Flashcards
BLOCK 8
Flashcards do conjunto (173)
- 1Actions of glucagon- Increase the breakdown of glycogen to glucose
- Increase breakdown of fats to fatty acids
- Increased synthesis and release of glucose - 2Actions of insulin- Increase glucose transport into cells
- Increase utilisation of glucose
- Increase glycogenolysis - 3What is diabetes insipidus?- Desensitisation to ADH in the kidneys --> leads to polyuria and polydipsia
- 4What is insulin resistance?More insulin is required for glucose to be taken up in to cells, so glucose stays in the bloodstream because the levels of insulin are not as high enough as they need to be for this to happen
- 5Complications of diabetes- Macrovascular - stroke, heart disease and foot disease
- Microvascular - renal disease and erectile dysfunction
- Neuropathies --> parathesia and postural hypotension - 6What are the actions of Somatostatin and where is it produced?- Produced in Delta cells of the endocrine pancreas
- Slows absorption of nutrients and inhibits glucagon and insulin secretion - 7What does pancreatic polypeptide do?- Inhibits the secretion of digestive enzymes, somatostatin and contraction of the gallbladder
- 8Exocrine What are acinus?- Berry shaped cluster of cells
- 9What are intercalated ducts?- Produce bicarbonate to neutralise acid secretions from stomach
- Lead to acinus to striated duct - 10What are striated ducts?Connects intercalated ducts to intralobular ducts
- 11Explain the stimulation of bicarbonate secretion from a pancreatic cellWater and carbon dioxide combine in pancreatic cell due to carbonic anhydrase to form H2CO3. This disassociates into H+ and HCO3-. HCO3- is exchanged to the small intestine lumen for Cl- cells. Cl- cells then move out and Na+ is exchanged for H+. Na+ then moves back out again and is exchanged for K+.
- 12What does CCK do and where is it produced?I cells of the SI
Promotes secretion of digestive enzymes and digests fats and proteins - 13What are the actions of secretin and where is it produced?S cells of the SI
- Acts on intercalated ducts and regulations secretions of the stomach and duodenum
- Acts via parasympathetic vagus nerve - 14What do episilon cells produce in the endocrine pnacreas?Ghrelin which increases hunger and acid secretion
- 15What are the two forms on insulin?Hexameric and monomeric
- 16Describe hexameric form of insulin- Inactive
- 6 molecules and a zinc molecule forming histidine bonds
- Low diffusion rate - 17Describe monomeric form of insulin- Active form
- Composed of alpha and beta chains linked via disulphide bridges
- High diffusion rate - 18How is insulin synthesised?Single polypeptide chain
Preproinsulin --> RER --> proinsulin --> golgi --> insulin packaged into granules - 19How is insulin secreted?- GLUT2 takes up excess glucose
- This causes an increase in ATP rise and glucokinase
- ATP rise depolarises beta cell and triggers insulin release
- Calcium influx and exocytosis of insulin granules - 20Outline the insulin receptor- Has alpha and beta chains
- Insulin binds to chains on alpha chains on external membrane. The beta chains have tyrosine kinase activity. - 21Mechanisms of insulin action- Triggers GLUT4 in muscles and adipose tissue to the cell surface to facilitate uptake of glucose into cells
- Acts to increase synthesis of glycogen
- Increases glucose transport - 22What enzyme forms the production of glycogen?Glucose phosphate enzyme
- 23How is glucagon generated?Proprotein convertase 2 cleaves proglucagon in alpha cells
- 24Name an incretin and its precursorGLP1 - Glucagon like peptide 1
