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