Earth is an
Open system
Closed system
Both open and closed system
Neither A and B
Climate of the world is threatened by
Increasing concentration of atmospheric oxygen
Decreasing concentration of atmospheric oxygen
Increasing amount of atmospheric carbon dioxide
Decreasing amount of atmospheric carbon dioxide
Amount of carbon fixed annually through photosynthesis is
4.6 Χ 1010 kg
7 Χ 1013 kg
7 Χ 1020 kg
4.6 Χ 1021 kg
Component of biosphere related with soil is
Lithosphere
Hydrosphere
Atmosphere
None of the above
In one year, one hectare of forest shall
Consume 10 tonnes of CO2 and evolve 10 tonnes of O2
Consume 20 tonnes of CO2 and evolve 10 tonnes of O2
Consume 30 tonnes of CO2 and evolve 30 tonnes of O2
The combustion of fossil fuels and deforestation have caused the atmospheric concentration of carbon dioxide to increase by about 35% since the beginning of the age of industrialization. Hence consumption of carbon dioxide will increase every year.
Source of energy in the biosphere is
Producer
Decomposer
Sunlight
Heat of earth
A green house gas is
H2
CO
CO2
N2
Maintenance of soil fertility without addition of nutrition is due to
Floods
Crop residue
Favourable temperature
Microbial activity
A logical sequence of carbon cycle is
Producer-Consumer-Decomposer
Decomposer-Producer-Decomposer
Consumer-Producer-Consumer
Producer-Decomposer-Consumer
Green-house gases are
Absorbers of long-wave radiations from earth
Transparent to both solar radiations and long-wave radiations from earth
Absorbers of solar radiations for warming the atmosphere of earth
Transparent to emissions from earth for passage into outer space
