Tsarin jijiyoyi wani haɗaɗɗen tsari ne na matattarar jijiyoyi da ƙwayoyin halitta masu ɗaukar saƙo zuwa ƙwaƙwalwa da kuma ɗaukowa daga ƙwaƙwalwa da laka zuwa sassa daban-daban na jiki. Yin aiki mai kyau ga waɗannan jijiyoyi yana tabbatar da cewa kowane tsarin gaɓoɓin jiki, kamar tsarin zuciya da jijiyoyin jini da sashen gastrointestinal, da tsarin garkuwar jiki, suna iya ayyuka sosai da juna.
Tsarin jijiyoyi ya haɗa da rukunin jijiyoyi na tsakiya, wato central nervous system (CNS) da rukunin jijiyoyi da ake kira peripheral nervous system (PNS). Rukunin CNS ya ƙunshi ƙwaƙwalwa da laka (ƙashin baya), yayin da rukunin PNS ya ƙunshi tsarin somatic da tsarin jijiyoyi autonomic.
Ƙwaƙwalwa
A jikin matsakaitan mutane, ƙwaƙwalwa tana da nauyi tsakanin kilogram 1.3 zuwa 1.4, tare da kusan kashi 60% na ƙwaƙwalwar da ta kunshi kitse. Ragowar kashi 40% na ƙwaƙwalwar ya ƙunshi sinadaran furotin, ruwa, carbohydrates, da gishiri.
Ana iya raba ƙwaƙwalwa zuwa yankuna hudu daban-daban kamar haka: brainstem, cerebrum, cerebellum, da diencephalon. A haɗe, waɗannan bangarori daban-daban na ƙwaƙwalwa suna sarrafa tunani, ƙwaƙwalwar ajiya, motsin rai, taɓawa, ƙwarewar da dabara, gani, numfashi, jin yunwa, jin zafi ko sanyi, da sauran abubuwan da ke faruwa a cikin jiki.
Ƙwaƙwalwa ta ƙunshi launukan ƙasa-ƙasa da fari. Sashen da ke da launin ƙasa-ƙasa, wanda ya ɗan fi duhu ta fuskar launi, yana kewaye da fararen kwayoyin halitta, ya ƙunshi neuron somas, da kewayen jikin tantanin halitta. Yayin da farin sashen, wanda ya fi haske ta fuskar launi, ya ƙunshi ɓangaren ciki na ƙwaƙwalwa, kacokan an yi shi ne da ƙwayoyin halittar jijiya da ake kira axon, dogayen jijiyoyi masu haɗa ƙwayoyin halittar jijiya.
Brainstem
Wannan ɓangare na ƙwaƙwalwa, wanda ke tsakiyar ƙwaƙwalwa, shi ne ɓangaren ƙwaƙwalwa mai kama da tsintsiya wanda ke haɗa ƙwaƙwalwa da laka kuma yana da kusan tsayin inci ɗaya kawai. Wannan yanki yana daidaita ayyuka masu mahimmanci kamar hawan jini, numfashi, bugun zuciya, da haɗiya. Wannan ɓangare na ƙwaƙwalwa har ila yau an ƙara raba shi zuwa cikin midbrain da pons da medulla.
Midbrain
Wannan shi ne sashen wanda aka fi sani da mesencephalon, yana da mahimmanci wajen daidaita motsin ido, motsin rai, ji, da ƙwaƙwalwar ajiyar lokaci mai tsawo.
Pon
Shi ne wurin farawa na huɗu daga cikin 12 na jijiyoyin ƙoƙon kai. Wasu ayyuka daban-daban da pons yake tsarawa sun haɗa da motsin fuska, ji, numfashi, da ma’auni.
Medulla
Wannan sashe na nan a ƙasan ɓangarorin ƙwaƙwalwa inda ƙwaƙwalwa da laka ke haɗuwa. Wannan yanki na ƙwaƙwalwa yana daidaita numfashi, bugun zuciya, da hawan jini. Bugu da ƙari, medulla na kula da ayyuka kamar atishawa, amai, tari, da haɗiya.
