Biology

**Biology** shine binciken kimiyya na tsirrai. Kimiyyar ɗabi'a ce mai fa'ida amma yana da jigogi masu haɗa kai da yawa waɗanda suka haɗa shi a matsayin fage guda ɗaya, daidaitacce.    Misali, dukkan ƙwayoyin halitta sun ƙunshi sel (cell) waɗanda ke sarrafa bayanan gada da aka sanya a cikin ƙwayoyin halitta, waɗanda za'a iya yaɗa su zuwa ga tsararraki masu zuwa. Wani babban jigo shine juyin halitta, wanda ke bayyana haɗin kai da bambancin rayuwa.    Har ila yau sarrafa makamashi yana da mahimmanci ga rayuwa yayin da yake ba da damar kwayoyin halitta su motsa, girma, da kuma haifuwa.    A ƙarshe, duk kwayoyin halitta suna iya daidaita mahallin nasu na ciki.     

Masanan halittu suna iya yin nazarin rayuwa a matakai daban-daban na tsari,  daga ilimin kwayoyin halitta na tantanin halitta zuwa yanayin jiki da ilimin halittar tsirrai da dabbobi, da kuma juyin halittar al'umma.   Don haka, akwai ƙasƙanci da yawa a cikin ilimin halitta, kowanne an bayyana shi ta yanayin tambayoyin binciken su da kayan aikin da suke amfani da su.    Kamar sauran masana kimiyya, masu ilimin halitta suna amfani da hanyar kimiyya don yin abubuwan lura, gabatar da tambayoyi, samar da hasashe, yin gwaje-gwaje, da kuma samar da karshe game da duniya da ke kewaye da su. 

Rayuwa a Duniya, wacce ta bayyana fiye da shekaru biliyan uku  da dugo bakwai 3.7 da suka wuce,  tana da banbanci sosai. Masanan halittu sun nemi yin nazari da rarraba nau'o'in rayuwa daban-daban, daga kwayoyin prokaryotic kamar su archaea da kwayoyin cuta zuwa kwayoyin eukaryotic kamar su protists, fungi, shuke-shuke, da dabbobi. Wadannan kwayoyin halitta daban-daban suna ba da gudummawa ga nau'in halittun halittu, inda suke taka rawa na musamman a cikin hawan keke na gina jiki da makamashi ta hanyar yanayin halittarsu.

Ilimin halitta ya kunsa nazari akan sassa guda biyu wanda ya hada da:

# Nazari akan dabbobi (zoology).
# Nazari akan shukoki (botany).
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## Tarihi.

Farkon tushen kimiyya, wanda ya hada da magani, ana iya samo shi daga tsohuwar Masar da Mesopotamiya a kusan dubu uku 3000, zuwa 
dubu daya da dari biyu  1200 KZ.   Gudunmawarsu ta haifar da tsohuwar falsafar halitta ta Girka.     Masana falsafa na Girka na da irin su Aristotle (384-322 KZ), sun ba da gudummawa sosai ga hadaka ilimin halittu. Ya bincika abubuwan da ke haifar da ilimin halitta da bambancin rayuwa. Magajinsa, Theophrastus, ya fara nazarin kimiyyar shuke-shuke.  Malaman duniyar Islama ta tsakiya wadanda suka yi rubuce-rubuce kan ilmin halitta sun hada da al-Jahiz (781-869), Al-Dīnawarī (828-896), wanda ya yi rubuce-rubuce a kan ilmin ilmin halitta,  da Rhazes (865-925), wanda ya yi rubuce-rubuce a kan ilmin jikin mutum da physiology. Masana ilimin addinin Musulunci da ke aiki a al'adun falsafar Girka sun yi karatun likitanci sosai, yayin da tarihin dabi'a ya jawo hankalin Aristotelian sosai.

