Министерство высшего и среднего специального образования Республики Узбекистан

Neyron-asab tizimining asosiy birligi

Ma’ruza mashg’ulotlari

Inson tanasi va hokazo suyak hujayralari, mushak hujayralari, tana hujayralari, deb hujayralari turli turdagi iborat Har bir turi alohida vazifasi bor bir birlik shakllantirish, kichik hujayralari millionlab topgan. bir tana qismi elektr xabarlar burchi nerv hujayralari uchun tayinlandi. Bizning asab tizimi nerv hujayralari iborat. uning barcha filiallari bilan bir asab hujayrasi neyronlarning deyiladi. Bu neyronlarning asab tizimining yakuniy tuzilishi va funktsional birligi hisoblanadi. bir shaxsning asab tizimida neyronlar soni 200 milliard 100 baholanmoqda. Ular, asosan, tarkibida bir xil bo'ladi, lekin maxsus vazifalar uchun mo'ljallangan turli uzunliklar, shakl va darajada ko'rinadi. Har bir neyrondagi ichida DNK dan genetik ko'rsatmalar oshiruvchi har biri RNK molekulalari, millionlab bor.¹[4]

The human body is composed of different types of cells like bone cells, muscle cells, body cells, etc. Each type, consisting of millions of tiny cells, forms a single unit which has a specialized function. The duty of carrying electrical messages from one part of the body to the other has been assigned to nerve cells. Our nervous system is made up of these nerve cells. A nerve cell with all its branches is called a neuron. This neuron is the ultimate structure and functional unit of the nervous system. The number of these neurons in a human nervous system has been estimated at 100 to 200 billion. They are basically alike in structure but appear in different lengths, sizes and shapes designed for specialized functions. Within each neuron there are millions of RNA molecules, each carrying genetic instructions from the DNA.

Miya oq va kul rang moddadan iborat. Kul rang modda asab hujayralarining to‘plamlaridan hosil bo‘ladi, oq moddani esa asab tolalari tashkil etadi. yAqin vaqtgacha kul rang modda asosan yurish va yugurishga bo‘lgan ko‘nikma hosil qilish bilan bog‘lanar edi. Hozirgi kunlarda olimlar yana bir qonuniyatni aniqladilar-yangi raqs harakatlarini o‘rganib, ijro etishga layoqatli insonlarning miyasi faolroq bo‘lar ekan.

Miya yarim sharlarining vazifalarini ko‘rgazmali tarzda quyidagicha tasvirlash mumkin ( 4.1 jadval).

4.1 Jadval