Cerebrum
Ƙwaƙwalwar cerebrum ita ce mafi mahimmancin ɓangaren kwakwalwa kuma an lulluɓe ta da wani nau’in tantanin jijiyoyi mai zurfi wanda ake kira cerebral cortex. Wannan ɓangare yana a gaban ƙwaƙwalwa, an raba cerebram zuwa yankin dama da hagu na ƙwaƙwalwa, dukkansu sun haɗa da corpus callosum.
Yankin dama yana da alhakin samar da fahimta, motsin rai (farinciki da baƙinciki), yanayin fuska, da sauti, yayin da gefen hagu ya kasance mafi rinjaye a cikin harshe da kuma aiwatar da motsin zuciya. Yankin dama yana sarrafa ɓangaren hagu na jiki, yayin da yankin hagu ke sarrafa ɓangaren dama.
Cerebellum
Kwakwalwar cerebellum tana ƙarƙashin ɓangarorin wucin gadi da na occipital da kuma sama da gangaren ƙwaƙwalwa. Cerebellum tana da alhakin daidaita aikin dabarar sa-kai, (voluntary function). Binciken da aka yi kwanan nan ya nuna cewa cerebellum na iya ba da gudunmawa ga tunani, motsin rai, da halaye na zamantakewa.
Diencephalon
Diencephalon ya haɗa da thalamus da hypothalamus. thalamus shi ne cibiyar watsa bayanai don bayanan azanci, yayin da hypothalamus ke watsa ƙwayoyin sha’awa zuwa jiki ta hanyar glandar pituitary. Thalamus da hypothalamus, tare da amygdala da hippocampus, sun ƙunshi tsarin limbic. Amygdala tana sarrafa motsin rai, ƙwaƙwalwar ajiya, da damuwa, da sauran su.
Laka (spinal cord)
Laka jijiya ce mai tsayi mai kama da bututu wadda ta tashi daga ƙwaƙwalwa. Za a iya rarraba laka zuwa cikin cervical, thoracic, da yankunan lumbar da ke cikin wuya, kirji, da ƙasan baya.
Jimlar nau’i-nau’i 31 na jijiyoyi masu tsarin bibiyu da tushen jijiyoyin ne suka haifar da laka. Yankin laka wanda nau’in jijiyoyi na kashin baya ya samo asali shi ne ake kira da spinal segment. Kashin mahaifa (cervical) ya ƙunshi jijiyoyi takwas waɗanda suka samo asali daga wuya kuma suna gudana musamman zuwa fuska da kai.
Ana iya samun nau’i-nau’i na jijiyoyi goma sha biyu a cikin yankin thoracic na laka. Waɗannan jijiyoyi suna ba da izinin motsi a cikin jiki na sama, ciki har da tsawo na kirji, babba na baya, da ciki.
Akwai ƙarin jijiyoyi masu tsarin bibiyu guda goma da suka faro daga kasan baya, tare jijiyoyi masu tsarin bibiyu guda biyar a cikin lumbar da yankin sacral. Rukunin jijiyoyi na lumbar suna tafiya zuwa ƙafafu da ƙafafu, yayin da nau’i-nau’i na jijiyoyi na sacral sun shimfiɗu daga kasan baya zuwa cikin ƙashin ƙugu.
Meninges
Meninges wani nau’i ne na tantani guda uku waɗanda suke rufe da kuma kare duka ƙwaƙwalwa da laka. Tantanin meninges sun haɗa da dura mater, arachnoid, da pia mater.
Dura mater ita ce mafi ƙarancin tantanin meninges, kuma ta rabu zuwa kashi biyu, wato periosteal da meningeal. Layin meninges na tsakiya shi ne arachnoid, wani nau’i mai kama da yanar gizo na nama mai haɗi wanda bai ƙunshi kowace jijiyoyi ko jini ba. A ƙarshe, pia mater shi ne mafi ƙarancin tantanin mmeninges.
