Tag: nutrient cycles- flow of substances

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Questions Related to nutrient cycles- flow of substances

Multiple choice zoology bio-geo chemical cycles in nature nutrient cycles- flow of substances carbon cycle biogeochemical cycles - gaseous

The wormicide character of _____ destroys worms in water.

  1. Azotobacter

  2. Azolla

  3. Nostoc

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The wormicide character that kills worms in water are Azotobactor.
Azotobactors are one of the Nitrogen-fixing bacteria. Hence they are used as bio-fertilisers for many plants. 
The size of Azotobactor varies from 1-20 μm in length and 1-2 μm. 
Azotobactors can be generally found in alkaline soil and aquatic regions. So, the correct answer is A.
Multiple choice zoology bio-geo chemical cycles in nature nutrient cycles- flow of substances carbon cycle biogeochemical cycles - gaseous

Which bacteria is responsible to fix nitrogen in leguminous plants?

  1. Azotobacter

  2. Rhizobium

  3. Clostridium

  4. Saccharomycese
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Some bacteria maintain the soil fertility and others enhance it. The fertility of the soil is proportional to the nitrogen content. Nitrogen is an important ingredient in the structure and function of the living beings. Nitrogen-fixing bacteria like Azotobacter, Clostridium live free in the soil and fix atmospheric nitrogen. Rhizobium like bacteria live symbiotically with root systems of leguminous plants and fix from the atmospheric nitrogen. Therefore, the correct answer is option B.

Multiple choice zoology bio-geo chemical cycles in nature nutrient cycles- flow of substances carbon cycle biogeochemical cycles - gaseous

The microbial biofertilizers which can act both symbiotically and non-symbiotically to increases soil fertility are

  1. Azotobacter

  2. Rhizobium

  3. Clostridium

  4. `Nostoc and Anabaena
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Azotobacter can act both as symbiotically and non symbiotically to increase soil fertility. It Infuse the soil with antibiotic pesticides and inhabit the spread of soil borne diseases like pythium and phytophthora.

Multiple choice zoology bio-geo chemical cycles in nature nutrient cycles- flow of substances carbon cycle biogeochemical cycles - gaseous

Some of the nutrient cycles are labelled as below. Sulphur
cycle (A), phosphorus cycle (B), carbon cycle (C) and
nitrogen cycle (D)
Of these, the sedimentary cycle is represented by

  1. (A) only

  2. (B) only

  3. (C) only

  4. (A) and (B) only

  5. (C) and (D) only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sedimentary cycles involve elements that spend most of their time in the Earth's crust. Both the sulphur and phosphorus cycles are classified as sedimentary cycles, as their main reservoirs are rocks and soil.

Multiple choice zoology bio-geo chemical cycles in nature nutrient cycles- flow of substances carbon cycle biogeochemical cycles - gaseous

The bacterium nitrobacter converts

  1. Nitrogen to nitrite

  2. Ammonia to nitrite

  3. Nitrite to nitrate

  4. Nitrate to nitrite
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Nitrification is a two step process of converting ammonia into nitrites and nitrites into nitrates. Bacteria converting ammonia into nitrites includes Nitrosomonas. Bacteria converting nitrites to nitrates includes Nitrobacter.

Thus, the correct answer is 'Nitrite to nitrate.'