Question

What is/are the energy source(s) utilized by primary producers in the hydrothermal vents on the ocean floor?

(a) light

(b) sulfur compounds

(c) organic molecules

(d) carbon dioxide

Answer 1

In Hydro-thermal vents on ocean floor chemo-synthetic bacteria are the primary producers, they oxidize hydrogen sulfide present in the vent water to get energy, which helps them in producing organic material. Which is used by other higher organisms.

Here in the question option-A says light, in deep ocean though light is absent, but some bacteria like green sulfur bacteria are able to grow in much lower light intensities, they have chlorosomes which help them in capturing light from weak radioactive glow emitted from Geo-thermally heated rocks. So this can be a source of energy for the primary producers like green sulfur bacteria which requires chemical energy as well as light energy for its survival.

Option-b says sulfur compounds, this is the correct option as in deep sea vent the water coming out of the vent contains sulfur compounds, which is used by the primary producers as a source of energy.

Option-c it says organic molecules- this cannot be the correct option as organic molecules are the products of primary producers they cannot be source of energy.

Option-D says carbon-dioxide, this cannot be the correct answer because it is fixed for its fixation usually energy is obtained from hydrogen and sulfur compounds.

So option-A, B are the correct answer. Option-B is the most important source of energy used by the primary producers in hydro-thermal vents on the ocean floor.