A&P Chapter 11 Endocrine

Posterior Pituitary

Antidiuretic Hormone (ADH) Oxytocin (OT)

Heart (Atria)

Atrial Natriuretic Hormone (ANH)

Placenta

Chorionic Gonadotropin Estrogens Progesterone

Name the hormones produced by the zones or areas of the adrenal cortex.

Corticoids (steroid hormones)

_________ glands are ductless and secrete their products, called ____________, into intercellular spaces where they diffuse into the blood.

Endocrine ; Hormones

What is the difference between Endocrine and Exocrine Glands?

Endocrine glands are any of the ductless glands that are part of the endocrine system and secrete hormones into intercellular spaces, where they diffuse into the bloodstream. Exocrine Glands secrete their products into ducts that empty onto a surface or into a cavity (sweat glands).

Adrenal Medulla

Epinephrine (Epi) Norepinephrine (NR)

Ovary

Estrogen Progesterone

What glands secrete their products into the ducts that empty onto a surface or into a cavity?

Exocrine Glands

List conditions that may occur from hyposecretion and hypersecretion of the growth hormone, thyroid gland, adrenal cortex, and pancreas

GH (hyposecretion): causes hypoglycemia- lower than normal blood glucose concentration GH (hypersecretion): causes hyperglycemia- higher than normal blood glucose Thyroid Gland (hyposecretion): causes hypothyroidism- undersecretion of thyroid hormones Thyroid Gland (hypersecretion): causes hyperthyroidism- oversecretion of thyroid hormones Adrenal Cortex (hypersecretion)- Stress Adrenal Cortex (hyposecretion)- atrophy of thymus

Gastrointestinal (GI) Tract

Ghrelin

Pancreatic Islets

Glucagon Insulin

Explain and Give an example of a negative feedback loop for the regulation of hormone secretion

Insulin, when it is released from endocrine cells in the pancreas it lowers "blood sugar levels" or glucose concentration in the blood.

Describe the structure of the pituitary gland

It is a small, but mighty structure, no larger than a pea. It is really 2 glands-each a different type. One is ) called the anterior pituitary gland (adenohypophysis and the Posterior Pituitary Gland (neurohypophysis).

Explain why a second messenger system is necessary for nonsteroid hormones but not for steroid hormones

It is because steroid hormones can pass directly through the plasma membrane of the target cell, but the nonsteroid hormones need the second messengers to be able to reach the target cell.

Where is the pituitary gland located?

It is located buried deep in the cranial cavity, it is securely within a "seat" called the Sella Turcica formed by two bony projections at the top of the sphenoid bone.

Fat Storing Cells

Leptin

What would be the effect on the body if the thyroid gland were removed?

Lessened mental and physical vigor Weight Gain Loss of Hair Swelling of the Tissues

Pineal Gland

Melatonin

Adrenal Cortex

Mineralocoticoids (MCs); aldosterone Glucocoticoids (GCs); cortisol Sex Hormones (androgens)

Explain and Give an example of a positive feedback loop for the regulation of hormone secretion

Muscle Contractions, during labor the muscle contractions that push the baby through the canal become stronger and stronger by the positive feedback mechanism that regulates secretion of the hormone oxytocin.

The two major classes of hormones are __________ hormones and ____________ hormones.

Nonsteroid ; Steroid

Parathyroid

Parathyroid Hormone (PTH)

Explain the function of prolactin and oxytocin

Prolactin stimulates the breast development necessary for eventual lactation (milk secretion). Oxytocin stimulates contraction of the smooth muscle of the pregnant uterus and is believed to initiate and maintain labor.

Explain the difference between prostaglandins and hormones.

Prostaglandins "Tissue Hormones" are lipid substances found in a wide variety of tissues. Hormones are a substance secreted by an endocrine gland.

Pick a body function (regulation of glucose or calcium levels in the blood) and explain how the interaction of hormones is used to help maintain homeostasis

Regulation of body temperature, the Releasing Hormones and Inhibiting Hormones combine and allow the nervous system and endocrine system to influence homeostasis

Hypothalamus

Releasing Hormone (RHs) Inhibiting Hormones (IHs)

What are some of the body functions that can be influenced by prostaglandins?

Respiration Blood Pressure GI secretions Inflammation Reproductive System

Explain the difference between T3 and T4. What is unique about the thyroid gland?

T4 is the more abundant, contains 4 atoms of iodine. T3 is more potent and considered the principal thyroid hormone, contains 3 iodine atoms.

A cell or body organ that has receptors for a hormone that triggers a reaction is called ____________.

Target Organ

Testis

Testosterone

If a doctor discovered a patient had very low levels of thyroxine but high levels of TSH, would the patient's problems be in the thyroid gland or the pituitary gland? Explain.

The pituitary gland because it secretes TSH (Thyroid Stimulating Hormone).

