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103 Cards in this Set
- Front
- Back
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NERVOUS AND ENDOCRINE SYSTEM
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The nervous and endocrine system work together to maintain homeostatis & in the co-ordination of body functions. The endocrine system used chemical messengers called HORMONES, while the nervous system uses electrical impulses & chemical messengers called NEUROTRANSMITTERS. The reason that these two systems work so closely together is that the nervous system is able to produce fast, almost instantaneous response, while the endocrine system takes longer to respond, but is longer acting. This means that the nervous system can respond immediately& then be followed up & supported by the endrocrine system, which maintains the response
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Endocrine glands
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Ductless glands that empty their hormonal products into the interstitial fluid surrounding the secretory cells. From here they diffuse directly into the blood stream, then travel via the blood to the target tissues
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Hormones
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A hormone is a chemical messenger that’s released from one part of the body, but regulates the activity of another part of the body. Most hormones travel in the bloodstream to reach & affect their target tissues. Both hormones and neurotransmitters are chemical messengers that act by binding to receptors on or in their target cells. Some substances act as both hormones & neurotransmitters eg adrenalin(epinephrine) & noradrenalin(norepinephrine).
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Endrocrine system
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The endocrine system consists of endocrine glands & hormone secreting cells. Endocrine glands in the body include the pituitary, thyroid, parathyroid, adrenal & pineal glands. Organs and tissues that also contain hormone-secreting cells, but are not actually glands, include the hypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart, adipose tissue and placenta.
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Hormone activity
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Hormone activity depends on hormone receptors & certain characteristics of the hormones themselves. Hormones can only act on certain cells by binding to specific receptors located on or inside these cells. This means that hormones can only affect cells that contain receptors for that hormone-if there are no receptors for a particular hormone then that hormone has no affect on the cell. The number of receptors may change depending on the amount of hormone available-excess hormone causes down regulation(a reduction in the number of receptors), whilst a lack of hormone causes up regulation(an increase in the number of receptors). When there are fewer receptors the cells response to the hormone is reduced & vice versa.
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Circulating and local hormones
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Hormones may be classified as either circulating or local hormones, depending on the distance they travel to interact with their target cells:circulating hormones are the most common type. They travel in the blood to act on distant target cells. The effects of circulating hormones are usually longer lasting, as they may remain in the blood to exert their effects for minutes, & sometimes hours. Local hormones act on target cells close to their site of release. Local hormones are usually inactivated quickly, so their effects are shorter lasting. There are two types paracrines-that act on neighbouring cells and autocrines-that act on the same cell that secreted them
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Chemical classes of hormones
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Hormones are classified according to their solubility as either water or lipid soluble. This classification is also functionally useful because the water & lipid soluble hormones exert their effects in different ways. Water-soluble hormones- Hormones that are water-soluble are transported freely in the blood & attach to receptors on the OUSTIDE of a cell’s plasma membrane. Lipid-soluble hormones-Hormones that are lipid-soluble(steroid & thyroid hormones) are transported in the blood attached to transport proteins, diffuse through the plasma membrane to attach to receptors INSIDE their target cells
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Hormones-Bind to their receptors
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Once hormones bind to their receptors it begins a series of events that alter the activity of the cell. The effects the hormones are varied, but examples include*The regulation of an enzyme *The secretion of a cellular constituent *Synthesis of a protein *An alteration in the plasma membrane permeability
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Hormone effects and response
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Also note that a hormone may have a variety of effects depending upon the cell it is acting on. For example, insulin stimulates glycogen synthesis when it acts on liver cells, but stimulates triglyceride synthesis when acting on adipose tissue. It is also important to note that the response of a target cell to a hormone depends upon factors such as the concentration of the hormone, the greater the concentration the more vigorous the response the number of receptors on a target cell, the more receptors the greater the response the effect of other hormones on the same target cell. Some hormones have a synergistic action (eg thyroid hormones & epinephrine enhance each others effects), whilst some have an antagonistic action(eg insulin & glucagon oppose each others actions).
