gland
A ___ is an organ that consists of cells that secrete materials into other regions of the body.
Exocrine glands; sweat glands, mucous glands, & salivary glands
___ secrete nonhormonal chemicals into ducts, which transport the chemicals to a specific location inside and outside the body. What are 3 examples of exocrine glands?
Endocrine glands
___ are ductless glands that are located throughout the body. Endocrine Glands secrete hormones into the bloodstream through the fluid that surrounds their cells.
hormone
A ___ is a chemical signal, made in one place and delivered to another, that regulates the body's activities.
bloodstream
Hormones are compounds that are secreted in small amounts into the ___ and that influence the activity of distant cells.
target cells
The hormones travel to a specific tissue or organ called ___.
specific response
At the target cells, hormones elicit a ___.
homeostasis
Hormones are essential to maintaining ___. It is defined as a stable internal environment.
Neuroendocrine System
The Endocrine System and Nervous System are so closely linked that they are often are considered a single system called the ___.
arrival of the hormone
A hormone does not seek out a particular organ; instead, the organ is awaiting the ___.
Receptors
___ are proteins that are located both inside the cytoplasm and on the surface of a target cell.
receptor proteins
Certain cells respond to one hormone and not another, depending on their ___.
Hormones
___ are chemical messengers that influence the metabolism of the recipient cell.
Steroid hormones
___ are hormones the body synthesizes from cholesterol.
Amino acid-based hormones
___: (peptide hormones) are hormones made of amino acids.
Adrenal Cortex, the Ovaries, and the Testes; plasma membrane; receptors
Steroid hormones are produced by the ___, the ___, and the ___. Steroid hormones do not bind with the ___. ___ of the target cells can enter the cell and the cell's nucleus freely.
all other glands
Amino acid-based hormones are produced by ___ except adrenal cortex, the ovaries, and the testes.
Amino acid-based hormones
___ are polar molecules (posses both positive and negative ends) and they cannot pass through the plasma membrane of their target cells. These hormones must send their message from outside the target cell, a two-messenger system is commonly required for t
THE FIRST MESSENGER; THE SECOND MESSENGER
Peptide hormones attaches to receptors on the plasma membrane, ___, carrying the message from the endocrine gland to the cell surface, and pass the message to another molecule inside the cytoplasm, ___.
Cyclic AMP (c-AMP)
In many cases, the hormone-receptor complex indirectly activates an enzyme that converts molecules of ATP to ___ inside the target cell.
endocrine system
The ___ plays an important role in the maintenance of homeostasis because it affects the activities of cells, tissues, and organs throughout the body.
hormone secretions; feedback mechanism
To maintain homeostasis, ___ must be tightly regulated. Most hormones are controlled by a ___.
feedback mechanisms: In a feedback mechanism, the last step in a series of events controls the first step.
The endocrine system uses ___ to respond and adjust to changes that occur in and outside the body.
NEGATIVE FEEDBACK
Most hormone systems use ___, in which release of an initial hormone stimulates the release or production of other hormones or substances that inhibits the further release of the initial hormone.
POSITIVE FEEDBACK
In ___, the release of an initial hormone stimulates the release or production of other hormones or substances, which stimulates the further release of the initial hormone.
nervous, endocrine, and circulatory
How do negative feedback mechanisms regulate hormone release? The body produces more than 30 hormones, and therefore it must be able to regulate the release of these hormones. Negative feedback mechanisms in the body involve interactions of the ___, ___,
hypothalamus
The ___ is the part of the brain and nervous system that regulates body temperature, breathing, hunger and thirst. It is the master switchboard for the endocrine system. It is located beneath the thalamus in the brain, and it regulates our body's internal
two lobes of the pituitary gland; nervous; endocrine
The hypothalamus regulates the ___ by releasing inhibiting hormones. The hypothalamus links the ___ system to the ___ system.
NEUROSECRETORY CELLS
___ of the hypothalamus produce hormones that either are stored in the pituitary gland or regulate the pituitary's activity.
hypothalamus
The ___ is continuously checking (monitoring) conditions inside your body.
hypothalamus
If your internal environment starts to get out of balance, then the ___ has several ways to set things right again. It will send out a nerve signal to another part of the brain (the medulla oblongata) to speed up or slow down your heart rate. Or it will s
pituitary gland; Posterior Pituitary and the Anterior Pituitary
The ___ is a small gland about 1 cm in diameter is connected to the hypothalamus by a stalk-like structure. It has two portions called ___ and ___.
posterior pituitary
The ___ stores two hormones, called vasopressin (or ADH) and oxytocin. Both hormones are produced by and released from the hypothalamus.