Explain the mechanism of action of steroid hormones

They do not occur by the second messenger system. They can pass intact directly through the plasma membrane of the target cell.

Explain the mechanism of action of nonsteroid hormones

They work as a "First Messenger" and work according to the second messenger mechanism. They work as a "Lock and Key" model.

Thymus

Thymosins

Name the four tropic hormones released by the anterior pituitary gland and briefly explain their function.

Thyroid Stimulating Organ (TSH) stimulates the thyroid gland to increase secretion of thyroid hormone. Adrenocorticotropic Hormone (ACTH) increases the size of the adrenal cortex and allows it to secrete larger amounts of hormones; especially cortisol. Follicle-Stimulating Hormone (FSH) stimulates the primary ovarian follicles in an ovary to start growing and developing to maturity (ovulation). Stimulates follicle cells to secrete estrogens. In males it stimulates the seminiferous tubules to grow and form sperm. Luteinizing hormone (LH) stimulates a follicle and ovum to complete maturity, stimulates follicle cells to secrete estrogen, and causes ovulation. In males it simulates interstitial cells in the testes to develop and secrete testosterone.

Anterior Pituitary

Thyroid-Stimulating Hormone (TSH) Adrenocorticotropic Hormone (ACTH) Follicle-Stimulating Hormone (FSH) Luteinizing Hormone (LH) Growth Hormone (GH) Prolactin Hormone (PRL) (lactogenic hormone)

Thyroid

Thyroxine (t4) and Triidothyronine (T3) Calcitonnin (CT)

Antidiuretic hormone (ADH); ______________________________.

accelerates water reabsorption in the kidney

Epinephrine

adrenaline; secretion of the adrenal medulla

This part of the pituitary gland is made of glandular tissue; _________________________.

anterior pituitary (adenohypophysis)

Glucocorticoids

category of hormones that influences food metabolism; secreted by the adrenal cortex

What is a Target Cell?

cell acted on by a particular hormone and responding to it

One example of a second messenger system involves conversion of ATP into ___________.

cyclic AMP (cAMP)

Calcitonin

decreases level of calcium in the blood

Parathyroid Hormone

hormone produced by the parathyroid gland that increases the concentration of calcium in the blood

Glucagon

hormone secreted by alpha cells of the pancreatic islets

Chorionic Gonadotropins

hormone secreted by the developing placenta during pregnancy and that has a gonad stimulating effect

Atrial Natriuretic Hormone

hormone secreted by the heart cells that regulates fluid and electrolyte homeostasis

Insulin

hormone secreted by the pancreatic islets

Mineralcorticoids

hormone that influences mineral salt metabolism; secreted by the adrenal cortex; aldosterone is the chief mineralcoticoid

Melatonin

important hormone produced by the pineal gland that is believed to regulate the onset of puberty and the menstrual cycle; also referred to as the third eye because it responds to levels of light and is thought to be involved with the body's internal cycle

Thyroxine

is made in the thyroid gland

Explain the function of growth hormone

it speeds up the movement of digested proteins (amino acids) out of the blood and into the cells, and this accelerates the cells anabolism (building up of amino acids to form tissue proteins. The anabolic action promotes normal growth.

Explain the function of aldosterone

its main function is to increase the amount of sodium and decreases the amount of potassium in the blood.

The hormone receptors for nonsteroid hormones are located____________, whereas the receptors for steroid hormones are located _____________.

on the cell membrane ; in the nucleus

This hormone is released by the posterior pituitary and stimulates the contraction of the pregnant uterus

oxytocin

This part of the pituitary gland is made of nervous tissue; ______________.

posterior pituitary (neurohypophysis)

The hormone oxytocin is released by the ______________ but is made in the _______________.

posterior pituitary gland ; hypothalamus

Explain the function of glucocorticoids

process in liver cells that that converts amino acids, or glycerol to glucose

This hormone is released by the anterior pituitary and stimulated breast development during pregnancy and is necessary for eventual milk production.

prolactin

"Tissue Hormonesis another name for ______________.

prostaglandins

Explain the function of ADH

regulates the fluid balance of the human body and accelerates the reabsorption of water from urine in the kidney tubules back into the blood. The term antidiuretic means "acting against an increase in urine volume"

What is a Hormone?

substance secreted by an endocrine gland

Explain the function of the hypothalamus in the endocrine system

the combined nervous and endocrine functions of the hypothalamus allow the nervous system to influence many endocrine functions. The hypothalamus plays a dominant role in the endocrine system by providing homeostasis in the body. Examples: Regulation of Body Temp Appetite Thirst

A tropic hormone secreted by the anterior pituitary gland is ___________________

thyroid stimulating hormone adrenocorticotropic hormone luteinizing hormone

What is Hyposecretion?

too little of a substance is being secreted

What is Hypersecretion?

too much of a substance is being secreted