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Control of hormone secretion
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The secretion of hormones is regulated by signals from the nervous system nerve impulses are sent from the brain to a hormone-secreting gland or cell, & stimulate the secretion of the hormone Chemical changes in the blood Changes in the blood chemistry are monitored by nerves & can trigger hormone release. Eg the concentration of calcium ions in the blood regulates the secretion of parathyroid hormone (PTH) Other hormones Some hormones trigger or suppress the secretion of other hormones. Eg thyroid stimulating hormones (TSH) stimulates the release of thyroid hormones (T3 & T4) The secretion of most hormones is co-ordinated by negative feedback systems.
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Glucagon
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Increases the blood glucose concentrations, by stimulating the liver to manufacture glucose and release it to the blood. The secretion of glucagon is stimulated by low blood glucose concentrations, as a result this hormone is secreted in between meals when blood glucose levels fall.
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Pineal gland
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The pineal gland is small in size & is part of the epithalamus of the brain. The physiological roles of the pineal gland are still not completely understood, however it is known that this gland secretes the hormone melatonin. Melatonin is an amine hormone, that is derived from serontonin. Larger amounts of melatonin are secreted in darkness, & smaller amounts in strong sunlight. It is thought that melatonin has the following functions-Sets the body clock and co-ordinates sleep/awake times. Acts as a potent antioxidant. Possibly influences reproduction in an unknown way.
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Hypothalamus
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Hypothalamus is part of the brain and important in regulating our autonomic immune system.Known as the master gland of the endocrine system, it allows the endocrine and nervous system to work together to maintain homeostatis. Referred to as the neuro-endocrine system, to join the two systems into one super system. It receives nerve impulses fromvarious areas of the brain,as well as sensory input from internal organs and the retina. It secretes at least 9 different hormones, which in turn control the secretion of hormones by the pituitary gland, which in turn secretes hormones that control the activity and hormone secretion in other glands and cells. With the pituitary gland the hypothalamus play a role in the regulation of practically all areas of growth, development, metabolism and homeostatis. Hypothalamic hormones-GHRH growth hormone releasing hormone GHIH growth hormone inhibiting hormone TRH thyroid releasing hormone CRH Corticotropin releasing hormone GnRH Gonadrotopin releasing hormone PRH prolactin r
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Pituitary gland
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Looks like an upside down mushroom, which hangs underneath the hypothalamus. It has two anatomically and functionally separate lobes. ANTERIOR PITUITARY(adenohypophysis)-connected to the hypothalamus by blood vessels. The anterior portion of the gland is larger than the posterior,and makes up about ¾ of the size of the gland. POSTERIOR PITUITARY(neurohypophysis)- receives hormones synthesised by the hypothalamus, which are then passed down to the pituitary by neurons. It stores these hormones and releases them when necessary.
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Anterior pituitary
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The secretions from the anterior pituiutary is controlled by the hypothalamus, which secretes hormones that either stimulate or inhibit the release of hormones from this location. The main hormones secreted by the anterior lobe of the pituitary are- HGH human growth hormone, TSH thyroid stimulating hormone: T3 and T4, ACTH adrenocorticotrophic hormone, FSH follicle stimulating hormone, LH luteinising hormone, PRL prolactin and MSH melanocyte-stimulating hormone.
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Gland
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Organ specialized to secrete or excrete substances for further use in the body or for elimination
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Exocrine glands
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Glands that have ducts through which their secretions are carried into body cavities, into the lumen of an organ, or to the external surface of the body. These secretions are NOT hormone. Exocrine glands include, sweat, sebaceous, mucous and digestive glands.
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Peptide hormones
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A molecule formed by linking amino acids in a chain. Usually, but not always, contains fewer than 50 amino acids.
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Amine hormone
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Derivatives of single amino acids, either tyrosine or tryptophan
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Pituitary gland
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Neuroendocrine gland located beneath the hypothalamus of the brain. Anterior lobe secretes LH, FSH, GH, TSH, ACTH, and prolactin (PRL). Posterior lobe releases the hormone oxytocin and vasopressin (ADH) that are produced by hypothalamic neurons.
