Use the Information and Figure to Answer the Following Question

question 27

Multiple Choice

Use the information and figure to answer the following question.
The sea slug Pteraeolidia ianthina can harbor 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.
If the dinoflagellate-containing sea slug P. ianthina preys on coral animals, then it would be most surprising to find that ________.

• A) P. ianthina can tolerate the toxin in the nematocysts of its prey
• B) P. ianthina can locate its coral prey by chemicals released into the water by corals
• C) the coral prey harbor dinoflagellates in their tissues
• D) the coral prey transform themselves into medusas to flee from approaching P. ianthina

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Definitions:

Dendrites

Root-like parts of neurons that receive impulses from other neurons.

Neurons

The basic working units of the brain, specialized cells that transmit information through electrical and chemical signals.

Axon terminals

The endings of axons, responsible for transmitting signals through neurotransmitters to other neurons or muscles.

Neurotransmitters

Chemical messengers that transmit signals across a chemical synapse, from one neuron (nerve cell) to another target neuron, muscle cell, or gland cell.