Apparato urinario

A. Apparato urinario umano: 1. Rene 2. Pelvi renale 3. Uretere 4. Vescica 5. Uretra
Altri organi: 6. Surrene 7. Fegato 8. Arteria e vena renale 9. Vena cava inferiore 10. Aorta addominale 11. Arteria e vena iliaca 12. Intestino crasso

L'apparato urinario è l'insieme di organi e di strutture finalizzati all'escrezione dell'urina o di altri prodotti del catabolismo in alcuni taxa animali, principalmente appartenenti ai cordati. Appartiene alla più vasta categoria degli apparati escretori animali, differenti per anatomia e fisiologia da gruppo a gruppo.

Funzione

La funzione principale dell'apparato urinario è l'eliminazione dei rifiuti metabolici, principalmente dei composti azotati; i gruppi amminici non riutilizzati dall'organismo per sintetizzare nuovi composti azotati vengono escreti sotto diverse forme chimiche:

  • gli animali che producono come composto terminale urea vengono detti ureotelici
  • le specie animali che producono ammoniaca sono detti ammoniotelici
  • gli animali che producono acido urico sono chiamati uricotelici.

Fonte principale dell'azoto catabolico sono gli amminoacidi che, nei mitocondri, vanno incontro alla deaminazione ossidativa via glutammato deidrogenasi.

Lo ione ammonio risultante reagisce col glutammato, via glutammina sintetasi, formando glutammina, che trasporta i gruppi amminici al fegato. Dal metabolismo muscolare l'alanina è invece il principale vettore, sempre verso il fegato; origina dal trasferimento glutammato-piruvato dell'aminogruppo. Nello stesso fegato tramite il ciclo dell'urea nei mammiferi, ed altri cicli in differenti taxa animali, l'azoto viene convertito in ammoniaca, acido urico od urea, per essere infine eliminato.

Apparato urinario umano

Sistema urinario

Come in tutti i mammiferi l'ammoniaca, presente in forma protonata come ione ammonio, viene convertita in urea tramite il già citato ciclo dell'urea o dell'ornitina citrullina, che permette, a fronte d'una spesa energetica di due molecole di ATP per ogni molecola di urea prodotta, di disporre di un composto meno tossico rispetto a quello di partenza. L'escrezione di questa e altre molecole viene attuata dai nefroni, principali attuatori dell'apparato urinario.

Nell'essere umano, l'apparato è rappresentato da:

L'organo principale dell'apparato escretore, il rene, è costituito da una zona midollare, costituita dalle piramidi renali, ed una corticale. L'unità funzionale del rene è il nefrone, costituito dal corpuscolo di Malpighi a sua volta composto dal glomerulo, dalla capsula di Bowman e dal tubulo renale. Il sangue, tramite l'arteriola afferente, arriva nel glomerulo dove, a causa della pressione determinata dalla presenza di un'arteriola efferente di diametro molto minore e dalla presenza di fenestrature di questo vaso che contribuiscono alla variazione della pressione, attraversa un filtro formato dai podociti. Al termine di questo processo si ottiene l'ultrafiltrato glomerulare (1.60-1.80 litri/die), che deve però essere ulteriormente filtrato prima di diventare urina (1.5 litri/die). Passa così nel tubulo renale, formato da un tubulo contorto prossimale, dall'ansa di Henle, da un tubulo contorto distale e dal dotto collettore. In questo percorso, dall'ultrafiltrato vengono riassorbiti acqua e ioni sodio, fino ad ottenere l'urina.

Voci correlate

Altri progetti

Collegamenti esterni

Controllo di autoritàThesaurus BNCF 23465 · LCCN (ENsh85141406 · GND (DE4023494-0 · BNE (ESXX532100 (data) · BNF (FRcb11976904m (data) · J9U (ENHE987007529764705171 · NDL (ENJA00563231

Read other articles:

PT Bank Pembangunan Daerah Maluku dan Maluku UtaraBank Maluku MalutIndustriPerbankanDidirikan25 Oktober 1961KantorpusatJalan Raya Pattimura No. 09, Ambon, Maluku, IndonesiaTokohkunciArief Burhanudin Waliulu (CEO), Nadjib Bachmid (Komisaris Utama)PendapatanRp 735.663 miliar (2016)Laba operasiRp 218.013 miliar (2016)Laba bersihRp 140.674 miliar (2016)Total asetRp 5.644 triliun (2016)Total ekuitasRp 731.163 miliar (2016)Situs webSitus Resmi Bank Maluku PT Bank Pembangunan Daerah Maluku dan Maluk...