Precursor is proglucagon - 25Actions of GLP-1- Reduces appetite
- Slows gastric emptying
- Reduces glycogenolysis
Stimulates insulin secretion - 26Actions of MetforminImproves insulin resistance in skeletal muscles and liver through cAMP mediated mechanism. Increases muscle glucose uptake but reduces breakdown of glycogen, gluconeogenesis and glucose release from cells
- 27Mechanism of sulfonyureas and examplesGliclazide and Glimepiride
- Works via K+/ATPase pump to cause influx of Ca2+ which in turn causes exocytosis of insulin vesicles leading to insulin release - 28How do thiazolidinediones work?- Agonists of the peroxisme proliferation activation receptor which modulates transcription of insulin sensitising genes
- 29How do glitazones work?- Insulin sensitiser in liver, skeletal muscle and adipose tissue
- 30Name and describe mechanism of GLP-1 analoguesExenatide and Liraglutide
- Increase insulin and peripheral glucose uptake and reduce glucagon and hepatic glucose output - 31Name and describe some DPP-4 inhibitors (the enzyme that degrades GLP-1)- Sitagliptin and Saxagliptin
- Prevent degradation of GLP-1 so lead to decrease in glucagon and increase in insulin - 32What are Gliflozins and name some examples?Dapaglifozin and Canaglifozin
- Inhibit the SGLT2 receptor in the kidney to prevent absorption of glucose, instead it is excreted out in the urine - 33Embryological origins of the anterior pituitaryOral ectoderm
- 34Embryological origins of the posterior lobeNeuroectoderm of the diencephalon
- 35Arterial supply of the pituitary glandSuperior and inferior hypophyseal arteries
- 36Venous drainage of the pituitary glandCavernous sinus
- 37Arterial supply of the thyroidSuperior and inferior thyroid arteries
- 38Venous drainage of the thyroid glandSuperior, middle and inferior thyroid veins
- 39What two types of cells is the thyroid gland made from?Follicular cells that contain secretory products and parafollicular cells that secrete calcitonin
- 40Arterial supply of the parathyroid glandsSuperior and inferior thyroid arteries
- 41What types of cell does the parathyroid gland have and what does it secrete?Chief/principal cells that secrete parathyroid hormone and oxytocin
- 42What is the function of the hypothalamus?Regulates limbic system
Hormone production
ANS regulation
Endocrine regulation - 43Role of the anterior pituitaryEndocrine gland that responds to signals from the hypothalamus to make and secrete hormones
- 44Role of the posterior pituitaryHormone filled vesicles are stored in posterior pituitary through neurons. They are released into the blood upon stimulation by ADH and oxytocin.
- 45Outline the HPA axis
- 46Some effects of having high cortisol levels in the blood- Protein depletion
- Hyperglycaemia
- Hyperlipidoedema
- Osteoporosis - 47Outline the hypothalamopituitary axis
- 48What is hypothyroidism?- Decreased levels of T3 and T4
- Leads to dry hair, puffy face, periorbital oedema and dry skin - 49What is hyperthyroidism?- High levels of T3 and T4
- Leads to increased weight loss/appetite, heat intolerance and irritability and tremor - 50What can be used to treat gigantism?Ocreotide inhibits GHRH mediated growth hormone release. Mimicks what somatostain would do naturally.
- 51What is ADH controlled by?Neurophysin which is a hormone in the posterior pituitary
- 52What can be used to treat Diabetes insipidus?Desmopressin which mimics vasopressin/ADH
- 53Where is oxytocin useful?Labour - stimulates contraction of the uterus. Released from posterior pituitary gland.
