Home
Class 12
BIOLOGY
Assertion: The annual net primary produc...

Assertion: The annual net primary productivity of the whole biosphere is approximately 170 million tons (dry weight ) of organic matter.
Reason: Of this, despite occupying about 70 percent of the surface, the productivity of oceans are only 55 million tons.

A

If both assertion and reason are true and the reason is a correct explanation of the assertion.

B

If both assertion and reason are true but reason is not a correct explanation of the assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
D
`*` The annual net primary productivity of the whole biosphere is approximately 170 billion tons (dry weight) of organic matter.
`*` Of this, despite occupying about 70 percent of the surface, the productivity of oceans are only 55 billion tons.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ECOSYSTEM

    A2Z|Exercise Section C: (PREVIOUS YEARS' EXAMINATION QUESTIONS) NEET/AIMPT Questions|59 Videos

  • ECOSYSTEM

    A2Z|Exercise Section C: (PREVIOUS YEARS' EXAMINATION QUESTIONS) AIIMS Questions|11 Videos

  • ECOSYSTEM

    A2Z|Exercise Section A: Topicwise Questions (topic 7: Nutrient Cycling And Ecosystem Services) Carbon Cycle And P|21 Videos

  • BIOTECHNOLOGY: PRINCIPLES AND PROCESSES

    A2Z|Exercise Section D: Chapter-end Test|50 Videos

  • ENVIRONMENTAL ISSUES

    A2Z|Exercise Section D : Chapter-end Test|50 Videos

Similar Questions

Explore conceptually related problems

Assertion: Oceans are a low producitivy ecosystems despite occupying about 70% of the earth,s surface. Reason: In aquatic ecosystems, productivity water depth.

Dairy Farming is a major livelihood followed by many households in rural areas. This includes rearing milk cattle - cows, buffaloes , goats and sheep .There is a shortage of milk in the country as consumption in both urban and rural areas has risen sharphy. Dariying is an important source of subsidiary income to marginal farmers and agricultural labours. They play a very important role in milk production of the country. In 1986-87, about 73 percent of rural households owned livestock. Accordig to the National Sample Survey of 1993-94, livestock sector produces regular employment to about 9.8 million person in principal status and 8.6 million in subsidiary status, which constitute about 5 precent of the total workforce. The manure from animals provides a good source of organic matter from wells. The surplus fodder and agricultural by -products are gainfully utilized for feeding the animals. since agriculture is mostly seasonal, there is a possibility of finding employment throughout the year for many persons throught dairy farming. The milk processing industry is a samll one . Only 10 precent of all the milk produced is delivered to some 400 darily plants. A specific Indian phenomen is the unorganized sector of milkmen and vendors, which handles around 65-70 percent of the national milk production. They collect milk form local producers and sell it in both urban and non-urban areas. What is the main the of the extract ?

Knowledge Check

  • annual NPP of whole biosphere is approximately ______ tons (dry weight) of organic matter

    A
    170 millions
    B
    115 billion
    C
    55 billion
    D
    265 billion

  • Go through the following statements. A. Primary productivity of all ecosystem is a constant. B. The annual net primary productivity of the whole of the biosphere is 17 million tons (dry weight) of organic matter. C. Net primary productivity is the amount of biomass available for consumption by carnivores. D. . Secondary productivity is defined as the rate of formation of new organic matter by decomposers. E. Primary productivity depends on the plant species inhabiting a particular area. Which of the above statements about productivity is true?

    A
    A and B
    B
    B and C
    C
    C and D
    D
    Only E

  • The productivity of the oceans is approximately ....the annual net primary productivity of the whole biosphere .

    A
    half
    B
    one third
    C
    one fifth
    D
    one fourth

    • Similar Questions

    Explore conceptually related problems

    Dairy Farming is a major livelihood followed by many households in rural areas. This includes rearing milk cattle - cows, buffaloes , goats and sheep .There is a shortage of milk in the country as consumption in both urban and rural areas has risen sharphy. Dariying is an important source of subsidiary income to marginal farmers and agricultural labours. They play a very important role in milk production of the country. In 1986-87, about 73 percent of rural households owned livestock. Accordig to the National Sample Survey of 1993-94, livestock sector produces regular employment to about 9.8 million person in principal status and 8.6 million in subsidiary status, which constitute about 5 precent of the total workforce. The manure from animals provides a good source of organic matter from wells. The surplus fodder and agricultural by -products are gainfully utilized for feeding the animals. since agriculture is mostly seasonal, there is a possibility of finding employment throughout the year for many persons throught dairy farming. The milk processing industry is a samll one . Only 10 precent of all the milk produced is delivered to some 400 darily plants. A specific Indian phenomen is the unorganized sector of milkmen and vendors, which handles around 65-70 percent of the national milk production. They collect milk form local producers and sell it in both urban and non-urban areas. How is dairy farminy beneficial for farmers besides getting milk ?

    Dairy Farming is a major livelihood followed by many households in rural areas. This includes rearing milk cattle - cows, buffaloes , goats and sheep .There is a shortage of milk in the country as consumption in both urban and rural areas has risen sharphy. Dariying is an important source of subsidiary income to marginal farmers and agricultural labours. They play a very important role in milk production of the country. In 1986-87, about 73 percent of rural households owned livestock. Accordig to the National Sample Survey of 1993-94, livestock sector produces regular employment to about 9.8 million person in principal status and 8.6 million in subsidiary status, which constitute about 5 precent of the total workforce. The manure from animals provides a good source of organic matter from wells. The surplus fodder and agricultural by -products are gainfully utilized for feeding the animals. since agriculture is mostly seasonal, there is a possibility of finding employment throughout the year for many persons throught dairy farming. The milk processing industry is a samll one . Only 10 precent of all the milk produced is delivered to some 400 darily plants. A specific Indian phenomen is the unorganized sector of milkmen and vendors, which handles around 65-70 percent of the national milk production. They collect milk form local producers and sell it in both urban and non-urban areas. What infromation does the National Sample Survey of 1993-94 provide ?

    (A) : Primary productivity depends on the plant species inhabiting a particular area. (R) : The annual net primary productivity of our biosphere is about 170 billion tons of organic matter.

    Consider the following four statements (A-D) and select the correct option stating which ones are true (T) and which ones are False (F). (A) Vertical distribution of different species occupying different levels in a community is called stratification. (B) Net primary productivity minus respiration losses is the gross primary productivity. (C) Rate of biomass production is called decompostion. (D) Annual net primary productivity of oceans is 55 billion tons.

    Oceans occupy A percent of the earth surface and have a productivity of B percent of the productivity of the whole biosphere Choose the option which fits best for A & B in order

    Home
    Profile