ANTIDIURETIC HORMONE (ADH) OR VASOPRESSIN
___ causes the kidneys to form more concentrated urine, conserving water. Thus, the kidneys produce urine with a high solute concentration.
OXYTOCIN
___ stimulates contractions of the uterus during labor and it also causes the release of milk from the breast of a nursing mother.
RELEASING HORMONES
ANTERIOR PITUITARY: Neurosecretory cells in the hypothalamus also produce and secrete ___, which stimulate endocrine cells of the anterior pituitary lobe to produce and secrete hormones.
RELEASE-INHIBITING HORMONES
ANTERIOR PITUITARY: Other hypothalamic cells which produce ___, which inhibit the production and secretion of the anterior pituitary hormones.
nervous system
ANTERIOR PITUITARY: Releasing hormones and release-inhibiting hormones are produced in response to various stimuli that are processed by the ___.
Master Gland
The Anterior Pituitary is sometimes called the ___ because it controls the secretion of other endocrine glands.
GROWTH HORMONE (GH)
Hormones Produced by the Anterior Pituitary: ___ promotes cell division, protein synthesis, and bone and muscle growth.
PROLACTIN
Hormones Produced by the Anterior Pituitary: ___ causes the mammary gland in breast to develop and produce milk. It also plays a role in carbohydrate and fat metabolism.
MELANOCYTE-STIMULATING HORMONE
Hormones Produced by the Anterior Pituitary: ___ stimulates the melanocytes of the skin to increase their production of the dark pigment melanin.
THYROID-STIMULATING HORMONE (TSH)
Hormones Produced by the Anterior Pituitary: ___ regulates the thyroid to produce and release Thyroxin and Triiodothyronine.
ADRENOCORTICOTROPIC HORMONE (ACTH)
Hormones Produced by the Anterior Pituitary: ___ stimulates the adrenal cortex. It causes the adrenal cortex to produce and release Cortisol and Aldosterone.
FOLLICLE-STIMULATING HORMONE (FSH) and LUTEINIZING HORMONE (LH)
Hormones Produced by the Anterior Pituitary: GONADOTROPIC HORMONES called the ___ and ___ stimulate the gonads, which is the testes in males and the ovaries in females. It causes the gonads to secrete sex hormones and stimulates gamete (sperm and egg) pro
thyroid gland
The ___ is located at the base of the neck just below the larynx.
THYROID-STIMULATING HORMONE (TSH); It produces THYROXIN, TRIIODOTHYRONINE, and CALCITONIN
___ regulates the thyroid gland. It produces ___, ___, and ___.
THYROXIN and TRIIODOTHYRONINE
Hormones produced by the thyroid gland: ___ and ___ stimulate and maintain metabolic activities, normal heart rate, blood pressure, and body temperature. They also promote carbohydrate usage over fat usage for energy.
CALCITONIN
Hormones produced by the thyroid gland: ___ inhibits the release of calcium from bones and regulates the level of calcium in the blood.
iodine
In order to produce Thyroxin and Triiodothyronine, the thyroid gland requires ___, which is found in iodized salt.
Goiter
___ is the swelling of the thyroid gland as a result of iodine deficiency.
cellular respiration rate
Decreased levels of thyroxin causes a decrease in the ___. Then, cells produce less energy and become less active.
HYPERTHYROIDISM
___ is too much thyroxin which results in nervousness, elevated body temperature, increased heart and metabolic rates, increased blood pressure, and weight loss. It can be treated with medication or by surgical removal of part of the thyroid gland.
HYPOTHYROIDISM
___ is not enough thyroxin and results in lower metabolic rates and body temperature, lack of energy, and weight gain. In some cases it is associated with a goiter. It can be treated with supplementary thyroxin.
CRETINISM
Hypothyroidism in infants affects normal development of the skeleton, muscular and nervous systems and results in a condition called ___, which is characterized by dwarfism and mental retardation.
Parathyroid glands
___ are attached to or embedded in the back surface of the thyroid gland, two in each lobe.
PARATHYROID HORMONE (PTH)
Parathyroid glands produce ___ which regulates the calcium levels in the blood by increasing the reabsorption of calcium in the kidneys and by increasing the uptake of calcium from the digestive system. This hormone is important in promoting proper nerve
Tetany
A loss of the parathyroid glands cause a drop in the level of calcium in the blood, which may result in violent muscular spasms called ___. It can be relieved by the administration of large amounts of PTH and injections of calcium.