- 54What are thyroid hormones derived from?Iodinated tyrosine molecules
- 55What are the actions of thyroid hormones?- Stimulate metabolic rate
- Increase the size of mitochondria and Na+/K+ ATPase activity
- Increase heart rate and force of contraction
- Important in growth and development - 56Synthesis of thyroid hormones- Follicular cells
- Active transport of iodide ions across membrane into colloid
- Thyroid peroxidase changes iodide to iodine
- Iodine atoms attach themselves to tyrosine within thyroglobulin
- Peroxidase leads to joining of these atoms to form iodotyrosins that join to form T3 and T4 - 57Causes of hypothyroidism- Iodide deficiency
- Autoimmunity
- Tumours
- Congenital absence of thyroid - 58What is Hashimoto's disease?- Autoimmune disease
- Associated with thyroid peroxidase and thyroglobulin antibodies
- Low T3/T4 - 59Treatment for hypothyroidism- Levothyroxine
- 60Causes of hyperthyroidism- Graves - autoimmune
- Thyroid carcinoma
- Amiodarone deficiency - 61Treatment for Graves- Medical
- Surgical
- Radioactive iodine - 62Treatment for hyperthyroidism- Carbimazole - inhibits thyroid peroxidase so that iodine can't be oxidated
- Propylthiouracil - stops conversion of T4 to T3
- Beta blockers - activate sympathetic manifestations like fast heartbeat and sweating - 63What does parathyroid hormone do?Increases calcium concentration in the blood by increasing osteoclastic activity and increasing calcium resorption
- 64What is primary hyperarathyroidism?- When the parathyroid glands secrete too much PTH
- Leads to hypercalcaemia - dehydration, increased risk of fractures and GI infections
- Due to paraythyroid adenomas - 65What are the lateral hypothalamic centres for?Inducing hunger
- 66Where are the satiety centres in the hypothalamus?Ventromedial hyothalamus
- 67Name the main hormone released from hunger centresNeuropeptide Y neurons
- Increase food intake and reduce energy expenditure - 68What is the hormone released from satiety centres?Melanocortin
Decrease food intake and increase energy expenditure - 69What does Leptin do?Inhibits neuropeptide Y and activates melanocortin to reduce appetite
- 70What is Ghrelin?Increases appetite and is released into the stomach
- 71What other satiety hormones are released from the GI tract?Peptide YY and glucagon like peptide
- 72What is metabolic syndrome?3 or more of:
- Abdominal obesity
- Hpertriglyceridemia
- High BP
- Fasting hyperglycaemia - 73What are the long term problems associated with obesity?- Hypertension
- CHD
- Cancer - breast and colon
Type 2 diabetes
Arthritis - 74What are proximate factors of obesity?Causal factors/lifestyle
- 75What are evolutionary factors of obesity?Heritable traits/genetics
- 76Phases of sexual response cycle1. Desire
2. Arousal
3. Plateau
4. Orgasm
5. Relaxation - 77What is dyspareunia?Painful intercourse - can be superficial due to allergy or injury or can be deep due to infection
- 78What is the common precursor of steroids?Cholesterol from acetate
- 79What enzyme converts androgens into other oestrogens?Aromatase
- 80How do membrane receptor hormones act?Bind to membrane receptor and trigger a signal cascade that causes changes in the nucleus
- 81How do steroid hormones act?They can cross cell membranes and therefore elicit their responses directly on the nucleus. They bind to nuclear hormone receptors and induce a change which induces transcription factors to elicit a gene response.
- 82Where are female hormones located?Head and body
- 83What hormone is produced by the hypothalamus to produce FSH and LH?GnRH which acts on the anterior pituitary to express FSH and LH which elicit their changes on the ovaries
- 84When is the oocyte number fixed?3 months after conception
- 85At what stage of meiosis does the primary oocyte stop growing?Prophase - diplotenephase
- 86In what part of the gonad do primordial follicles reside in the female?Cortex
- 87What are the pulses of GnRH like in the preadolescent phase?Slow and irregular
- 88What is the follicular phase of the menstrual cycle defined as?The first day of menses and end of ovulation
- 89What happens in the early-mid follicular phase?Hypothalamus releases GnRH and this acts on the anterior pituitary to release FSH and LH.
- 90On what cells do FSH act?Granulosa cells
- Release androgen aromatase which converts androgens to oestrogen.
- Also produces inhibit B which negatively feedbacks FSH. - 91What hormones act on Theca cells?LH
- To make androgens - 92What hormone is essential for the regulation of follicular growth and where is it produced?- Granulosa cells
- Produce AMH - 93What change happens in granulosa cells mid-late follicular phase?- In response to high levels of oestrogen they start to display LH receptors
- Leads to plasma oestrogen surge - 94What happens at the oestrogen surge?Negative feedback of oestrogen is switched to a positive feedback. Anterior pituitary then starts to express oestrogen receptors so LH is increased leading to an LH surge
- 95What does a very high level of oestrogen do to thecal cells?Causes them to produce progesterone instead of oestrogen
- 96What occurs during ovulation?- 14 days
- Outer wall swells and stigma forms
- Stigma ruptures and ovum and mass of granulosa cells are carried
- LH acts on granulosa and theca cells to produce progesterone
- Ovulated egg is picked up by fallopian tubes - 97What happens in the luteal phase?- Ruptured follicle forms corpus luteum that secretes O and P.
