bone -has 2 functional lobes: anterior and posterior

What characteristics are true of ALL anterior pituitary hormones?

-all are proteins (peptides) -all act through second-messenger systems -all are regulated by hormonal stimuli and in most cases negative feedback mechanisms

Activating target cells depends on what factors?

-amount of hormone -amount of receptors -strength of bond between hormone and receptor

What are the types of sex hormones?

-androgen -estrogen -testosterone

Describe androgens.

-androgens change to testosterone changed to estrogen -estradiol is a form of estrogen which is the only form made after menopause

What glands work as just endocrine glands?

-anterior pituitary -thyroid -adrenals -parathyroids

Describe the interrelationships between the endocrine system and the cardiovascular system.

-blood volume -blood pressure -heart contractions -red blood cell production -blood carries hormones

Describe Addison's disease.

-caused by too little aldosterone and cortisone -low sodium, sugar, high K, weight loss, dehydration

Describe Cushing's disease.

-caused by too much cortisol -redistribution of body fat -thin, fragile skin

Differentiate between hormonal. humoral, and neural stimulation of an endocrine gland AND give examples of each. (Do humoral)

-changing blood levels of ions and nutrients will stimulate hormone release -Ex: Parathyroid hormone is prompted by decrease in blood calcium levels

What are diuretics?

-chemicals that antagonize the effects of ADH = water flushed from the body -used to manage edema (water retention in tissues), often in congestive heart failure patients

What are the types of glucocorticoids?

-cortisone -cortisol

Describe the interrelationships between the endocrine system and the lymphatic system.

-depress immune system -immune cells maturation stimulated by hormones

Describe the interrelationships between the endocrine system and the reproductive system.

-development of the reproductive system -birth -breastfeeding -mating

Describe the mechanisms to trigger a target cell/tissue by steroidal hormones (and thyroid hormones).

-diffuse through cell membrane of target cell and into the cytoplasm -enters the nucleus -binds to a receptor protein in the nucleus -binds to a specific site on the cell's DNA (due to the protein) and triggers gene reading -activates certain genes to make mRNA -mRNA is translated the cytoplasm into a protein -Protein stimulates cell activity (See #12)

Describe the interrelationships between the endocrine system and the respiratory system.

-dilates bronchioles -conversion of angiotensin

Differentiate between hormonal. humoral, and neural stimulation of an endocrine gland AND give examples of each. (Do hormonal)

-endocrine organs are triggered into action by other hormones -most common -Use negative feedback to shut off -Ex: hypothalamic hormones trigger anterior pituitary to secrete its hormones and many anterior pituitary hormones trigger other glands to secrete their hormones

What are the types of catecholamines?

-epinephrine -norepinephrine

What hormones are released by the adrenal medulla?

-epinephrine -norepinephrine -"neph"=kidneys

Define synergism and give an example.

-hormones that produce the SAME target effect -Ex: Glucagon and epinephrine both trigger the liver cells to release glucose

Describe the location and structure of the thymus gland.

-located in your breastbone -shrinks as you age

Describe the interrelationships between the endocrine system and the nervous system.

-maturation and function of nervous system -controls other glands (hypothalamus)

Describe the interrelationships between the endocrine system and the muscular system.

-muscle development and metabolism by muscles -does some protection

Describe the interrelationships between the endocrine system and the skeletal system.

-normal skeletal development -bone density -some glands are protected by bones

Define antagonism and give an example.

-one hormone does the opposite effect of another -Ex: glucagon and insulin

Define permissiveness and give an example.

-one hormone works with another hormone-one needs another to exert its complete effects -Ex: development of Reproductive system with its hormones and they thyroid to assist

What glands work as both endocrine and exocrine?

-pancreas -gonads

What are the ways hormones can interact?

-permissiveness -synergism -antagonism

Describe the interrelationships between the endocrine system and the urinary system.

-red blood cell formation -renal function -activate vitamin D

What regulates mineralocorticoids?

-renin---angiotensin -plasma concentrations of potassium and sodium ions -ACTH -atrial natiuretic peptide (ANP)

Describe the interrelationships between the endocrine system and the integumentary system.

-stimulated to produce sebum and provitamin D -increases skin hydraton

What other locations in the body contain hormone-producing cells in fatty tissues and the walls of organs?

-stomach -heart -kidneys -small intestine -adipose tissue

What hormones are produced by the thyroid?

-thyroid hormone -calcitonin

What hormone triggers the secretion of adrenal cortex hormones?

ACTH (adrenocorticotropic hormone)

How does atrial natriuretic peptide help regulate blood pressure?

ANP causes the kidneys to excrete excess sodium and therefore helps to regulate blood pressure and blood volume. (made by cells of the heart)

Compare an endocrine gland with an exocrine gland.

Exocrine glands are glands that secrete their products to the body's surface or into a body cavity through a duct.

What hormone stimulates sperm cell production?

FSH (follicle stimulating hormone)

True or false? A cell cannot have many possible responses to the same hormone.

False. A cell can have many possible responses to the same hormone - depends which secondary messenger system is triggered.

True or false? The organs of the endocrine system are considered large and impressive.

False. Compared to other organs of the body, the organs of the endocrine system are considered small and unimpressive.

True or false? Glands are avascular.

False. Glands have a rich blood supply.

True or false? The posterior pituitary gland is an endocrine gland.

False. It is not an endocrine gland because it does not MAKE the hormones, it simply stores them (from the hypothalamus/hypothalamus makes them).

True or false? Endocrine glands are either exocrine or endocrine, but cannot work as both.

False. Some work as just endocrine and some function as both.

True or false? The endocrine system is described as the first great controlling system of the body.

False. The nervous system is the first.