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Thyroid stimulating hormone (TSH)
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Anterior pituitary hormone that stimulates the synthesis and secretion of thyroid hormones T3 and T4 by the thyroid gland.
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Follicle stimulating hormone
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(FSH)
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Luteinizing hormone
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(LH) Anterior pituitary hormone that aids maturation of cells in the ovary, triggers ovulation in females, and stimulates the production of estrogen and progesterone. In males, causes the interstitial cells of the testis to produce testosterone.
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Estrogen
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Female sex hormones produced by the ovary; during puberty promotes development of secondary sex characteristics and is necessary for the production of the ovum.
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Progesterone
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Steroid hormone secreted by the ovary and placenta. Regulates ovarian function, uterine lining, breast development, and is required for pregnancy.
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Testosterone
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Male sex hormone produced by the testes; during puberty promotes development of the secondary sex characteristics, and is necessary for normal sperm production.
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Gonadotropins
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Consist of follicle stimulating hormone and luteinizing hormone, both released by the anterior pituitary
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Adrenocorticotropic hormone
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(ACTH) or corticotrophin, Anterior pituitary hormone that stimulates the production and secretion of glucocorticoids (mainly cortisol) by the adrenal cortex.
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Glucocorticoids
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Adrenal cortex hormones that regulate blood glucose levels and aid the body in resisting stress.
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Adrenal cortex
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Outer portion of the adrenal gland that produces steroid hormones
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Growth hormone
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(GH)
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Somatomedins
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(IGF) Insulin-like growth factors, synthesized by the liver, chemical factors required for the growth of effects of GH. Both IGF and growth hormone are required for growth of cartilage, hence full adult height of the skeleton
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Prolactin
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(PRL) Hormone produced by the anterior pituitary gland that stimulates lactation in females after birth. Although present in males, its actions are unknown.
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Pineal gland
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Endocrine gland located in the diencephalon of the brain. Secretes the amine, melatonin
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Melanocyte-stimulating hormone MSH
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Not well understood, thought to possible influence brain activity. When found in excessive amounts, it causes darkening of the skin due to increased melanocyte activity.
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Thyroid gland
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The thyroid gland is found in the neck, situated on either side of the trachea and shaped like a butterfly.Produces two different hormones that increase the basal metabolic rate (BMR), they are tetraiodothyronine(T4 or thyroxine) and triiodothyronine (T3). The number t3 and t4 refer to the number of iodine atoms they contain. It also releases a hormone called calcitonin which helps to regulate calcium homeostatis. Thyroid hormone levels are controlled by negative feedback. When levels of thyroid hormone drop in the blood the hypothalamus secretes TRH, which stimulates the anterior pituitary gland to release TSH, which then stimulates the thyroid gland to secrete thyroid hormones. By the increasing metabolism, T3 and T4 increase the rate at which nutrients are catabolised and energy is produced. This will help maintain body temperature. Thyroid hormones also enhance the effects of epinephrine and norepinephrine & are essential for growth and development. Certain conditions increase the secretion of thyroid ho
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Thyroglobulin
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A large glycoprotein from which thyroid hormone is produced.
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Calcitonin
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Hormone released by the thyroid gland that promotes a decrease in calcium and phosphate levels of the blood, it’s synthesised in parafollicular cells located within the thyroid gland. This is achieved by inhibiting bone resorption(breakdown) and increasing the uptake of these minerals into the bone matrix.Calcitonin works closely with parathyroid hormone PTH in maintaining the homeostatis of blood calcium concentrations. The secretion of these hormones is controlled by the negative feedback systems. The actions of these two hormones oppose each other, so calcitonin reduces blood levels and parathyroid hormone increases blood calcium levels.
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Human growth hormone HGH
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Stimulates the secretion of insulin-like growth factors (IGF’s) from a number of locations. IGF’s promote the growth of body cells, protein synthesis, and tissue repair.