Neurons
Neuron, su ne ainihin tushen jijiyoyi, ƙwayoyin halittar jijiyoyi ne waɗanda ke karɓa da watsa saƙwannin jiki na jijiyoyi tsakanin ƙwaƙwalwa da sauran ɓangarorin jijiya. Neuron ya ƙunshi ƙwayar halittar jiki da dendrite da axon. Ƙwayar halittar jiki ta ƙunshi tsakiya, wanda ke sarrafa ayyukan ƙwayoyin halitta. Dendrites rassa ne waɗanda ke fitowa daga jikin tantanin halitta kuma suna karɓar saƙwanni daga sauran neurons.
Saƙwannin suna tafiya ta hanya mai tsawo kuma siririya, wannan hanya ita ake kira da axon, wanda ke fitowa daga jikin tantanin halitta. Waɗannan saƙwanni na sinadarai, waɗanda aka fi sani da neurotransmitters, suna tafiya tsakanin ƙwayoyin halittar jijiya ta hanyar wani sarari da ake kira da synapse.
Ƙwayoyin jijiyoyi suna ɗaukar saƙwanni daga jijiyoyi masu karɓar saƙo zuwa ƙwaƙwalwa, yayin da wasu jijiyoyin da ake kira motor neurons ke ɗaukar saƙwanni daga ƙwaƙwalwa zuwa wasu jijiyoyin da tsokoki.
Peripheral nervous system (PNS)
PNS ya ƙunshi dukkan bangarori biyu na tsarin jijiya wato somatic da autonomic. A haɗe, waɗannan ɓangarori suna aika bayanai daga sassa daban-daban na jiki zuwa ƙwaƙwalwa kuma suna tabbatar da cewa saƙwannin da aka aika daga ƙwaƙwalwa suna yaɗuwa zuwa wasu sassan jiki.
Somatic nervous system
Wannan tsari na somatic (SNS) ya ƙunshi zaruruwan jijiya waɗanda ke ɗaukar bayanan azanci ko ji daga gaɓoɓin zuwa sashen CNS. Wannan tsari na jijiya ya haɗa da zaruruwan jijiyoyi masu motsi waɗanda ke fita daga ƙwaƙwalwa don ɗaukar umarni da motsi zuwa tsokoki da ƙwarangwal.
Misali, idan aka taba abu mai zafi, jijiyoyi masu karɓar saƙwanni suna ɗaukar bayani game da zafin zuwa ƙwaƙwalwa. Daga baya, kwakwalwa, ta hanyar jijiyoyin motor neurons, ta umarci tsokoki na hannu su janye shi nan da nan. Wannan tsari yana ɗaukar ƙasa da daƙiƙa ɗaya don kammaluwa. Ƙwayar halittar jijiya ta jiki wadda ke ɗaukar wannan bayanin sau da yawa tana kwance a cikin ƙwaƙwalwa ko laka kuma tana aiki kai tsaye zuwa tsoka.
Autonomic nervous system
Wannan tsari da ake kira da autonomic nervous system (ANS), a Turance, yana sarrafa jijiyoyi na gaɓoɓin jiki waɗanda ba za a iya sarrafa su da niyya ba. Wannan ɓangare ya rarraba zuwa tsarin sympathetic, parasympathetic, da kuma enteric nervous systems. Wasu daga cikin ayyuka daban-daban da ANS ke aiwatarwa sun haɗa da bugun zuciya, narkewar abinci, numfashin, bugawar jini, da sha’awar jima’i.
Manazarta
Erulkar, D, S., Lentz, & L, T. (2025, May 14). Nervous system | Definition, Function, Structure, & Facts. Encyclopedia Britannica.
News-Medical. (2022, September 5). What is the Nervous System? Medical News.
Kenhub. (2023, November 3). Overview of the nervous system. Kenhub.
What are the parts of the nervous system? (2018, October 1). https://www.nichd.nih.gov/.
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