Use the Following Information to Answer the Question

question 83

Multiple Choice

Use the following information to answer the question.
An elementary school science teacher decided to liven up the classroom with a saltwater aquarium. Knowing that saltwater 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 herbivorous gastropod varieties. Lastly, she added some vertebrates-a parrot fish and a clown fish. She arranged for daily feedings of copepods and feeder fish.
Normally, the clown fish readily swims among the tentacles of the sea anemones; the parrot fish avoids them. One hypothesis for the clown fish'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 clown fish prevents the nematocysts from being triggered. Which of the following graphs supports the second, but not the first, of these hypotheses?

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Definitions:

Infant Mortality Rate

The statistical measure of the number of deaths of infants under one year of age per 1,000 live births in a given year.

Canada

A country in North America known for its vast landscapes, multicultural society, and as a member of the Commonwealth with a parliamentary democracy.

Illness

A condition that negatively affects a person's physical or mental health, often characterized by specific signs and symptoms.

Mortality

The state of being subject to death; often used in statistics to refer to the rate of death in a population.