Laka: tsarin fasali, iri da kuma ayyuka

The laka ne wani ɓangare na tsakiya m tsarin. A jikin mutum shi ne ke da alhakin motor reflexes da kuma watsa jijiyar tsakanin gabobin da kuma kwakwalwa. laka rufe shi, samar da kariya. Mene ne siffofin da kuma bambance-bambance ba su da?

tsarin

vertebral arches samar da wata rami, da ake kira vertebral canal, kuma a cikinta ne wani laka tare da tasoshin da kuma jijiya asalinsu. Its babba part an haɗa zuwa medulla (shugaban sashen), da kuma kasa - tare da periosteum biyu coccygeal vertebra.

Laka kama wani bakin ciki da farin line, da tsawon wadda a mutumin ya kai 40-45 santimita, da kuma kauri ƙaruwa daga kasa zuwa sama. Its surface ne dan kadan concave. Ya kunshi talatin da daya segments na wanda aka located a biyu daga jijiya asalinsu.

The laka an rufe tare da bawo a waje. Ciki shi ya ƙunshi wani m da fari al'amari, su rabo dabam a sassa daban-daban. The m al'amarin yana cikin siffar wani malam, akwai jijiya cell jikin da su tafiyar matakai qunshi wani farin m, wanda aka shirya a gefuna.

A cibiyar tashar aka located m al'amarin. Yana cika da cerebrospinal ruwa (CSF), wanda aka ci gaba da kẽwayãwa a cikin kwakwalwa da kuma laka. A manya, shi ne har zuwa girma na 270 milliliters. CSF samar a cikin ventricles na kwakwalwa da kuma aka wallafa 4 sau a rana.

laka

Uku harsashi: wuya, arachnoid da kuma taushi - rufe duka biyu, kai kuma da laka. Sun yi biyu main ayyuka. M hana mummunan tasiri na inji mataki a kan kwakwalwa. Trophic aiki ne alaka da tsari na cerebral jini ya kwarara, godiya ga wanda yana da za'ayi metabolism a kyallen takarda.

laka an hada da connective nama Kwayoyin. Waje akwai mai wuya harsashi, ƙarƙashin arachnoid da kuma taushi. Su ba dab da juna tam. Yana yana subdural da kuma tsakanin da subarachnoid sarari. Don kashin baya da suka haɗa da faranti da jijiyoyin, wanda hana elongation daga cikin kwakwalwa.

Shell suna kafa a farkon watan biyu na fetal ci gaba. A connective nama yana kafa a na tsarin jijiya tube da kuma rarraba tare da shi. Daga baya nama Kwayoyin rabu ta samar da m da ciki harsashi. Bayan wani lokaci na ciki harsashi ne zuwa kashi taushi da kuma arachnoid.

tukuru harsashi

A matsanancin harsashi kunshi wani m saman da kasa yadudduka. Yana yana da wani m surface a kan wanda aka zubar a jam'i na receptacles. Ba kamar mai kama da harsashi a cikin kwakwalwa, shi ya aikata ba kafa uku tam da ganuwar da vertebral canal kuma rabu da su da venous plexus, m nama.

The wuya harsashi na laka ne m fibrous nama m. Da ya ƙunsa kwakwalwa a cikin nau'i na wani elongated cylindrical siffar da jakar. Rufe sel (endothelium) sun dauki wani m cladding Layer.

Yana encapsulates nodes da jijiyoyi, kafa wani kogo wanda fadada, gabatowa da intervertebral foramen. Kusa da shugaban harsashi da aka haɗa ta occipital kashi. Yana Narrows saukar da wani bakin ciki kirtani, wanda aka haɗe da coccyx.

Jini ya wuce ta jijiyoyi da harsashi da alaka da thoracic da kuma na ciki lakã. Venous jini shiga venous plexus. A harsashi da ake gyarawa a cikin kashin baya canal ta wajen tafiyar matakai a intervertebral foramen kuma fibrous tufts.

arachnoid

Ramin-dimbin yawa sarari tare da manyan yawan ha bim mai ɗamfarar raba da arachnoid membrane na laka. A karshen yana da wani nau'i na bakin ciki takardar, shi ne m, kuma ya ƙunshi fibroblasts (connective nama zaruruwa cewa haduwa da extracellular matrix).

Arachnoid membrane na laka nade glia - Kwayoyin cewa samar da watsa daga jijiyar. Ya ƙunshi wani jini. Daga arachnoid tafi matakai, filamentous trabeculae, saƙa a cikin wadannan m harsashi.

Karkashin cover located subarachnoid sarari. Ciki da shi yana dauke da cerebrospinal ruwa. Yana fadada a cikin ƙananan ɓangare na laka, a cikin sacrum da coccyx. A wani wuyansa yankin dake tsakanin gagara kuma taushi arachnoid membranes. Septum da kaya mahada tsakanin kwakwalwa jijiya tushen tsayayyen a wuri guda, ba kyale shi ya motsa.

m harsashi

Inner harsashi ne taushi. Da ya ƙunsa da laka. Idan aka kwatanta da irin wannan tsarin a cikin kwakwalwa, an dauke mafi m da kuma lokacin farin ciki. Soft harsashi na laka kunshi sako-sako da nama, wanda aka rufe da endothelial Kwayoyin.

Yana yana da biyu na bakin ciki yadudduka tsakanin wanda akwai da yawa jini. A saman Layer, da zane na bakin ciki farantin ko takardar ne dentate jijiyoyin cewa kafa harsashi. Don na ciki na da m membrane na glial Kwayoyin an haɗa kai tsaye zuwa cikin laka. A harsashi Forms daina kai hare hare ga jijiya da kuma tare da shi da ke shiga cikin kwakwalwa da kuma m al'amarin.

Soft harsashi ne ba kawai a cikin dabbobi masu shayarwa. Sauran terrestrial vertabrate (tetrapods) da kawai biyu - m da ciki. A cikin shakka daga juyin ci gaba da ciki da harsashi a cikin dabbobi masu shayarwa da aka raba a kan yanar gizo da kuma taushi.

ƙarshe

The laka aka alaka da tsakiya m tsarin na vertabrate, ciki har da mutane. Shi aikin da aiki na reflex da introducer. A farko reshe reflexes alhakin - .. Daga lankwashewa da tsawo, jijjiga gefen, da dai sauransu The biyu aiki ne a aiwatar da jijiyar tsakanin gabobin da kuma kwakwalwa.

M, arachnoid da kuma taushi harsashi ƙunsa da laka daga waje. Sun yi m da trophic (sinadirai) aiki. Bawo kafa connective nama Kwayoyin. Sun rabu da sarari tsakanin su wadda aka cika da sayar da giya - ruwa circulating a cikin laka da kuma kwakwalwa. A casing alaka tsakanin lafiya zaruruwa da kuma matakai.