Question

Most animals that live in deep oceanic water are
A) Primary consumers
B) Secondary consumers
C) Tertiary consumers
D) Detritivores

Answer 1

Hint: Benthos is the community of organisms that live in, or on the seabed. This living area is also called benthic zones. They are deep oceanic water organisms. They do not need any lights. Most organisms of the benthos are from detritivores. Some detritivores and benthos share a common niche.

Complete answer:
As we know, no light is present in this zone of sea, the energy source for the deep benthic ecosystem is often organic matter from a higher water column which drifts down to the depths. This dead and decaying matter undergoes the benthic organisms, and hence, most of the organisms in the benthic zone (deep oceanic waters), are scavengers or detritivores.
A) Primary consumers - Primary consumers are herbivores that ingest the producers. It is also an incorrect option.
B) Secondary consumers - they eat primary consumers. So this is the wrong option
C) Tertiary consumers – they eat secondary consumers. So this is the wrong option.
D) Detritivores - Detritivores are organisms that derive their nutrition from the organic waste of dead and decaying plants and animals. They occupy the topmost position in the food chain.

The correct answer is (D) – Detritivores.

Note:
> The earthly detritivores are butterflies, beetles, snails, and slugs. The detritivores in the aquatic ecosystem are lobsters, crabs, and sea stars, etc.
> They break down the dead and decaying matter, thereby, helping in recycling nutrients.
> Detritivores such as earthworms that live in soil, aerate the soil and help in plant growth.
> They help in the removal of dead matter and prevent the spread of diseases.