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Growth hormones
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HGH human growth hormone, the most abundant hormone released by the anterior pituitary gland.One stimulus for the secretion of GHRH growth hormone release hormone is hypoglycaemia, it is released from the hypothalamus, this then stimulates the release of hGH human growth hormone from the anterior pituitary gland. hGH stimulates the liver, skeletal and other muscle cells to release insulin-like growth factors (IGF’s). IGF’s stimulate cells to synthesise proteins, break down fats for energy production and decrease cell’s dependency on glucose for energy, thus glucose may be utilised by neurons instead. These effects explain why some refer to hGH as the anti-anging hormone. Hyperglycemia and obesity can have the opposite effect, when blood sugar levels are higher the hypothalamus releases HGIH hormone growth inhibitor hormone, stopping further release of hGH from the pituitary.
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Thyroid hormone
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(TH) Regulates many metabolic functions, is essential for growth, essential for development of the nervous system, essential for nervous system functioning in adults, amplifies the activity of the sympathetic nervous system
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Sympathetic nervous system
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The division of the autonomic nervous system that activates the body to cope with some stressor (danger, excitement, etc); the fight, fright and flight subdivision; increases rate and force of heartbeat.
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Parathyroid glands
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Small endocrine glands, commonly four, located on the posterior surface of the lateral lobes of the thyroid gland. Their principle secretion is parathyroid hormone (PTH), also called parathormone. The main function of this hormone is to regulate the levels of calcium, magnesium and phosphate ions in the bloods. This is done by a) increasing the number and activity of osteoclasts, which increases bone resorption and the release of calcium and phosphates into the blood b) acting on the kidneys to reduce calcium and magnesium excretion and increase the excretion of phosphates in the urine c) acting on the kidneys to increase the formation of the hormone calcitriol(active form of vitamin d), which increases the absorption of calcium and magnesium from the gastrointestinal tract. All of these actions increase the concentration of calcium in the bloodstream.
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SEX HORMONE PRODUCTION
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One of the hypothalamic hormones in GnRH, the frequency and amplitude of GnRH secretion stimulates the production of FSH and LH by the anterior pituitary gland. FSH and LH act on the testes in men and ovaries in women, leading to further production of hormones by those organs. FSH in males promotes the production of sperm, in females promotes the development of oocytes and stimulates the ovaries to produce oestrogen. LH in males timulates the testes to produce testosterone, in females it triggers ovulation as well as ovarian production of oestrogen and progesterone and the formation of the corpus luteum.
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Parathyroid hormone
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(PTH) Chief cells are the source of this peptide hormone released by the parathyroid glands that regulate blood calcium levels. Declining blood calcium levels cause the parathyroid glands to secrete PTH, the primary regulator of blood calcium levels. 1) PTH acts directly on the kidney to increase resorption of calcium. 2) PTH increases resorption of bone. This increases blood calcium levels. 3) PTH promotes the final conversion of vitamin D to its active form, the steroid hormone, calcitriol, that increases uptake of calcium from the intestine.
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Calcitriol
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The active form of vitamin D which promotes calcium, magnesium and phosphate levels of the blood by inhibiting bone breakdown and accelerating calcium absorption by bone.
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Steroid hormone
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Flat molecules made of four interlocking carbon rings; they are fat soluble and contain little oxygen
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Thymus
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Endocrine gland located deep in the sternum, and between the lungs in the thorax. Involved in the functioning of the immune system. Secretes a family of peptide hormones that includes thymosin and thymopoietin. Large at birth and increases in size until puberty when it gradually atrophies and is replaced by adipose and fibrous tissues in adults. The most important hormone secreted is thymosin, this hormone promotes the proliferation and maturation of T-cels, a type of immune cell.
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Thymosin
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Hormone made in thymus gland that promotes lymphocyte formation (t-cells)
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Thymopoietin
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Hormone made in thymus gland that promotes lymphocyte formation.
