Shareer Ki Taar Ki Jaali ⚡
Nervous system ki basic ikai hai neuron — shareer ki sabse lambi cell. Ek neuron kamar se pair ke angoothe tak, lagbhag 1 metre lamba ho sakta hai!
📌 Neuron ke hisse:
🌿 Dendrites — sandesh lete hain (information IN)
⚪ Cell body (soma) — sandesh yahan ikattha hota hai
🔌 Axon — sandesh door le jaata hai (information OUT)
🔚 Axon terminals — agle cell ko sandesh dete hain
📨 Sandesh Ka Safar
1️⃣ Dendrite par: uddipan se ek rasayanik badlav hota hai, jo
bijli ka signal (impulse) ban jaata hai.
2️⃣ Axon par: ye bijli ka signal tezi se aage daudta hai.
3️⃣ Axon ke sire par: signal ek rasayan (chemical) chhodta hai.
4️⃣ Synapse paar karke: wo rasayan agle neuron ke dendrite par pahunchta hai aur wahan
dobara bijli ban jaata hai.
📌 Synapse: Do neurons ke beech ki bahut chhoti khaali jagah. Yahan signal
bijli → rasayan → bijli mein badalta hai.
💡 Faayda: Synapse ki wajah se signal sirf EK DISHA mein jaata hai —
wapas nahi aa sakta. Isiliye sandesh mein gadbad nahi hoti.
Nerve impulse lagbhag 100 metre per second tak ki raftaar se chal sakta hai — yani 360 km/h! Isiliye chot lagte hi turant dard mehsoos hota hai. Par ye phir bhi bijli ke taar (30 crore m/s) se bahut dheema hai — kyunki ye asli bijli nahi, rasayanik-bijli hai.
🗺️ Nervous System Ke Hisse
| Hissa | Kya shaamil | Kaam |
|---|---|---|
| CNS (Central) | Dimaag + Spinal cord | Sochna, faisla lena, control |
| PNS (Peripheral) | Saari nerves | CNS ko shareer se jodna |
| Nerve ka prakar | Sandesh kis taraf |
|---|---|
| Sensory (gyanvahi) | Receptor → CNS (andar laati hai) |
| Motor (prerak) | CNS → Muscle/gland (bahar le jaati hai) |
| Mixed | Dono kaam |
🧠 Yaad rakhne ki trick: Sensory = Sandesh andar laati hai. Motor = Muscle ko bhejti hai.
⚠️ Nervous system ki suraksha: Dimaag ko khopdi (skull) aur spinal cord ko reedh ki haddi bachati hai, aur dono ke beech tarl (CSF) gadde ka kaam karta hai. Isiliye cycle/bike chalate waqt helmet pehnna zaroori hai — ek chot poori zindagi badal sakti hai.
🧠 Apne Aap Ko Test Karo
⚡ Reflex Arc simulator mein poora raasta chalte hue dekho!
Open Reflex Simulator →