The flashcards below were created by user
Dthiery237
on FreezingBlue Flashcards.
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angeion
vessel;angiotension
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corpus
body;corpus luteum
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diabeties
to pass through; diabeties
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diourein
to urinate;diuresis
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erthros
red; erythropoietin
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infundibulum
funnel;infundibelum
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insipidus
tasteless; diabetes insipidus
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krinein
to secrete; endocrine
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mellitum
honey;diabetes mellitus
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natrium
sodium; natriuretic
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ouresis
making water;polyuria
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poiesis
making;erthropoietin
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synergia
working together;synergistic
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teinein
to stretch; angiotensin
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thyreos
an oblong shield; thyroid
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tokos
childbirth;oxytocin
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tropos
turning;gonadotropins
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Objective:
Compare the similarities between the endocrine and nervous system(pp.367-368)
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Cellular communication over great distances is coordinated by the
Nervous and endocrine system
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Long term cellular communication is provided by
the Endocrine system
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The endocrine system uses hormones to
- relay information and instructions between cells.
- each hormone has specific target cells that will respond in its presence
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Similarities of endocrine and nervous system
- Both rely on release of chemicals that bind to specific receptors on target cells
- both share various chemical messengers
- Both are primaraily regulated by negative feedback and control mechanisms
- both coordinate and regulate the activites of other cells,tissues,organs, and systems and maintain homeostasis
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Objective:
Compare the major chemical classes of hormones (pp.368-369)
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Cytokines
- (Local hormones)
- Chemicals released by endocrine cells that may affect adjacent cells only
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Hormones
Chemical messengers that are released in one tissue and transported by the bloodstream to reach cells in other tissues
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Three structural groups of hormones
- Amino Acid Derivatives
- Peptide hormones
- Lipid derivatives
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Amino acid derivatives
- Small molecules structurally similar to amino acids
- Epi, NE, Thyroid hormones, melatonin
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Peptide hormones
- consist of chains of amino acids
- range from
- ADH to oxytocin, to small proteins such as growth hormone and prolactin.
- largest class of hormones
- all hormones secreted by the hypothalamus, pituitary gland,heart,kidneys,thymus,digestive tract, and pancreas
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Lipid based hormones
Steroid hormones and eicosanoids
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Steroid hormones
- lipids that are derived from(also structurally similar to) cholesterol
- released by reproductive organs and adrenal glands, insoluable in water
- bound to specific transport proteins in the blood
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Eicosanoids
- fatty acid based compounds derived from 20 carbon fatty acid Arachidonic acid
- include
- prostaglandins, that coordinate local cellular activites and affect enzymatic processes in extracellular fluids, including blood clotting
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Objective:
Explain the general mechanisms of hormonal action (pp.369-372)
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Structural proteins determine general shape and interal structure, enzymes direct cells metabolism and Hormones alter cellular operations by...
changing the identies, activityes, locations, or quantities of important enzymes and sutrcutral proteins in varous target cells
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Target cells sensiitity is determinded by the presence or absence of
a specific recprot which a given hormone reacts
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Hormone receptors are located
either on the cell memrbrane or inside the cell
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Cell membrane receptors are for
Cells that are not lipid soluable
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Hormones that bind to the cell membrane receptors do not
have direct effects on the target cells
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When bound to cell membrane receptors they are considered
First messengers that trigger the appearance of a second messenger in the cytoplasm
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G protein
- is the link between first messenger and the second messenger
- is an enzyme complex that is coupled to a membrane receptor
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Second messenger may function as an
enzyme activator or inhibitor, but the net result is change in cells metabolic activites
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Most important second messenger is
cAMP (cyclicamp)
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cAMP apperance depends on G protein which activates
adenylate cyclase
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adenlyte cyclase converts ATP
to a ring shaped molecule of cAMP
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cAMP activates
kinase enzymes which attach a high energy phosphate group to another milecule in a process called phosphorylation
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Phosphorlyation of a membrane proteins can
open ion channels, and in the cytoplasm many enzymes can only be activated by it
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Effects of cAMP are short lived and is broken down by
(PDE) phosphodiesterase
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In few instances activation of the G protein can lower conentration of cAKP by stimulating PDE
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Important second messengers are
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Steroid hormones diffuse
rafpidly through the lipid protion of the cell membrane and bind to receptors in the cytoplasm or nucleus
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Hormone receptor complex then activates or inactivates
specific genes in the nucleus
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Steriod hormones can
alter the rate of mRNA transcription thereby changing the structure or function of the cell
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Thyroid hormones cross the cell membrane by
either diffusion of transport mechanism
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once inside the cell thyroid hormones bind to receptors within....
the nucleus or on mitochondria
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thyroid hormones inside the nucleus
- activate specific genes or change the rate of mRNA transcription.
