Lead concentration in blood is considered alarming, if it is:
20ug/100mL
30ug /100mL
4-6 ug / 100mL
10 ug / 100mL
The greatest biomass of autotrophs in the world's oceans is that of
benthic brown algae , coastal red algae and daphnids.
benthic diatoms and marine viruses
sea grasses and slime molds
free-floating micro-algae , cyanobacteria and nanoplankton
The slow rate of decomposition of fallen logs in nature is due to their:
Low moisture content
Poor nitrogen content
Anaerobic environment around them
Low cellulose content
Species restricted to a given area are called
sibling
endermic
sympatric
allopatric
Which of the following ecosystem types has the highest annual net primary productivity ?
Tropical rain forest
Tropical deciduous forest
Temperate evergreen forest
Temperate deciduous forest
Annual migration does not occur in the case of:
Salmon
Siberian crane
Salamander
Arctic tern
What is true for individuals of same species ?
Live in same niche
Live in same habitat
Interbreeding
Live in different habitats
What is a keystone species?
A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival.
A common species that has plenty of biomass, yet has a fairly low impact on the community's organization.
A rare species that has minimal impact on the biomass and on other species in the community.
A dominant species that constitutes a large proportion of the biomass and which affects many other species.
Which of the following is expected to have the highest value (gm/m2.yr) in a grassland ecosystem ?
Secondary Production (SP)
Tertiary Production (TP)
Gross Production (GP)
Net Production ( NP)
According to Central Pollution Control Board (CPCB), which particulate size in diameter (in micrometers) of the air pollutants is responsible for greatest harm to human health ?
2.5 or less
1.5 or less
1.0 or less
5.2 or 2.5
