The Following Questions Refer to the Paragraph Below

question 11

Multiple Choice

The following questions refer to the paragraph below.
An elementary school science teacher decided to liven up the classroom with a salt-water aquarium. Knowing that salt-water aquaria can be quite a hassle, the teacher proceeded stepwise. First, the teacher conditioned the water. Next, the teacher decided to stock the tank with various marine invertebrates, including a polychaete, a siliceous sponge, several bivalves, a shrimp, several sea anemones of different types, a colonial hydra, a few coral species, an ectoproct, a sea star, and several gastropod varieties. Lastly, some vertebrates-a parrotfish and a clownfish-were added. She arranged for daily feedings of copepods and feeder fish.
-The clownfish readily swims among the tentacles of the sea anemones; the parrotfish avoids them. One hypothesis for the clownfish's apparent immunity is that they slowly build a tolerance to the sea anemone's toxin. A second hypothesis is that a chemical in the mucus that coats the clownfish prevents the nematocysts from being triggered. Which of these findings would lend the greatest support to the second hypothesis?

• A)Upon close examination, clownfish maneuverability is so precise as to allow it to avoid contacting any tentacles.
• B)Clownfishes can eat the dead tentacles of the sea anemones.
• C)Clownfishes are immune to the toxins of not just one, but many species of sea anemone.
• D)Clownfish mucus contains a chemical very similar to one found in the trigger mechanism of sea anemone nematocysts.

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Definitions:

Thymus

A small organ located in the upper chest, crucial for the development of the immune system's T cells during early life.

Lymph Nodes

Small, bean-shaped structures that are part of the body’s immune system, trapping pathogens and foreign particles.

Tonsils

Masses of lymphoid tissue located at the back of the throat that help protect the body from infection and play a role in the immune system.

Antigenic Determinants

Specific parts of a molecule that are recognized by the immune system, critical for the specificity of immune responses.