- resulting in an increase in metabolic activity due to changes in number of enzymes in cytoplasm
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thyroid hormones bound to mitochondria...
increase the mitochondrial rates of ATP production
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hormone release occurs where
cappilaries are abundent and quickly enter the blood stream
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In the blood steam hormones may
circulate freely or attach to special transport proteins
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Freely circulating hormones remain functional for less then
one hour sometimes as little as two minutes
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Free hormones are inactivated when
- they diffuse out of the bloodstream and bind to receptors on target cells
- they are absorbed and broken down by certain liver or kidney cells
- they care broken down by enzymes in plasma or interstitial fluids
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Steroid and thyroid hormones remain in ciruclation much longer because
almost all become attached to special tranport proteins
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as free hormones are removed they are replaced by
the release of bound hormones
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Objective:
Describe how endocrine organs are controlled (pp.372-373)
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Stimuli that control endocrine activity
- Humoral stimuli
- Hormonal Stimuli
- Neural stimulation
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Humoral stimuli
Changes in composition of extracellular fluid
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Hormonal stimulatuon
changes in levels of circulating hormones
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Neural stimulation
arrival of neurotransmitter and a neuroglandular junction
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Hypothalamus provides the
highest level of endocrine control by acting as an important link between nervous and endocrine systmes
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Hypothalamus regulates the activities of the nervous system and endocrine system:
- hypothalamus secretes regulatory hormones that control the cells in the anterior pituitary gland. RH, and IH released by anterior pituitary gland
- Hypothalamus acts as an endocrine organ by synthesizing tow hormones, ADH, oxytocin,
- released by the posterior pituitary gland
- contains the ANS centers that control the endocrine cells of the adrenal medullae through sympathetic innetvation
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RH
Releasing hormones stiumlate the production of one or more hormones in the anterior pituitary
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IH
Inhibiting hormones prevent the synthesis and secretion of pituitary hormones
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Objective:
Discuss the location,hormones, and functions of the following endocrine glands and tissues: pituitary gland,thyroid gland,parathyroid glands,adrenal glands,pineal gland,pancreas,kidneys,heart,thymus gland,testes, ovaries, and adipose tissue (pp.373-396)
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Pituitary gland (hypophysis)
- Secretes nine different hormones.
- All are peptides or small protiens that bind to membrane receptors,
- all use cAMP as a second messenger
- is small,oval shaped gland nestled within the sella turicina (depression in the sphenoid bone of the skull)
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Pituitary gland hangs beneath the hypothalamus connected by a slender stalk called
the infundiubulum
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Structure of the pituitary gland includes
distinct anterior and posterior regions
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Anterior pituitary gland contains endocrine cells surrounded by
an extensive capillary network
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The capillary network provides entry into the circulatory system for
hormones secreted by the endocrine cells of the anterior pituitary gland, is part of the hypophyseal portal system
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Before leaving the hypothalmus, the cappillary netowkr unties to from a series of slightly larger vells that descent to the anterior pituitary before forming a
second capillary network
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Blood flows from
one capillary bed to an other
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Blood vessels that link two capillary networks, including the vessels between the hypothalamus and anterior pituitary are called
portal vessels, in this case they have the structure of veins
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The entire complex is called the
portal system
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Portal systems ensure that all of the blood enters the protal vessels reaches
certain target cells before returning to the gneral circulation.
