alleryDownstream of a sewage outlet, fish die because microbes consume the:
ADissolved oxygen
BDissolved salts
CIncoming sunlight
DRiver bed sand
Answer & Solution
Correct answer: A. Dissolved oxygen
1. Microbes multiply on the organic matter.
2. They use up oxygen as they work.
3. Dissolved oxygen falls sharply and fish die.
_Source: syllabus Biology, Chapter 16, Environmental Issues._
Keep practising Biodiversity and Conservation
Browse all Biodiversity and Conservation questions for CBSE Class 12 (Science), or explore more Biology topics.
Related questions
To qualify as a hotspot, a region must have lost at least what share of its primary vegetaWho wrote about the biodiversity hotspot concept in 1988 and 1990?The 2002 World Summit on Sustainable Development was held in which city?The Convention on Biological Diversity (Earth Summit) was held where in 1992?Seeds of different genetic strains of crop plants are kept in what?Preserving gametes of threatened species for long periods uses which technique?Which is an ex situ conservation site?Sacred groves in Meghalaya are found in which hills?