Powerpoint excretion and the kidneys
- 1. EXCRETION AND THE KIDNEYS
- 2. EXCRETIONTheremovalfromorganisms of: - toxicmaterials, - thewasteproducts of metabolism (chemicalreactions in cellsincludingrespiration) and - substancesin excess of requirements.
- 3. ExcretionEgestionEGESTION: Isthepassing out of food that has not been digested, as faeces, through the anus.
- 5. LUNGS: carbondioxideand watervapour (incidental)
- 6. KIDNEYS: urea, water, salts, toxins, hormones, drugs.
- 8. SKIN: water, salts, urea (incidental losses)
- 9. EXCRETORY PRODUCTS AND INCIDENTAL LOSSES
- 10. LIVERFunctionsRegulation of bloodsugars.Production of bile.DeaminationStorage of iron.Manufacture of plasma proteins.Detoxication: breakingdown of alcohol, drugsBreakingdown of hormones.Storage of vitamins
- 11. Alcohol and theliverTheliverreceivesalltheuseful and harmfulmoleculesthatthegutabsorbsfromfood. Drugsorpoison are harmfulmolecules.Alcoholis a drug. Itaffectsthe normal working of thebody.Itis absorbed fromthestomach and liver.Thecell of theliverconvert alcohol in anothersubstancewhichdoesnotpassthroughtherest of thebody´scirculation.
- 12. AlcoholIn workingtoprotectothertissuestheliverislikelytoharmitself.Thesubstanceproducedfrom alcohol can bedangeroustothelivercells in highconcentration.It can cause a seriousdiseasecalledcirrhosis.Iftheliverisdamagedbyexcessive alcohol consumption, thentheholebodyisaffected.E.g: Bloodglucoseconcentrationcannotbecontrolledefficiently.
- 13. KIDNEYS:Structure: Fairlysolid,oval, red-brown and attachedtothe abdominal cavity.
- 14. Renal artery: ?
- 15. Renal veins: ?
- 16. Longitudinal section: 3 mainparts: - cortex, medullaand pelvis.- Leadingfromthe pelvis is a tube, calledureter, whichcarriesurinethatthekidney has madetothebladder.
- 19. NEPHRONIs a single glomerulus(tangle of bloodcapillaries), withitsrenal capsule, renal tubeand bloodcapillaries.Kidneys are made of thousands of nephrons.Eachnephronbegins in thecortex, loopsdown in themedulla, back intothecortex, and thengoesdownagainthroughthemedullatothe pelvis.In the pelvis thenephronsjoin up withtheureter.
- 21. KIDNEY: FUNCTION1) FILTRATION: - Bloodisbroughttothe renal capsule in a branch of the renal artery. - Onlysmallmolecules can gothrough. They are squeezedout of thebloodintothe renal capsule. - Water, salt, glucose and urea. - Mostproteins are toobig, so theystay in thebloodalongwithbloodcells.
- 22. KIDNEY:FUNCTION2) REABSORPTION:- Some of thesubstances in the fluid in the renal capsule are neededbythebody. - All of theglucose, some of thewater and some of thesaltsneedtobekept in theblood. - Usefulesubstances in thekidneytubuleare reabsorbed and pass back intotheblood in thebloodcapillarieswrappedaroundeachkidneytubule. - Theremaining fluid continuesonitswayalongthetubule - In thecollectingductitismostlywater, with urea and saltsdissolved in it. ItiscalledURINE.
- 24. THE BLADDER STORES URINETheurinefromallthenephronsflowsintotheureterswhichtakeittothebladder.Thebladderstoresurine.Whenitisfulled, thesphinctermuscle opens and theurineflowsalongtheurethra and out of thebody.
- 26. DIALYSISMaintenance of glucose and protein concentration in blood and diffusion of urea from blood to dialysis fluid, which has water, glucose, salts that should be present in the blood. Inside the machine the blood is separated from the dialysis fluid by a partially permeable membrane. Dialysisdoesthework of damagedkidneys.Patientsneedtobetreatedtwoorthree times a week and thetreatmentlastsforseveralhours (disadvantageApplication of dialysis in kidneymachines:
- 29. Thebesttreatmentis a KIDNEYTRANSPLANTbut: THE IMMUNE SYSTEM CAN REJECT TRANSPLANTS:Thepersonreceivingthetransplantistherecipient.Thepersonfromwhoseorganthebodywastakenisthedonor.Therecipient´simmunesystemrecognisesthedonororgan as being “foreign”, and attaksit. ThisiscalledREJECTION.Therecipientisgivendrugscalledimmunosuppresants. Thetroubleisthatthey stop theimmunesystemfromdoingits normal job, so thepersonis more likelytosufferfromallsorts of infectiousdiseases.The chances of rejection are reducedifthedonoris a closerelative of therecipient, becausethey are more likelytohaveantigensontheircellswhich are simmilartoeachother, so therecipient´simmunesystemislesslikelytoreacttothedonatedorgan as itwere ¨foreign¨.
- 30. SuccessfulkidneytransplantshaveadvantagesoverdyalisistreatmentIn thelongterm, a transplantismuchcheaper.Thepatient´slifeislessdisrupted once theyhaverecoveredfromtheoperation.