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portal systems are named after
their destinations
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An endocrine cell in the anterior pituitary mayb be controlled by
releasing RH,IH, or combo of both
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The regulatory hormones secreted at the hypothalamus are transported directly to the anterior pituitary by the hypopopseal portal system
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Rate of regulatory secretion by the hypothalamus is regulated through
negative feedback mechanisms
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Many regulatory hormones are called
tropic hormones because they turn on other endocrine glands or support the functions of other organs
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Anterior pituitary gland produces 7 hormones
- Thyroid stimulating hormone (TSH)
- Adrencorticoidtropic hormone (ACTH)
- Follicle stimulating hormonre (FSH)
- Luteinizing hormone (LH)
- Prolactin (PRL)
- Growth hormone (GH)
- Melanocyte stimulating hormone(MSH)
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4 Hormones regulate the production of hormones by other endocrine glands
- Thyroid stimulating hormone (TSH)
- Adrencorticotropic hormone (ACTH)
- Follicle stimulating hormone(FSH)
- Luteinizing hormone (LH)
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Thyroid Stimulating Hormone (TSH)
- AKA throtropin
- targets the thyroid gland and triggers release of thyroid hormones
- TSH is released in response to thyrotropin releasing hormone (TRH) from the hypothalamus
- as concetraions of thyroid hormoens rise, rates of TRH and TSH production decline
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Adrencorticotropic hormone (ACTH)
- stimulates relase of steroid hormones by the adrenal cortex
- ACTH specifically tragets cells that produce hormones called glucocorticoids(affect glucose metabolism)
- ACTH release occurs under stimulaton of CRH (corticotropin releasing hormone) from the hypothalamus.
- Negative feedback similar to TSH
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Gonadotropins
- group of hormones that regulates the activities of male and female organs (gonads)
- production stimulated by gonadotropin releasing hormone (GnRH)
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Pituitary gland produces two gonadotropins
FSH, LH
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Follicle stimulating hormone (FSH)
- promotes follicle (and egg) develpoment in females and stimulates secretion of estrogens(steroid hormone produced by ovarian cells)
- In males
- FSH supports sperm production in testes
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Inhibin
is released by the cells of the testes and ovaries inhibits the relase of FSH and GnRH torugh negative feedback comparable to TSH
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Luteinizing Hormone (LH)
- induces ovulation
- promotes secretion by ovaries and estrogens and progestins when prepare the body for possible pregnancy
- in males it is sometimes called ICSH interstitial cell stimulating hormone
- stimulates intersitial cells of the testes to produce sex hormines
- negative feedback simular to TSH
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Male sex hormones are called
- androgens
- most important testerone
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Prolactin (PRL)
- works with other hormones to stimulate mamary gland development. In pregnancy and period of nursing following delivery
- PRL effects on males is poorly understood
- may help regulate androgen production
- Regulation of PRL release involves PRF (PRL releasing)and PIH(PRL inhibiting) from the hypothalamus
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Growth hormone (GH)
- Human growth hormone (hGH) or Somatropin
- stimulates cell growth and replicaiton by accelerating rate of protein synthesis
- Skeletal muscle and cartilage cells are sensitive
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Stimulation of GH involves two mechanisms:
- Indirect,the primary
- Direct
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indirect
- liver cells respond to the presence of GH by synthesing Somatomedins or insuling like grotwh factors(IGFS) -pepide hormones
- increase the rate that amino acids are taken up and incorperated into protiens
- best after meals
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Direct
- occurs after glucose and amino acid conctrations return to normal levels
- epitheila and connective tisssue,GH stimulates stem cell divisions
- in adipose it stimulates breakdown of stored fats and releases fatty acids into blood
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Glucose sparing effects
many tissues stop breaking down glucose and start breaking down fatty acids to generate ATP
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GHGH and GHIH are from
- hypothalamus
- mateomedins stimulate GHIH and inhibit GHRH
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Melanocyte stimulating hormone (MSH)
stimulates melanocytes in the skin and increases production of melain
- MSH in human pituitary is secreted
- during fetal development
- in very young children
- pregant women
- in some diseases
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Posterior pituitary gland contains axons from two different group of neurons located in
the hypothalamus
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The two groups seperately produce
- ADH and oxytocin
- these products are transported within axons along the infunibulum to the posterior pituitary
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ADH
- Anti diuretic hormone
- primary function is to decrese the amount of water lost in the urine
- caused by rise in concentraion of electroltes in blood , fall in blood volume or pressure
- adh is inhibited by alchahol
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Oxytocin
stimulates smooth muscle contrations of the uterous during labor and elivery and contractile cells in the mamary glands
In both sexes during sexual stimulation and peak at orgasm contractions in mammary glands/ uterous and prostate gland(males)
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Thyroid gland is anatomically located
Anterior to the trachea and inferior to the thyroid cartilage
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The two lobes of the thyroid gland are united by a slender connection called the
isthmus
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Hormone that activates the thyroid gland is
TSH from the anterior pituitary gland
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Thyroid gland contains numerous thyroid follicles which are
- spheres lined by a simple cubodial epithelium
- the cavity in each follicle contains large amounts of suspended proteins and thyroid hormones.