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T-cell development
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Thyroid hormones regulate their development and play a role in immune response
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Adrenal gland
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Paired endocrine glands, triangular in shape,located on top of each kidney; each consists of an outer region called the adrenal cortex and a small central/inner region called the adrenal medulla. Cortex secretes hormones called mineralocorticoids, glucocorticoids, and androgens. Medulla secretes adrenalin(epinephrine) and noradrenalin(norepinephrine)
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Mineralocorticoids
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The main mineralcorticoid secreted by the adrenal cortex is aldosterone. This hormone acts of the kidneys and helps regulate water and mineral balance in the body. Aldosterone is therefore involved in mineral homeostatis. Aldosterone increase the retention of sodium at the kidneys, which leads ti the retention of water. As a result aldosterone is involved in the regulation of blood volume and pressure.
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Androgen
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Hormone with testosterone-like actions.
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Adrenal medulla
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The inner portion of the adrenal gland that produces two principle hormones (also neurotransmitters): Adrenaline(epinephrine) and noradrenaline(norepinephrine). Both of these hormones produce effects that enhance those of the sympathetic division of the ANS. These two hormones assist with the fight-or-flight stage of stress response by –increasing heart rate-increasing cardiac output and blood pressure-increasing blood flow to the heart, liver, skeletal muscles and adipose tissue-dilating airways to the lungs-Increasing blood levels of glucose and fatty acids-Dilating blood vessels of the heart, lungs, brain and skeletal muscles-constricting the blood vessels to the skin and the digestive system, diverting blood from these regions to the muscles and the brain-reducing digestive activities-Increasing the activity of sweat glands. Released as neurotransmitters they provide an immediate response, but continue to stimulate organs as they circulate in the blood as hormones.
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Catecholamines
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A type of organic compound that contains a benzene ring structure and an amino group, like dopamine, epinephrine and norepinephrine. Epinephrine is 4-5 times more abundant than NE. Important in the fight or flight response.
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Zona glomerulosa
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Outer zone of the adrenal cortex that synthesized mineralocorticoids that affect salt balance. Aldosterone is the most important. Among its function are sodium retention and potassium excretion by the kidneys
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Zona fasciculate
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Middle zone of the adrenal cortex that synthesized glucorcorticoids and androgens
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Zona reticularis
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Inner zone of adrenal cortex that synthesized glucocorticoids and androgens
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Glucocorticoids
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The main glucocorticoid is cortisol, other are corticosterone and cortisone. Cortisol is our main stress hormone, released in times of need. It has powerful anti-inflammatory effects, raises blood sugar levels, stimulates the breakdown of fat for energy production and also raises blood pressure. Other effects include catabolism of protein and suppressing the immune response.Negative feedback controls cortisol production, low levels of glucocorticoids stimulates the hypothalamus to release CRH, which then stimulates the anterior pituitary production of ACTH, which in turn triggers glucocorticoid production by the adrenal cortex. Prolonged secretion of CRH can also stimulate release of MSH from the anterior pituitary.
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Androgens
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Small amounts of weak androgens are secreted by the adrenal cortex in both males and females. The main androgen secreted by the adrenal cortex is dehydroepiandosterone DHEA. Androgens help control the development of the secondary sex characteristics, and function of the reproductive organs in both males and females. However in adult males the androgen testosterone (from the testes) dominates and the effect of the adrenal androgens is small. In women adrenal androgens help to promote libido and are converted to oestrogens by other tissues in the body. In this way adrenal androgens contribute to the total amount of oestrogens present in the body, and are perhaps the most important after menopause. Adrenal androgens contribute to growth and the development of the auxillary and pubic hair during puberty in both males and females.
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Pancreas
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Gland located behind the stomach, between the spleen and duodenum, produces both endocrine and exocrine secretions. Exocrine function- 99% of the cells of the pancreas have an endocrine function. They’re arranged into clusters called acini and secrete digestive enzymes into the small intestine. Necessary for chemical digestion. Endocrine function-The remaining cells are scattered between the acini in pancreatic islets (Islets of langerhams). These are endocrine cells and secrete hormones. Depending on the hormone that they secrete they will be called alpha, beta, delta of F cells.The main hormones secreted by the pancreas are Insulin and Glucagon.
