We do not clean natural ponds or lakes, whereas an aquarium or a swimming pool needs to be cleaned regularly. Why?
We do not clean natural ponds or lakes, whereas an aquarium or a swimming pool needs to be cleaned regularly. Why?
Show Hint
Solution and Explanation
Natural ponds and lakes have a self-cleaning system where natural processes such as filtration, sedimentation, and biological processes help maintain water quality. However, aquariums and swimming pools are enclosed and do not have these natural processes, which is why they require regular cleaning and maintenance to prevent the accumulation of waste and maintain clean water.
Top Questions on Ecosystem
- (A) Analyse the following ecosystems and discuss, which will be more productive in terms of primary productivity:
A young forest, a natural old forest, a shallow polluted lake. - Differentiate between Net primary productivity and Gross primary productivity in an ecosystem.
- The process of mineralization by microorganisms helps in the release of:
- Why are restrictions imposed on MTP in India? Up to how many weeks or trimesters, is MTP considered relatively safe for a female, if necessary to perform, by a medical practitioner?
Read the passage given below and answer the question.
Food chains ‘P’ and ‘Q’ form an interconnection. ‘P’ initiates with wheat grass whose population supports a few grasshoppers, frogs and snakes.
‘Q’ starts with dead decaying leaves of wheat grass which are eaten by earthworms and then food chain is continued with frog of food chain ‘P’.
Identify the types of food chains ‘P’ and ‘Q’:
Questions Asked in CBSE X exam
- Find the zeroes of the polynomial: \[ q(x) = 8x^2 - 2x - 3 \] Hence, find a polynomial whose zeroes are 2 less than the zeroes of \(q(x)\)
- CBSE Class X - 2025
- Polynomials
- Find the smallest value of $p$ for which the quadratic equation $x^2 - 2(p + 1)x + p^2 = 0$ has real roots. Hence, find the roots of the equation so obtained.
- CBSE Class X - 2025
- Quadratic Equations
- Identify and correct the error in the sentence taken from the article – ‘The Hidden Health Risks of Bread Consumption’:
Health experts worldwide are concerning about the surge in health problems.
Error Correction- CBSE Class X - 2025
- Error Correction
- Describe the historical factors that contributed to the emergence of nationalist tensions in the Balkans.
- CBSE Class X - 2025
- The Rise of Nationalism in Europe
In the adjoining figure, \( AP = 1 \, \text{cm}, \ BP = 2 \, \text{cm}, \ AQ = 1.5 \, \text{cm}, \ AC = 4.5 \, \text{cm} \) Prove that \( \triangle APQ \sim \triangle ABC \).
Hence, find the length of \( PQ \), if \( BC = 3.6 \, \text{cm} \).
- CBSE Class X - 2025
- Triangles