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A network of _____ surround each follicle
Capillaries
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Thyroid hormones are manufactured by the
Follicular epithelial cells
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Almost all of the released thyroid hormones are unavaiable becuase they attache to
plasma proteins in the blood stream
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The unbound hormones are free to diffuse into target cells, when levels of the unbound hormone decrease
the plasma proteins release additional hormone
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The blood steam contains
more then a weeks worth of thyroid hormones
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Thyroxine
- accounts for 90% of all thyroid secretions
- contains 4 atoms of iodine
- tetraiodothronine T4
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Trioodothyronine T3
is related but more potent molecule that contains 3 iodine atoms
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Thyroid hormones readily cross
the cell membrane
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When inside the cell they bind to
receptor sites on the mitochondria and in the nucleus
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Binding of thyroid hormones to mitochondira
increases the rate of ATP production
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Thyroid hormone binding to the nucleus
- activate gene coding for the synthesis of enzymes involed in glyolysis and energu production
- increaed in cellular rates of metabolism and oxygen consumption
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Calorigenic effect of thyroid hormones
the cell consumes more energy, and use of energy is measured in calories
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Normal production of thyroid gormones establishes the background
rates of cellular metabolism
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Overproduction or underproduction of thyroid hormones can cause
serious metabolic problems
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inadequate dietary iodine intake leads to an inability to
synthesise thyroid hormones
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Lack of iodine causes thyroid follicels to become distend, the result is called
Goiters
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C cells
- Parafollicular cells
- endocrine cells sandwiched between the follicle cells and their basment membranes
- produce calcitronin (CT) helps regulate calcium ion concentrations in fluids
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Calcitronin secretion is
independent of hypothalamus or pituitary gland
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CT is released when calcium ions rise in the blood
rise above normal limits
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CT
inhibits osteoclasts which slows the relase of calcium from the bone and stimulates calcium excretion at the kidneys
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Important functions of CT
- stimulates active bone growth and calcium depostiation in skeleton in childhood
- resdues loss of bone mass in prolonged starvation
- during late pregnancy, when the maternal skeleton competes with the developing fetus for absorbed calcium ions
- unclear in healthy nonpregnant adults
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Two parathryoid glands are embedded in the
posterior surfaces of the thyroid gland
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Chief ceklls
- produce parathyroid hormone
- the function of the other cell type are unknown
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Chief cells monitor
Concentraition of circulating calcium ions
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When calcium ion levels fall below normal cheif cells secrete
PTH parathyroid hormone
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PTH
- stimulates osteoclasts
- inhibits bone building functions of osteoblasts
- reduces urinary excretion of calcium ions
- stimulates kidney to form and secrete calcitrol
- which promosts absorption of CA+ and PO4 by the digestive tract
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Adrenal gland
- a yellow pyramid shaped gland,
- suprarenal
- sits on superior border of each kidney
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Each adrenal gland has two parts
an outer adrenal cortex and inner adrenal medulla
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Yellow color of the adrenal cortex is due to
presence of stored lipids
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The adrenal cortex produces
more then two dozen steoid hormones , collectively called adrencoricoid steroids or corticosteroids
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Corticosteroids are bound to
transport proteins
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Adrenal cortex contains three distinct regions or zones caled the
- outer zone (produces mineralcorticoids)
- Middle produces (glucocorticoids)
- Inner(Androgens)
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Mineralcorticoids (MCS)
affect the electrolyte composition of the body fluids
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Aldosterone
- Principle MC
- Stimulates the conservation of sodium ions and conservation of potassium ions by targeting cells that regulate ionic composition of excreted fluids
- salt receptors in tongue
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Aldosterone causes renention of sodum by preventing the loss of sodium ions in
urine, saliva, and digestive seretions
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Retention of sodium ions is paired with a loss of
potassium ions
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Reabsorption of sodium ions results in
osmotic reabsorption of water at the kidneys,sweat glandsmsalivary glands and pancreas.