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Acinar cells
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Pancreatic cell that produces enzyme-rich juice, and exocrine. Produce Pancreatic islets known as the Islets of Langerhans; irregular microscopic structures scattered throughout the pancreas, composed of alpha cells, beta cells, delta cells and F cells.
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Somatostatin
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(SST) Hypothalmic hormone that inhibits secretion of growth hormones, function not well known in humans
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Insulin
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Lowers blood glucose levels, by stimulating the uptake of glucose into the cells. Once inside a cell it may be used to produce energy, stored as glycogen in the liver and muscle cells or fat in adipocytes. It also stimulates protein synthesis. Insulin is secreted when stimulated by elevated blood sugar concentrations, thus released in higher amounts after meals.
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Triglycerides
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Fats and oils composed of fatty acids and glycerol, the bodys most concentrated source of energy fuel, also known as neutral fats
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Glycogen
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A polysaccharine composed of glycogen subunits found primarily in the muscle and liver cells of animals
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Glucose
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Often called blood sugar, the principle sugar in blood.
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Glucagon
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Increases the blood glucose concentrations, by stimulating the liver to manufacture glucose and release it into the blood. The secretion of glucagon is stimulated by low blood sugar levels, and as a result is secreted inbetween meals when blood glucose levels fall.
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Glucagon-function
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Low blood glucose(hypogylcemia) stimulates alpha cells to secrete glucagon. It acts on the hepatocytes(liver cells) to convert glycogen into glucose from lactic acid and certain amino acids(gluconeogenesis). Glucose released by hepatocytes raises blood glucose level to normal. If blood glucose continues to rise, hyperglycemia inhibits release of glucagon.
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Insulin-function
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High blood glucose(hyperglycemia)stimulates beta cells to secrete.The insulin then acts on various body cells to –Accelerate facilitated diffusion of glucose into cells –speed conversion of glucose into glycogen –Increase uptake of amino acids and increase protein synthesis –Speed synthesis of fatty acids –Slow glycogenolysis –slow gluconeogenesis. Blood glucose levels then fall, and if they continue to fall hypoglycaemia stops the release of insulin.
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Ovaries
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Paired endocrine glands located in the female pelvic cavity. They produce the following hormones: Oestrogen and progesterone-both of which are involved with the development and maintenance of secondary sex characteristics in the female. They also work closely with the anterior pituitary hormones FSH and LH to regulate the menstrual cycle, maintain pregnancy and prepare the mammary glands for lactation.Inhibin-Inhibits FSH secretion from the anterior pituitary. Relaxin-A hormone produced during pregnancy, it increases the flexibility of the pubic symphysis and helps to dilate the cervix during labour and delivery. Both of these actions make the movement of the baby through the birth canal easier.
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Granulosa cells
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Cells of the ovarian follicle that secrete estrogen
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Corpus luteum
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Ovarian structure that produces estrogen and progesterone after ovulation, major source of progesterone
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Theca cells
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Layer of cells in the follicle that secrete steroid hormones, just prior to ovulation small amounts of progesterone are produced by this and granulose
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Ovarian hormones
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Estrogen and progesterone together regulate ovarian function, cyclic changes in the uterine lining, and breast development during puberty. Estrogen promotes development of the female gamete (egg), development of the secondary sex characteristics, and maturation of the reproductive organs in females. Progesterone is required for pregnancy. Inhibin suppresses secretion of FSH.
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Testes
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Paired endocrine glands located in males, in a sac called a scrotum outside the abdominopelvic cavity. They produce the male gametes and secrete the steroid testosterone and the peptide inhibin. Testosterone is the main androgen, it regulates sperm production, stimulates the development of the secondary male sex characteristics. Inhibin-inhibits the secretion of FSH from the anterior pituitary.