What are the categories of stimuli that activate the endocrine organs?

Hormonal, humoral, neural

Explain how the endocrine system changes through development.

Hormone levels will fluctuate through different stages of life. Sex hormones are high during adolescence.

Which of the hormones from the pancreas lowers blood glucose? How does it do this?

Insulin; It stimulates glucose intake by cells

Why is the anterior pituitary gland called the master endocrine gland?

It controls so many activities of other glands. Without it the body has a dramatic effect.

What happens with calcitonin as we age?

It is meager or ceases in elderly adults.

Why is the hypothalamus really the MASTER of endocrine activity?

It releases inhibiting and releasing hormones that controls the anterior pituitary gland hormone release---they are connected in blood supply (the capillaries of the hypothalamus are drained by veins which empty into capillaries of the anterior pituitary gland).

How does glucagon raise blood glucose levels?

It stimulates the breakdown of glycogen by the liver and the synthesis of glucose and ketones, thereby raising blood glucose levels.

Which hormone is important for gamete production and maturation of the female reproductive organs?

LH

What hormone primarily stimulates testosterone production by the testes?

LH (luteinizing hormone)

Of the following intestinal hormones: CCK, Secretin, GIP, or Motilin, which is responsible for creating peristaltic waves along the length of the intestines?

Motilin - released about every 90 minutes and causes the smooth peristaltic waves that sweep food toward the terminus of the small intestine. So does GIP-Intestinal Gastrin

_________________are the chief means of regulating blood levels of nearly all hormones.

Negative feedback mechanisms

What hormone stimulates lactation?

PRL (prolactin)

What hormone is produced by the parathyroids?

PTH: parathyroid hormone

Which group of hormones do not enter the blood?

Prostaglandins/paracrine factors

Study diagram.

Study diagram.

What hormone stimulates the thyroid gland?

TSH (thyroid stimulating hormone)

What is the primary effect of a hormone "arousing" a cell?

The attachment of the hormone to the target cell/tissue can cause: -Changes in plasma membrane permeability (more permeable) or electrical state (electrical potential) -Synthesis of proteins or certain regulatory molecules, such as enzymes and hormones, in the cell -Activation or deactivation of enzymes -Stimulate mitosis

Which part of the adrenal glands makes hormones?

The outer cortex

What are the alpha cells of the pancreas and what do they do?

They are cells of the pancreas that produce glucagon.

What are the beta cells of the pancreas? What do they do?

They are cells of the pancreas that produce insulin.

Describe the structure and function of endocrine glands.

They are ductless glands whose products are put into the bloodstream or lymph (hormones) which activate body cells

How do target cells/tissues respond to hormones?

They have specific protein receptors on them to which the hormone attaches.

How are the organs in the endocrine system "unimpressive" compared to the other organs of the body?

They lack structural or anatomical continuity (they are small bits and pieces tucked away in widespread regions/areas of the body).

Why are the adrenal medulla hormones referred to as the "fight or flight" hormones?

They prepare you for emergency situations.

True or false? Lipids go to a receptor protein since they do not dissolve in water.

True

True or false? Some endocrine organs respond to many different stimuli.

True

How much hormone-producing tissue would you need to collect in order to get 1 kg?

You would need ALL endocrine tissue from 8/9 adults.

What hormone is responsible for the reabsorption of sodium and the secretion of potassium?

aldosterone

What hormone is responsible for some secondary sex characteristics in females?

androgens

Describe the thyroid gland location.

base of the throat, inferior to the Adam's apple

Describe the location and structure of the pancreas.

behind the stomach

What does hyperglycemic mean?

blood sugar is high

How is the adrenal medulla similar to the posterior pituitary?

both are made from nervous tissue

How does insulin lower blood glucose levels?

by stimulating glucose uptake by cells -glycogen synthesis by the liver -triglyceride synthesis by adipose cells

Define hormones.

chemical substances (that are synthesized by epithelial cells) that are secreted by cells into the extracellular fluid (the blood) and regulate metabolic activity of other cells in the body

What hormone is most well known for its role in the immune response?

cortisol

Are true hormones endocrine or exocrine?

endocrine

Which hormone is the primary "fight or flight" hormone?

epinepherine

Which hormone of the kidney stimulates blood cell formation?

erythropoietin

Which hormone is important in triggering ovulation at the midpoint of the menstrual cycle?

estrogen

Are most hormones free floating or bound to a protein?

free floating

What are the ways hormones can circulate through the blood?

free floating or bound to a protein

What are corticosteroids?

hormones that are all steroids in structure and that are made by the cortex of the adrenal glands

What is a tropic hormone?

hormones that stimulate their target organs, which are also endocrine glands, to secrete their hormones

The endocrine system is considered a true giant of the body in what way?

in maintaining homeostasis

Which hormone regulates secretion of FSH by the anterior pituitary?

inhibin

Review how a negative feedback mechanism works.

internal or external stimuli triggers hormone release, hormone levels rise, this inhibits the further release of hormones = blood levels of many hormones vary only within a very narrow range

What hormone is made by the pineal gland?

melatonin

What are the types of corticosteroids?

mineralocorticoids: aldosterone

How does the amount melatonin affect people?

more melatonin=more sleepy and depressed

Which hormone is important during pregnancy?

progesterone

What role do renin, angiotensin II, and atrial natriuretic peptide (ANP) have on the mineralocorticoids?

regulates mineralocorticoids

All of the hormones secreted by the adrenal cortex are of this chemical composition:

steroids (lipids)

Which hormone is responsible for male libido?

testosterone

What is a target cell/tissue?

the specific cell type or tissue type that a hormone affects

What hormone is produced by the thymus gland?

thymosin