Question

You discover an unusual new organism in the deep sea and are studying its skeletal system in a laboratory aquarium. The organism appears to have a radial body plan with a center fluid-filled cavity. If you remove fluid from its interior using a syringe, it seems to collapse somewhat. What kind of skeletal system does this organism likely have?

a) Endoskeleton
b) Exoskeleton
c) Hydrostatic skeleton
d) Axial skeleton

Answer 1

The deep sea organism likely has a hydrostatic skeleton, as evident by the fluid-filled cavity that collapses when fluid is removed.

Step-by-step explanation:

The skeletal system of the newly discovered deep sea organism is likely a hydrostatic skeleton. This type of skeleton is characterized by a fluid-filled cavity known as the coelom, which supports the body and helps maintain its shape under pressure. The observation that the organism collapses somewhat when fluid is removed supports this identification, as the coelom's fluid is responsible for the hydrostatic pressure that keeps the organism's structure intact. Hydrostatic skeletons are common in soft-bodied animals, such as sea anemones and earthworms, which move by peristaltic muscle contraction affecting the shape and pressure of the coelom.