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Aldosterone secretion occurs in response to
- a drop in blood sodium content
- blood volume/blood pressure
- or a rise in potassium levels
- also in response to hormone angiotension II
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Glucocorticoids (GCS)
- affect glucose metabolism
- cortisol
- corticosterone
- cortisone
- are most important glucocorticoids
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Glucocorticoid secretion occurs uner ACTH stimulation and is regulated by
negative feedback
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GCS hormones accelerate
the rates of glucose synthesis and glycogen formation especially in the liver
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Adipose tissue and other tissues responds to GCS by
- breaking down fatty acids instead of glucose
- glucose spating effect results increase of BGL
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GCS also have what characteristic
- Antiinflammatory
- may be used to control severe allergic reactions
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Adrogens
- Both sexes produce adrogens
- once in blood stream adrogens are converted to estrogen
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Adrenal medulla
- reddish brown coloration due to many blood vessels within it
- Innervated by preganglionic sympathcic fibers
- secretory activites of the adrenal medullae are controlled by the sympathic division of the ANS
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Adrenal medulla contains two populations of secretory cells
- one that produces epi (E)
- other produces Norepi (NE)
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these hormones are released at a low rate but sympathetic stimulation
accelerates rate of discharge dramatically
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Epi makes up
- 70-80% of secretions
- the rest is NE
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Adrenal medulla secretions secretions trigger
- motabolization of glycogen reserves and accelerate the breakdown of glucose to provide ATP
- result in increased muscular power and endurance
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In adipose tissue
- stored fats are broken down to fatty acids and in the liver glycogen molecules are converted to glucose
- then released into circulation
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metabolic changes that follow E and NE release peak
at 30 seconds and linger for several mins therafter
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Hyperadrenalism
- cushings syndrome
- treated with GCS
- moon faced, weight gain in trunk,face,and trunk
- tendency to bruise
- mood swings
- facial hair in women
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Adrenal Insufficency
- addisons disease
- due to cortical distrucion
- TB one of leading causes
- 90% due to autoammune
- progeseeive weakness,fatique, decreaed appitite, and weight loss
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Pineal gland
- lies in the poserior portion of the roof of the third ventricle
- synthesizes melationin
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Melationin functions
- inhibition of reporductive function
- axtioxidant actiity
- establishment of day night cycles
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the pancreas lies
in the j shaped loop between the stomach and proximal protion of the small intestine
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Pancreas
contains endocrine and exocrine cells
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Pancreas primarily is a
digestive organ whose exocrine cells make digestive enzymes
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Endocrine cells of the pancreas produce two hormones
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cells of the endocrine pancreas from clusters known as
pancreatic islets or the islets of langerhans
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the islets are scattered
among the exorine cells and account for 1% of all pancreatic cells
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Each islet contains several types of cells
the two most important are
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Alpha cells produce
glucagon
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Beta cells secrete
insulin
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Glucagon and insulin regulate
BGL
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BGL rises above normal homeostatic level then
beta cells release insulin
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All cell membranes contain insulin recpetors except
- neurons and RBC, which cannot metabolise nutrients other then glucose
- epithelial cells of the kidney tubules where glucose is absorbed
- epithelial cells of the intestinal lining ,where it is obtained from diet
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When glucose is abundent
all cells use it as an energy source and stop breaking down lipids and amino acids
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ATP genertated by the breakdown of glucose molecues is used to build
proteins and increase energy reserves
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Most cells increase
- their rates of protein synthesis in respone to insulin
- and increase the rate of amino acid transport across cell membranes
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Insulin stimulates fat cells to increase
their rates of tiglyceride synthesis and storage
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In liver and skeletal muscle fibers
insulin excelerates the formation of glycogen
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When glucose is abundent insulin stimulates
glucose ultization to support growth and establish glycogen and rat reserves
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low BGL
glucagon and energy reserves are mobilized
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Parasympathetic stimulation
enhances insulin release where as sympathitic stimulation inhibits
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Type I diabeties
Insulin dependent
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Diabetic emergencys
- hypoglycemia
- keoacidosis
- nonketotic hyperosmolar coma
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DKA
- dehydration
- kussmal respirations
- tachycardia
- general malaise
- warm/dry to touch
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NKHC
- higher mortalitity rate then DKA 40 -70%
- slower onset
- letheragy ,confusion, warm , dry, tachy, dehydrated
- orthostatic hypotension
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Calcitrol
- in response to presence of PTH
- D3 important
- stimulates absorption of calcium and phosphate ions across the intersinal lining of the digestive tract
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EPO
- released by kidneys inrespone to low oxygen levels in kidney tissue
- stimulates RBC production in bone marrow
- Increased number of RBC elevates blood volume
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Renin
- released in respone to decline in blood volume,blood pressure, or both.
- renin starts an enzymatic chain reaction known aas renin angiontension system which forms angiogension II
- angiotension II simulates production of aldosterone and ADH
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Stretch receptors, when streched excessively release
- ANP (atrial natriuretic peptide)
- opposes angiotension II
- promotes loss of sodium ions and water at the kidneys and inhibits renin release and secreaiton of ADH and aldosterone.
