BiologyBhanu · Class 4-5
Dil, naseein aur khoon ka safar
Khoon dil se nikal ke kahan jaata hai, aur wapas kaise aata hai?
Socho pehle… phir dekho jawab
Khoon dil se naseein (blood vessels) ke through poore sharir mein jaata hai, oxygen aur khaana pahunchata hai, aur wapas dil mein aata hai — yeh ek chakkar hai, isliye ise 'circulation' kehte hain.
Dil do taraf kaam karta hai: ek taraf se khoon phephdon (lungs) ko jaata hai jahan usme oxygen milta hai, doosri taraf se yeh oxygen-bhara khoon poore sharir mein jaata hai.
Cause-effect: jitna zyada kaam (daudna, khelna), utna zyada oxygen chahiye muscles ko, isliye dil tez dhadakta hai aur zyada khoon bhejta hai.
Naseein do tarah ki hoti hain: jo khoon dil se le jaati hain, aur jo khoon dil tak wapas laati hain. Dono milke ek lambi trip banati hain.
Ghar pe try karo
Apni kalai (wrist) par do ungli halke se rakho, thodi der dhoondo — dhak-dhak jaisi halki dhadkan (pulse) mehsoos hogi. Ab thoda daudo aur dobara check karo.
Wow!
Agar tumhari saari naseein ko seedhi line mein laga do, toh woh hazaron kilometre lambi ban jaayengi!
Mummy-Papa ke liye
Aaj bachche ke saath kalai par pulse dhoondwaiye, phir thoda daudwa ke dobara check karwaiye.
3 sawaal
- Khoon ko oxygen kahan se milta hai?
Jawab dekho
Phephdon se. Khoon phephdon mein jaata hai aur wahan se oxygen leta hai.
- Daudne se dhadkan par kya asar hota hai?
Jawab dekho
Tez ho jaati hai. Zyada kaam mein zyada oxygen chahiye, isliye dhadkan tez hoti hai.
- Naseein kya kaam karti hain?
Jawab dekho
Khoon ko aage-peeche le jaati hain. Naseein khoon ko dil se le jaati aur dil tak wapas laati hain.
NCERT se jodo: NCERT Class 5 EVS (Looking Around) — hamara sharir aur uske ang