The Sea Slug Pteraeolidia Ianthina Can Harbour Living Dinoflagellates (Photosynthetic

question 52

Multiple Choice

The sea slug Pteraeolidia ianthina can harbour living dinoflagellates (photosynthetic protists) in its skin. These endosymbiotic dinoflagellates reproduce quickly enough to maintain their populations. Low populations do not affect the sea slugs very much, but high populations (> 5 × 105 cells/mg of sea slug protein) can promote sea slug survival.
Percent of sea slug respiratory carbon demand provided by indwelling dinoflagellates.
-In the graph, the percent of the oxygen demand contributed by the dinoflagellates is greater than 100% during much of the year. What is the fate of this "excess" energy?

• A) It is dispersed as "entropy" (disorder in the system).
• B) It is saved for producing offspring by the sea slug.
• C) It is used to move around the sea bottom.
• D) It is used in evaporative cooling by the sea slug.

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Definitions:

Joint Cavity

The space between the articulating bones of a joint, filled with synovial fluid that lubricates and nourishes the joint.

Amphiarthroses

A type of joint in the body that allows for limited movement, as found between vertebrae.

Synarthrotic Joints

A type of joint that allows for little or no movement, typically found where bones are fused together, such as in the skull.

Synovial Joints

Freely movable joints in the body, characterized by a cavity filled with synovial fluid, which lubricates and nourishes the joint.