Describe trophic levels and energy flow — Hinglish notes

5.1.5 · Biology › Ecology & Ecosystems

Trophic level KIYA hota hai?

Level	Naam	Example	Role
1	Producers (autotrophs)	grass, algae	photosynthesis ke zariye food banate hain
2	Primary consumers (herbivores)	grasshopper	producers ko khaate hain
3	Secondary consumers (carnivores)	frog	primary consumers ko khaate hain
4	Tertiary consumers	snake	secondary consumers ko khaate hain
—	Decomposers	bacteria, fungi	dead matter ko break down karte hain, nutrients recycle karte hain

Energy flow KYUN karti hai (aur sirf ek hi direction mein kyun)?

Yeh sirf laws of thermodynamics ka biology mein application hai:

1st law: energy conserved hoti hai — kuch bhi gayab nahi hota, form badal jaata hai.
2nd law: har transfer mein kuch usable energy heat ke roop mein waste hoti hai — isliye kisi level par hamesha usable energy kam hoti hai neeche wale level se.

KITNI energy lost hoti hai? — 10% rule ko first principles se derive karna

Hum sirf "10%" yaad nahi karenge. Isko build karte hain.

Maano ek trophic level ko per unit area per time $E_{n}$ energy milti hai (units: $kJ m^{- 2} yr^{- 1}$ ). Iska kya hota hai?

$E_{n} = respiration (heat) R + egested/not eaten E_{eg} + stored as new biomass P$

Sirf stored biomass $P$ hi next level dwara khaaya ja sakta hai. Isliye:

$E_{n + 1} = P = E_{n} - R - E_{eg}$

Ecological (transfer) efficiency define karte hain:

Kyunki yeh har step par multiply hota hai, producers $E_{1}$ se shuru karke $n$ transfers ke baad energy hogi:

$E_{n} = E_{1} \times (0.10)^{n - 1}$

Consequence: energy pyramids aur choti chains

Figure — Describe trophic levels and energy flow

Common mistakes (steel-manned)

Flashcards

Trophic level kiya hota hai?

Food chain mein organism ki position — Sun se kitne energy-transfer steps door hai.

Producers kaun se trophic level par hote hain?

Level 1 (autotrophs, e.g. plants/algae, photosynthesis se food banate hain).

Energy one-way kyun flow karti hai jabki nutrients cycle karte hain?

Energy har step par heat ke roop mein lost hoti hai (2nd law) aur dobara khayi nahi ja sakti; matter ke atoms kabhi destroy nahi hote isliye recycle hote hain.

Ecological efficiency ki equation batao.

Efficiency = energy passed on / energy received = E(n+1)/E(n), roughly 0.10.

Roughly kitna fraction energy next trophic level tak jaati hai?

Lagbhag 10%.

~90% lost energy kahan jaati hai?

Respiration (heat), plus egested/uneaten parts (faeces, bones, roots) aur non-predation se death.

Food chains usually sirf 4–5 links kyun hoti hain?

Energy har level par ~10× shrink hoti hai, isliye kuch steps ke baad itni kam bachti hai ki koi aur population support na ho sake.

Energy ka pyramid HAMESHA upright kyun hota hai?

Har level mein neeche wale ka ~10% hota hai, isliye bars upar jaate jaate shrink hote hain.

Producers E1 se nth level par energy ka formula batao.

E(n) = E1 × (0.10)^(n-1).

Plants khaana meat khaane se zyaada energy-efficient kyun hai?

Kam 10% transfer steps hote hain, isliye khane ke har kJ ke liye kam energy waste hoti hai.

Decomposers energy flow mein kiya role play karte hain?

Yeh sab levels ke dead matter/faeces ko break down karte hain, energy heat ke roop mein release karte hain aur nutrients recycle karte hain.

Recall Feynman: 12-saal ke bacche ko explain karo

Socho Sun ne grass ko 100 coins ka ek bada bag diya. Grass zyaadatar apne paas rakhti hai aur sirf 10 coins us rabbit ko deti hai jo use khaata hai. Rabbit sirf 1 coin fox ko deta hai. Fox ke paas dene ke liye almost kuch bhi nahi bachta — isliye upar bahut saare foxes nahi hote, aur food chains choti hoti hain. Coins (energy) body heat ke roop mein "spend" ho jaate hain aur kabhi waapis nahi aate, isliye Sun ko har roz naye coins bhejte rehna padta hai.

Connections

Food chains and food webs
Photosynthesis — producers light energy kaise capture karte hain
Cellular respiration — heat loss kahan se aati hai
Ecological pyramids (number, biomass, energy)
Nutrient cycles (carbon, nitrogen) — woh matter jo cycle karta hai
Laws of thermodynamics
Biomagnification — chains ka choti hona toxins ke liye kyun matter karta hai