- CL lasts for 14 days then undergoes luteolysis to form corpus albicans. - 98Describe the uterine cycle1. Menstrual phase - lining is shed
2. Proliferative phase - endometrium grows again and prepares for possible pregnancy
3. Secretory phase - blood supply to endometrium is remodelled and is supported by progesterone - 99Name some effects of oestrogen- Brain - helps to maintain body temp
- Breast - stimulates development
- Uterus - maturation
- Bones - preserve density - 100Name some of the menopausal symptoms- Hot flushes, menstrual irregularity, mood swings, depression and hirsuitism
- 101What gene is essential for male development?SRY gene
- 102Where the embryonic gonad arise from?Genital ridge primordia which forms from epiblast
- 103What areas do primordial germ cells colonise in a a) the female and b) the male?Female - cortex
Males - medulla - 104What happens to PGC's in males?- Become surrounded by coelimic epithelium to form tubules. These are precursors for seminiferous vesicles. These combine to form the rete testes.
- Also surrounded by pre-sertolli cells which produce androgens - 105What happens to PGC's in females?- Coelimic epithelium surrounds the PGC's to form follicles
- 106What do the mesopnephric cells form in the male and the female?Male - leydig cells, vascular tissue adn myoid cells
Female - theca cells and vascular tissue - 107When there is no SRY expressed what happens?FOXI2 is active and produces WNT4 which produces granulosa cells
- 108What two things are essential to male development?Androgens and AMH
- 109What forms the male reproductive system and female one?Male - wolffian duct
Female - mullerian duct - 110What do wolffian ducts develop into?Epididymis, vas deferens
- 111What do mullerian ducts develop into?Uterus and fallopian tubes
- 112What maintains the wolffian duct?Androgens produced by Leydig cells
- 113What causes regression of mullerian system in males?AMH
- 114What is gonadarche?The few years leading up to puberty
- 115What is turner syndrome?- Unpaired X chromosome
- Infertile - 116What is Klinefelters syndrome?- XXY
- Testes but not fertile
- Poor beard growth and breast development - 117What is androgen insensitivity syndrome?- Androgen is secreted by testes but target tissues fail to respond
- XY genotype but phenotypically female
- AMH acts on mullerian duct so have no internal genitalia - 118What is guevedoces?- Penis at 12
- Deficiency of 5a reductase enzyme which is necessary to make androgens
- Overcome at puberty - 119What is congenital adrenal hyperplasia?- XX
- Fetal adrenals are hyperactive to overcome low corticosteroid production of coritcosteroids
- Wolffian duct and mullerian duct retained
- Male external genitalia - 120Define adolescencePuberty and associated physiologcial development
- 121What is puberty?- State of becoming capable of reproduction
- 122What is adrenarche?- Adrenal development leading to puberty
- 123What is thelarche?Breast development towards puberty
- 124PubarcheDevelopment of pubic hair
- 125Menarche1st period
- 126ClimactericPeriod of life leading up last menstrual cycle
- 127MenopauseLast menstrual bleed (12 months)
- 128PerimenopausePeriod of life prior and 12 months after menopause
- 129Post menopauseLife after menopause
- 130What is the mechanism of action of oral contraception?- Contains oestrogens and progesterones
- Thickens cervical mucus
- Endometrial atrophy
- Inhibits ovulation - 131What does the IUD copper device do?Inhibits fertilisation as Cu is toxic to sperm and ovum
- 132Where does spermatogenesis occur?Sustencular cells
- 133What forms the blood testes barrier?Tightly bound sertolli cells that have gap junctions, tight junctions and connexins. Prevents autoimmune attack of spermatozoa.