Ilimin halitta ya fara hadaka da sauri tare da ingantaccen na'ura na Anton van Leeuwenhoek. A lokacin ne masana suka gano spermatozoa, kwayoyin cuta, infusoria da kuma bambancin rayuwa na microscopic. Binciken da Jan Swammerdam ya yi ya haifar da sabon sha'awar ilimin halitta kuma ya taimaka wajen hadaka dabarun barna da tabo.  Ci gaban da aka samu a microscopy ya yi tasiri sosai kan tunanin halittu. A farkon karni na  sha tara 19, masana ilmin halitta sun nuna mahimmancin tantanin halitta . A cikin 1838, Schleiden da Schwann sun fara hadaka ra'ayoyin duniya na yanzu cewa (1) ainihin rukunin kwayoyin halitta shine tantanin halitta da (2) cewa sel guda daya suna da duk halayen rayuwa, kodayake sun yi adawa da ra'ayin cewa (3) duk sel sun zo. daga rarrabuwar wasu sel, ci gaba da tallafawa tsarar da ba ta dace ba . Duk da haka, Robert Remak da Rudolf Virchow sun sami damar sake inganta ka'idar ta uku, kuma a cikin 1860s yawancin masanan halittu sun yarda da dukkanin rukunan guda uku wadanda suka hada cikin ka'idar tantanin halitta .  

A halin yanzu, taxonomy da rarrabuwa sun zama abin da masana tarihi suka fi mayar da hankali kan abubuwan tarihi. Carl Linnaeus ya wallafa wani ka'idar taxonomy na duniya a cikin 1735, kuma a cikin 1750s ya gabatar da sunayen kimiyya ga dukan nau'insa.  Georges-Louis Leclerc, Comte de Buffon, sun bi da nau'in nau'in nau'i na wucin gadi da nau'i na rayuwa kamar yadda ba za a iya yin su ba - har ma yana nuna yiwuwar zuriya na kowa. 

Tunanin juyin halitta mai tsanani ya samo asali ne daga ayyukan Jean-Baptiste Lamarck, wanda ya gabatar da ka'idar juyin halitta.  Masanin ilimin halitta na Biritaniya Charles Darwin, ya haɗu da tsarin biogeographical na Humboldt, ilimin yanayin kasa na Lyell, rubuce-rubucen Malthus game da hadakar yawan jama'a, da kwarewar ilimin halittarsa da kuma manyan abubuwan lura na halitta, sun kirkira ingantaccen ka'idar juyin halitta bisa zabin yanayi; irin wannan dalili da shaida ya jagoranci Alfred Russel Wallace don cimma matsaya iri daya. 

Tushen tushen kwayoyin halitta na zamani ya fara ne da aikin Gregor Mendel a 1865.  Wannan ya zayyana ka'idodin gadon halittu.  Duk da haka, ba a fahimci mahimmancin aikinsa ba har zuwa farkon karni na ashirin 20 lokacin da juyin halitta ya zama ka'idar hadin kai yayin da tsarin zamani ya daidaita juyin halittar Darwiniyanci da kwayoyin halitta na gargajiya.  A cikin 1940s da farkon 1950s, jerin gwaje-gwajen da Alfred Hershey da Martha Chase suka yi sun nuna DNA a matsayin bangaren kwayoyin chromosomes wadanda ke dauke da nau'o'in halayen da aka sani da kwayoyin halitta . Mai da hankali kan sabbin nau'ikan kwayoyin halitta irin su kwayoyin cuta da kwayoyin cuta, tare da gano tsarin DNA mai karfi biyu na James Watson da Francis Crick a cikin shekarar dubu daya da dari tara da hamsin da uku 1953, ya nuna sauyi zuwa zamanin kwayoyin kwayoyin cuta. Daga shekarar dubu daya da dari tara da hamsin 1950 zuwa gaba, ilmin halitta ya kara fadada sosai a fannin kwayoyin halitta . Har Gobind Khorana, Robert W. Holley da Marshall Warren Nirenberg ne suka fashe lambar halittar bayan da aka fahimci DNA na dauke da codons . An kaddamar da aikin Human Genomy a cikin karni na dubu daya da dari tara da cassa'in 1990 don taswirar halittar dan adam . 

## Manazarta.