Mass of living matter at a trophic level in an area at any time is called. 

• Detritus

• Humus

• Standing state

• Standing state

Which one of the following shows maximum genetic diversity in India? 

• Rice 

• Maize

• Mango

• Mango

A collection of plants and seeds having diverse alleles of all the genes of a crop is called

• germplasm

• gene library

• genome

• genome

Nitrifying bacteria

• convert free nitrogen to nitrogen compounds

• convert proteins into ammonia

• reduce nitrates to free nitrogen 

• reduce nitrates to free nitrogen 

Of the total incident solar radiation, the proportion of PAR is 

• about 60%

• less than 50%

• more than 80%

• more than 80%

Secondary sewage treatment is mainly a 

• mechanical process

• chemical process

• biological process

• biological process

Which one of the following is not a biofertilizer

• Rhizobium

• Nostoc

• Mycorrhiza

• Mycorrhiza

The most common substrate used in distilleries for the production of ethanol is 

• soya meal 

• ground gram

• molasses

• molasses

Ethanol is commercially produced through a particular species of 

• Clostridium

• Trichoderma

• Aspergillus

• Aspergillus

What will you look for to identify the sex of the following?

• male frog - a copulatory pad on the first digit of the hind limb

• Female cock - anal cerci

• Male shark - claspers borne on pelvic fins

• Male shark - claspers borne on pelvic fins