Is there photosynthetic activity in the benthic zone of the ocean?

No photosynthetic activity is witnessed in the benthic zone.

A common lake has three zones of organic networks connected to its physical structure. The littoral zone is the close to shore region where daylight infiltrates right to the residue and permits sea-going plants (macrophytes) to develop. The 1 % light level characterizes the euphotic zone of the lake, which is the layer from the surface to the profundity where light levels become unreasonably low for photosynthesis.  

The innermost territory is the benthic zone, filled by fine layers of mud in which only animals live. Due to the absence of plants as well as no penetration of light in this zone, no photosynthetic activity is seen.

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