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Interstitial cells
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Cells of the testes that secrete testosterone
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Sustentacular cells
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Cells of the testes that support sperm production, form inhibin, which also suppresses FSH
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Seminiferous tubule
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Highly convoluted tubes within the testes, site of sperm formation
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Testosterone
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Promotes development of the male gamete (the sperm); development, maturation and maintenance of the male reproductive organs, development of secondary sex characteristics, and sex drive
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Endocrine Tissues
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Hormones produced in endocrine cells located in organs that have non-endocrine functions. They include the brain, heart, kidney and gastrointestinal tract
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Posterior lobe of pituitary gland-posterior pituitary
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The posterior pituitary DOESN’T synthesis hormones, instead it stores and releases two hormones that are manufactures in the hypothalamus. These are ADH- anti-diruetic hormone and oxytocin OT
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Anti-diruetic hormone ADH
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This hormone increases the reabsorption of water in the renal tubules of the kidneys. This conserves water and decreases urine volume. Also raises blood pressure and decreases water lost through perspiration.
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Oxytocin OT
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Stimulates the contraction of smooth muscle in the uterus during childbirth, and stimulates milk ejection from the mammary glands.
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Thyrotropin-releasing hormone
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(TRH) stimulates secretion of TSH (TSH acts on the thyroid gland to stimulate secrete of thyroid hormones)
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Gonaditropin-releasing hormone
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(GnRH) stimulates secretion of FSH and LH in adults of both sexes (these stimulate maturation of gametes and production of reproductive hormones)
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Corticotropin-releasing hormones
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(CRH) stimulates secretion of ACTH, which stimulates secretion of glutocorticoids and other hormones of the adrenal cortex
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Growth hormone releasing hormone
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(GHRH)- stimulates secretion of growth hormone, which stimulates growth energy and metabolism
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Somatostatin
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Secreted by the pancreas (SST)inhibits secretion of both insulin and glucagons. It’s identical to another hormone that is roduced by the hypothalamus called growth hormone inhibiting hormone(GHIH)
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Pancreatic polypeptide
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Stops the secretion of somatostatin
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Dopamine
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Prolactin inhibiting hormone (PIH), a chatecholamine that regulates the secretion of prolactin
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Prolactin releasing factors
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(PRF)-causes secretion of prolactin, TRH may be one. Prolactin is different from the other anterior pituitary hormones because it is normally inhibited by the hypothalamus.
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Atrial natriuretic peptide
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ANP secreted by the heart, causes the kidneys to increase excretion of sodium. Participates in control of slat balance and contributes to control of blood volume and blood pressure
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Gastrin
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secreted by the stomach, stimulates HCl secretion and growth of the gastric mucosa, produced by G cells in the pyloric antrum of the stomach.
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Erythropoietin
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peptide hormone produced by the kidney that stimulates bone marrow to increase production of red blood cells
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Calcitriol
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Steroid hormone that is an active form of Vitamin D, which promotes absorption of dietary calcium in the small intestine, and the parathyroid hormone promotes the final conversion of Vitamin D to this active form
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Duodenum
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First part of the small intestine
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Jejunum
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part of the small intestine between the duodenum and the ileum
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Cholecystokinin
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(CCK) is an intestinal hormone that stimulates gallbladder contraction and pancreatic juice release, produced by I cells, causes gall bladder to contract, thereby moving bile into the small intestine, it causes the exocrine pancreas to produce digestive enzymes that move into the small intestine, it causes growth of the exocrine pancreas and mucosa of the gall bladder
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Secretin
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an intestinal hormone that stimulates bicarbonate secretion by liver and pancreas that moves into the small intestine, produced by S cells, and since bicarbonate neutralizes the acidic chime that comes from the stomach, its natures antacid, also stimulates growth of the exocrine pancreas
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Motilin
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an intestinal hormone that stimulates the migrating (motor) motility complex in the small intestine, is released about every 90 minutes during times of fasting. Stimulated production of a migrating peristaltic contraction, called migrating motility complex that acts to sweep the contents of the small intestine toward the terminal ileum.
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Glucose-dependent insulinotropic peptide
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(GIP)In the presence of glucose, GI hormone causes feed forward release of insulin
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