Adrenal Cortex; Adrenal Medulla
Adrenal Glands: One gland is located on the top of each kidney. They are composed of two very different types of tissue. Outer tissue is called the ___. Inner tissue is called the ___.
ADRENOCORTICOTROPIC HORMONE (ACTH)
The outer portion of the adrenal cortex makes up 80% of the mass of the gland. The adrenal cortex responds to ___, which is secreted by the pituitary gland.
CORTICOSTEROIDS
The adrenal cortex produces more than two dozen hormones called ___, which are steroid hormones and essential for normal body function.
Aldosterone
Hormones produced by the adrenal glands: ___ regulates the reabsorption of sodium and the excretion of potassium by the kidneys. This affects water and salt balance in the body.
Cortisol
Hormones produced by the adrenal glands: ___ affects carbohydrate, protein and fat metabolism. It also helps people cope with stress.
Addison's disease
Diseases associated with the adrenal gland: A decrease in the activity of the adrenal cortex can result in ___. It causes weight loss, low blood pressure, and general weakness. Death may occur due to heart failure. People with this disease receive regular
Cushing Syndrome
Diseases associated with the adrenal gland: A increase in the activity of the adrenal cortex can result in ___. It causes obesity, increase in blood sugar levels, high blood pressure, and weakening of bones. Treatment for this involves decreasing the secr
adrenal medulla
The ___ is a specialized part of the sympathetic nervous system.
ADRENALINE (EPINEPHRINE); NORADRENALINE (NOREPINEPHRINE)
The adrenal medulla secretes two amino acid-based hormones called NEUROHORMONES called ___ and ___.
adrenaline; noradrenaline
Adrenal Medulla: The "fight or flight" hormones cause nerve impulses from the Sympathetic nervous system, which results in the secretion of ___ and ___.
Adrenaline
___ increases heart rate, blood pressure, and blood supply to the skeletal muscles, increases the conversion of glycogen to glucose, and stimulates the rate of metabolism. It is more powerful in its actions and makes up 80 percent of the adrenal medulla's
Noradrenaline
___ stimulates the heart muscle, increases the rate and strength of the heartbeat.
gonads
The ___ are the ovaries in females and the testes in males. They are gamete producing organs that also produce a group of steroid sex hormones.
Estrogens
___ are required for the development of ova and the formation of physical characteristics (secondary sex characteristics) associated with the female. These characteristic include the development of the female reproductive system, the menstrual cycle begin
Progesterone
___ prepares the uterus for the arrival of the developing embryo and controls the menstrual cycle.
androgens
The Testes produce sperm. The Testes produce ___, which affect cells throughout the body.
Testosterone
___ is an androgen that regulates male secondary sex characteristics.
Androgens
___ are required for normal sperm production and the development of physical characteristics( secondary sex characteristics) associated with puberty in males. These characteristics include growth of facial hair, increase in body size, and deepening of the
pancreas
The ___ is located behind the stomach. It is both an exocrine gland and an endocrine gland.
Islets of Langerhans
The hormone producing portion of the pancreas consists of clusters of cells that resemble islands called the ___. Each islet is composed of BETA CELLS which secrete INSULIN, and ALPHA CELLS which secrete GLUCAGON. These two hormones insulin and glucagon r
insulin; glucagon
PANCREAS: ___ stimulates its target cells to take up and use glucose. This action lowers blood glucose levels; ___ stimulates its cells to breakdown stored glycogen and increase glucose levels in the blood.
Diabetes Mellitus; Type I or Juvenile Onset; Type II or Adult Onset
When there is an under secretion of insulin, a condition called ___ occurs. ___ occurs before age 25. These individuals produce little or no insulin production. It requires a strict diet and daily injections of insulin; ___ occurs after age 40. These indi
Hypoglycemia
___ is caused by excess insulin or low blood sugar. This disorder occurs when glucose is stored rather than being properly delivered to the cells of the body, which causes cells to starve to death. This leads to a lower blood glucose concentration and sub
Hyperglycemia
___ is caused by low insulin or high blood sugar. It can cause nausea and rapid Breathing, possibly leading to oxygen deficiency, circulatory and nervous system failure, diabetic coma or death.
thymus gland
The ___ is located beneath the sternum and between the lungs. It consists mostly of T-cells and plays a role in the development of the immune system.
thymosin
The thymus gland secretes ___, an amino acid based hormone that stimulates the formation of T-cells , which help defend the body from pathogens.
pineal gland
The ___ is located near the base of the brain.
melatonin
The pineal gland secretes the hormone called ___. Concentrations of this increase sharply at night and decrease dramatically during the day. This cyclic release indicates that it helps regulate our sleep cycle.