 

 

Artikel ini bukan mengenai Dewan Uni Eropa atau Majelis Eropa. Dewan EropaLambangTanggal pendirian1961 (informal)2009 (formal)TipeKepresidenan kolektif UELokasiGedung Europa, BrusselsPresidenCharles MichelSitus webEuropean Council Uni Eropa Artikel ini adalah bagian dari seri: Politik dan pemerintahanUni Eropa Parlemen Presiden Jerzy Buzek Kelompok terbesar; Joseph Daul: EPP Martin Schulz: S&D Sesi ke-7 AP (736) Periode 2009-14 Biro Wakil Presiden Quaestor Konferensi Prosedur legislatif D...

 

 

Model ruang terisi ferosena, tipikal senyawa sandwich Dalam kimia organologam, sebuah senyawa apit adalah senyawa kimia yang menampilkan logam yang diikat oleh ikatan kovalen haptik pada dua ligan arena. Arena memiliki rumus kimia CnHn, dan turunan tersubstitusinya (misalnya Cn(CH3)n) dan turunan heterosiklik (misalnya BCnHn+1). Oleh karena logam biasanya berada di antara dua cincin, maka logamnya disebut ter-apit. Kelompok khusus kompleks apit adalah metalosena. Istilah senyawa apit diperken...

For the Navy officer, see Jean-Jacques Magendie. François MagendieFrançois Magendie in 1822Born6 October 1783Bordeaux, FranceDied7 October 1855 (aged 72)Sannois, FranceNationalityFrenchKnown forForamen of Magendie Bell-Magendie lawScientific careerFieldsPhysiology François Magendie (6 October 1783 – 7 October 1855) was a French physiologist, considered a pioneer of experimental physiology. He is known for describing the foramen of Magendie. There is also a Magendie sign, a downw...

 

 

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Heterocyclic amine formation in meat – news · newspapers · books · scholar · JSTOR (September 2015) (Learn how and when to remove this template message) A well-done steak, with accompaniments. The black lines where it has rested on the grill will contain heter...

 

 

مسجد الملكة صفية إحداثيات 30°02′26″N 31°15′15″E / 30.04051°N 31.25428°E / 30.04051; 31.25428  معلومات عامة القرية أو المدينة القاهرة الدولة مصر سنة التأسيس 1610  تاريخ بدء البناء 1610م التصميم والإنشاء النمط المعماري الدولة العثمانية معلومات أخرى ويكيميديا كومنز مسجد الملكة صفية...

Former association football club in Scotland Not to be confused with Renfrew F.C.. Renfrew Football Club was a Scottish football team located in the town of Renfrew. Football clubRenfrewFull nameRenfrew F.C.Founded1875Dissolved1890GroundGlebe ParkSecretaryJames Syme[1] Home colours History 1877–78 Scottish Cup 1st Round, Pollokshaws 0–2 Renfrew, Paisley Daily Express, 8 October 1877 The club was founded in 1875, with 30 members in its first season.[2] The club's first reco...

 

 

SEMARANG SELATANKecamatanPeta lokasi Kecamatan SEMARANG SELATANNegara IndonesiaProvinsiJawa TengahKotaSemarangPemerintahan • Camat-Populasi • Total- jiwaKode Kemendagri33.74.07 Kode BPS3374050 Luas5,93 km²Desa/kelurahan- Semarang Selatan (bahasa Jawa: ꦱꦼꦩꦫꦁ​​ꦏꦶꦢꦸꦭ꧀, translit. Semarang Kidul) adalah sebuah kecamatan di Kota Semarang, Provinsi Jawa Tengah, Indonesia. Kelurahan-kelurahan yang terletak di kawasan Semarang Selatan ya...

 

 

British neurobiologist (1944–2022) SirColin BlakemoreFRS FMedSci HonFRCP HonFRSM FRSB FBPhSBlakemore in 2012BornColin Brian Blakemore(1944-06-01)1 June 1944Stratford-upon-Avon, EnglandDied27 June 2022(2022-06-27) (aged 78)Oxford, EnglandAlma mater University of Cambridge (MA) University of California, Berkeley (PhD) Spouse Andrée Elizabeth Washbourne ​ ​(m. 1965; died 2022)​[2]Children3, including Sarah-Jayne...

19th-century U.S. Army officer For the English rugby union player, see George Crook (rugby union). General Crook redirects here. For the musician, see General Crook (musician). George CrookPortrait of George CrookNickname(s)Nantan Lupan, which means Grey Wolf; “Three Stars” to the LakotaBorn(1828-09-08)September 8, 1828Taylorsville, Ohio, USDiedMarch 21, 1890(1890-03-21) (aged 61)Chicago, Illinois, USPlace of burialArlington National CemeteryAllegianceUnited States of AmericaUnionSer...

 

 

Protestant Christian denomination dating back to the 15th century Unitas Fratrum redirects here. For other uses, see Unity of the Brethren.This article may contain unverified or indiscriminate information in embedded lists. Please help clean up the lists by removing items or incorporating them into the text of the article. (June 2024)Unity of the BrethrenLatin: Unitas FratrumA stained glass emblem of Agnus Dei at Trinity Moravian Church in Winston-Salem, North CarolinaClassificationProto-Prot...