- = reducaiton of blood volume and pressure
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Thymus
- located in the mediastinum
- grows at child ages and dimineshed by age 50
- thymosions play key role in development and maintenice of normal immune system
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interesitial cells of the testies produce the steroid
androgens , testosorone most important
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Testosterone promotes
functional sperm, maintains the secretory glands of the male reproductive track, and determines facial hair and body fat.
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Testosterone also effects
metabolic processes in the body,stimulates muscle growth, and produces aggressive behavioral responses
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FSH stimulation secretes the hormone
inhibin ,inhibits secretion of FSH of the anterior pituitary.
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Female sex cells develop in sepecialized cells called
follicles, under stimualation of the FSH
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Follicle cells that surround the ova produce
estrogens
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Negative feedback mechanism comparable to males with hormnes
FSH and inhibin
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Corpus luteum
after ovulation has occurred, the follicular cells reorganize into this
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Cells of the corpis luteum then being to release a mixture of estrogens and progestins especially
progesterone, accererates the movement of fertilized egss along the urerine tubes and prepares the uterus for hte arrival of a developing embryo
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the production of adrogens,estrogen, and progestins is controlled by
regulatory hormones released by the anterior pituitary gland
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Adipose tissue produces two peptide hormones
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Leptin
- is secreted throughout the body
- negative feedback control of appetite
- when you eat adipose absorbs glucose, and lipids and synthethizes triglycerides for storage, same time it releases leptin.
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leptin binds to neurons in the
hypothalams involved with emotion and appetite control. snese of satiation and supression of appetite
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Leptin enhances GnRH and gonadoropin synthesis. this explains why...
- thin girls enter puberty late
- increase in body fat content can improve fertility
- women stop menstrating when their body fat becomes low
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Resistin
reduces insulin sensitivity throughout the body, is poropased as missing link between obesity and type II diabeties mellitus
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Objective:
Explain how hormones interact to produce coordiated physiological responses (pp.396)
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When a cell recieves instructions from more then two different hormones at the same time, four ourcomes are possible
- Antagonistic
- Synergistic
- Permissive
- Integrative
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Antagonistic
Opposing effects
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Synergistic
additive effects , which produce a net result greater then if they would produce alone
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Permissive
One hormone must be present if a second hormone is to produce its effects
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integrative
produce different, but complementary results
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Objective:
Identify the hormones that are especially important to normal growth and discuss their roles.(pp.396-397)
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Normal growth requires cooperation of 6 hormones
- Growth hormone (GH)
- Thyroid hormones
- Insulin
- Parathyroid hormone (PTH)
- calcitrol
- reproductive hormones
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GH
- effects muscular and skeletal growth in children
- adults, maintains normal blood glucose concentrations and mobolizeslipid reserves stored in adipose tissue
- over/undersecretion causes dwarism/ giantism
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Thyroid hormoens
- If absent for first year after birth, nervous system will fail to develop normally and produce mental retardation.
- needed for normal skeletal development
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Insulin
needed for passage of supplies of energy and nutrients
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PTH/ calcitrol
promote absorption of calcium for building bone
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Reproductive hormones
activity of osteoblasts in key locations and growth of specific cell populations are affected by the presence or absence of sex hormones
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Objective:
Explain how the endocrine system responds to stress. (pp.397-398)
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Stress
physical or emotional condition thay threatens homeostatis
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Stressors may be
- Physical, illness or injury
- Emotional, depression or anxiety
- Enviromental, heat or cold
- metabolic, acute starvation
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General adaptation syndrome (GAS) (stress response) has three phases:
- Alarm
- Resistance
- Exhaustion
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Alarm phase
- Immediate response to the stress
- under direction of the sympathetic nervous system
- Energy reserves are mobilized and body prepares for any physical activies needed to eliminate or escape from the source of stress.
- EPI is dominant hormone of the alarm phase
- Produces fight or flight response
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Resistance phase
- If the adjustments of the alarm phase do not overcome the stess, resistance phase begins
- few hours, days even weeks.
- Glucocorticoids are dominant hormone of the resistance phase. Uses E, GH, and thyroid hormones. Energy demands are higher then normal due to the combined effects of these hormones
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The endocrine secretions of the resistance phase coordinate three intragated actions to maintain adequate levels of glucose in the blood
- 1.mobilization of lipid and protein reserves
- 2.the conservation of glucose for neural tissues
- 3.synthesis and release of glucose by the liver
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