- 134What do spermatic stem cells produce?Spermatogonium cells
- 135Process of sperm creation1. Spermatogonia
2. Spermatocytes
3. Spermatids
4. Spermatozoa - 136What is spermiogenesis?- Cytodifferentiation of round spermatods at the end of meiosis to functioning spermatozoa
- 137What is the spermatogenic wave?Spermatogenesis occurs in sequential waves along the length of the seminiferous tubules so that spermatozoa are produces in waves to ensure spermatozoa are produced continuously
- 138What does LH stimulate in males?Leydig cells to produce testosterone which is essential for spermatogenesis
- 139What is testosterone converted to?Dihydrotestosterone
- 140What does FSH do in the male?Binds to sertolli cells and stimulates production of androgen receptors
- 141What can high levels of prostate specific antigen be treated with?Gonadorelin antagonist - goserelin
Androgen receptor antagonists - bicalutamide
Reductase inhibitors - finasteride - 142OligozoospermiaLow sperm count
- 143AspermiaAbsence of semen
- 144AzoospermiaAbsence of sperm
- 145AsthenozoospermiaLow motility of sperm
- 146TeratospermiaAbnormal morphology of sperm
- 147Physiology of erection1. Sensory stimulation
2. Releases NO in corpus cavernosa
3. Causes expression of SGC which converts GTP to cGMP which is a vasodialator and causes erecetion - 148How to get back to detumescence?Decreased sensory stimulation, decreased NP, PPE5 is expressed which decreases formation of cyclic GMP and back to normal
- 149What does the cloaca seperate into?Rectum and urogenital sinus
- 150What ducts are obliterated in the male?Paramesopnephric ducts
- 151Epithelium in prostatic urethraTransitional epithelium
- 152Epithelium in membranous urethraPseudostratified columnar epithelium
- 153Epithelium in spongy/penile urethraStratified squamous
- 154What does the perineum contain?Anal canal, distal urethra, external genitalia
- 155Where does the urogenital triangle lie?Between the two ischial tuberosities and the pubic symphysis
- 156Where does the anal triangle lie?Lies betwene the two ischial tuberosities and the coccyx
- 157Muscles that make up the pelvic diaphragm- Coccygeus
- Levator ani - iliococcygeus, pubococcygeus and pubo rectalis - 158Clinical significance of the ischioanal fossaeInfections can spread through here
- 159Muscles important for maintaining continence in the superficial perineal pouchSuperficial transverse perineal muscles
- 160Innervation of the perineumPudendal nerve
- 161Innervation of the perineum (2)- Inferior hypogastric plexus
- Parasympathetic fibres - S2-S4 cause vasodialation, erection and bladder contraction
- Sympathetic fibres - T10-L2 cause smooth muscle contraction, internal urethral sphincter, reproductive tract and glands - 162Arteries of perineumInternal pudendal artery
- 163Veins of the pernieumInternal pudendal vein except deep dorsal veins of penis drain into prostate plexus
- 164What do the paramesopnephric ducts become?Oviducts and uterus
- 165What do the paramesonephric ducts attach to to form the vaginal canal?UROGENITAL SINUS
- 166Clinical significance of vesico and recto uterine pouchesInfections can collect here
- 167How is the uterus angled in comparison to the cervix?Anteflexed
- 168How is the vaginal canal angled to the cervix?Anterverted
- 1693 layers of the uterusEndometrium, myometrium and perimetrium
- 170What does the cervix have that causes cancers?Epithelial transition zone
- 171Epithelium of cervical canalSimple columnar
- 172Epithelium of ectocervix and vaginaStratified squamous
- 173Main blood supply of uterus- Comes from abdominal aorta and internal iliac arteries
- Seperates into vaginal, interior pudental and uterine arteries
Informações
- Descrição
- FlashCards sobre BLOCK 8 , criado por alishasruparelia em 28-05-2015.
- Criado por
- alishasruparelia
- Visualizações
- 1
- Avaliação