 

 

Artikel ini sebatang kara, artinya tidak ada artikel lain yang memiliki pranala balik ke halaman ini.Bantulah menambah pranala ke artikel ini dari artikel yang berhubungan atau coba peralatan pencari pranala.Tag ini diberikan pada September 2016. Akhmad AmetLahirAkhmad Amet29 April 1987 (umur 37)Bandung, Jawa Barat, IndonesiaKebangsaanIndonesiaNama lainAmet, Akhmad IcipPendidikanPoliteknik LP3I BandungPekerjaanPresenter, Penyiar RadioTahun aktif2006–sekarang Akhmad Amet atau ...

American singer (1936–2013) Bobby SmithSmith in 1977Background informationBirth nameRobert Steel SmithAlso known asBobbie SmithBorn(1936-04-10)April 10, 1936Detroit, Michigan, U.S.DiedMarch 16, 2013(2013-03-16) (aged 76)Orlando, Florida, U.S.GenresPop, R&B, soulOccupation(s)SingerYears active1954–2013Musical artist Robert Steel Smith (April 10, 1936 – March 16, 2013),[1] professionally known as Bobby Smith, also spelled Bobbie, was an American R&B singer notable...

 

 

Artikel ini sebatang kara, artinya tidak ada artikel lain yang memiliki pranala balik ke halaman ini.Bantulah menambah pranala ke artikel ini dari artikel yang berhubungan atau coba peralatan pencari pranala.Tag ini diberikan pada Februari 2023. CZ adalah singkatan dari Česká zbrojovka yang berarti Gudang Senjata Ceko dan tanda ini digunakan pada produk senjata api buatan Ceko. Sebagian besar senjata api bertanda CZ dihubungkan dengan Česká zbrojovka Uherský Brod (ČZUB)-produsen senjata...

 

 

Pour le traité de 1416, voir Traité de Canterbury (1416). Traité de CantorbéryTitre original (en-GB) Treaty concerning the construction and operation by private concessionaires of a channel fixed linkNom officiel Traité concernant la construction et l'exploitation par des sociétés privées concessionnaires d'une liaison fixe transmancheFormat TraitéLangues Français, anglaisDate 29 juillet 1987Pays France, Royaume-Unimodifier - modifier le code - modifier Wikidata Le traité de ...

Cet article est une ébauche concernant un acteur et un chanteur japonais. Vous pouvez partager vos connaissances en l’améliorant (comment ?) selon les conventions filmographiques. Pour les articles homonymes, voir Hoshino  et Hoshino  (homonymie). Gen Hoshino Gen Hoshino en 2017.BiographieNaissance 28 janvier 1981 (43 ans)Warabi (Japon)Nom dans la langue maternelle 星野 源Nationalité  JaponaisFormation Freedom Forest Gakuen Junior et Lycée (d)Écol...

 

 

2007 Parti Québécois leadership election ← 2005 26 June 2007 2015 →   Candidate Pauline Marois Party Parti Québécois Popular Vote Acclaimed Leader before election André Boisclair Elected Leader Pauline Marois The Parti Québécois leadership election of 2007 elected the seventh leader of the Parti Québécois, the main political party to promote Quebec independence in Quebec, Canada, and was won by Pauline Marois. Former PQ Minister Pauline Marois was the firs...

 

 

皮埃尔·路易吉·贝尔萨尼Pier Luigi Bersani意大利民主党总书记任期2009年10月25日—2013年4月20日前任达里奥·弗朗西经济发展部部长任期2006年5月17日—2008年5月8日前任Claudio Scajola继任Claudio Scajola 个人资料出生 (1951-09-29) 1951年9月29日(72歲) 義大利贝托拉政党 民主黨配偶Daniela Ferrari专业政治家宗教信仰羅馬天主教 学历 博洛尼亚大学 皮埃尔·路易吉·贝尔萨尼(意大利语:Pier ...

Polish footballer and manager You can help expand this article with text translated from the corresponding article in Polish. (October 2021) Click [show] for important translation instructions. View a machine-translated version of the Polish article. Machine translation, like DeepL or Google Translate, is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-translate...

 

 

le Crésançon Caractéristiques Longueur 11,7 km Bassin collecteur Loire Régime pluvial Cours Source près du hameau des Bruyères · Localisation Le Donjon · Altitude 383 m · Coordonnées 46° 19′ 02″ N, 3° 46′ 04″ E Confluence la Vouzance · Localisation Neuilly-en-Donjon · Altitude 271 m · Coordonnées 46° 20′ 24″ N, 3° 53′ 16″ E Géographie Pays traversés France Département Allier Régio...