NCERT Formulas Class 10 Science Chapter 13 – Our Environment
NCERT Science • Class 10

Our Environment

Biological Ratios & Ecological Pathways

📊 The 10% Law of Energy Flow

Lindeman’s Law states that only 10% of energy is transferred to the next trophic level.

↔ Swipe to view energy calculation
$$\text{Energy Available at Next Level} = \text{Energy at Current Level} \times 0.10$$
Example:

Plants ($1000 \text{ J}$) $\rightarrow$ Herbivore ($100 \text{ J}$) $\rightarrow$ Carnivore ($10 \text{ J}$)

🛡️ Ozone Layer Formation

Ozone ($O_3$) is formed at higher levels of the atmosphere by the action of UV radiation on Oxygen.

$$O_2 \xrightarrow{\text{UV Radiation}} O + O$$ $$O + O_2 \rightarrow O_3 (\text{Ozone})$$
📈 Biological Magnification

The increase in concentration of harmful chemicals (like pesticides) at each higher trophic level.

$$\text{Chemical Concentration: } \text{Producers} < \text{Herbivores} < \text{Carnivores} < \text{Top Predator}$$

Result: Human beings often have the highest concentration of toxins.

[Image of biological magnification in a food chain]
🌿 Ecosystem Components

Biotic Factors: Producers, Consumers, Decomposers

Abiotic Factors: Temperature, Rainfall, Wind, Soil, Minerals


$$\text{Ecosystem} = \text{Biotic Community} + \text{Abiotic Environment}$$
♻️ Biodegradability Logic

Biodegradable: Broken down by biological processes (Bacteria/Fungi).

Non-biodegradable: Cannot be broken down (Plastics, DDT).

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