A sea anemone has radial symmetry;its touch receptors and eye spots are located all around its circular body.A deer has large eyes and ears and a sensitive nose,all of which are clustered at the head end of its body.Which difference in these two organisms most likely accounts for this difference in the location of sensory organs?
A) The sea anemone lives in water;the deer lives on land.
B) The sea anemone is a predator;the deer is a prey animal.
C) The sea anemone is simple in structure;the deer is complex.
D) The sea anemone is sessile;the deer moves forward into its environment.
E) The sea anemone has tentacles;thus,it has no need for cephalization of sensory organs.

Question

Quizplus · Accepted Answer

The location of sensory organs in an organism partly depends on its mode of life. A sessile organism like a sea anemone has no means of moving towards stimuli and hence sensory receptors need to be distributed evenly on its body surface. In contrast, a mobile organism like a deer can move around to find food, avoid danger or search for a mate. Therefore, sensory organs are concentrated at the front end of the body to receive information from the direction of travel.

A Sea Anemone Has Radial Symmetry;its Touch Receptors and Eye