Ichthyosaurs Were Aquatic Dinosaurs

question 21

Multiple Choice

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are

• A) homologous.
• B) examples of convergent evolution.
• C) adaptations to a common environment.
• D) Three of the responses above are correct.
• E) Two of the responses above are correct.

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Definitions:

Electroconvulsive Therapy (ECT)

A medical treatment most commonly used for severe depression, involving the induction of seizures in patients under anesthesia through the application of electrical currents to the brain.

Major Depressive Disorder

A severe pattern of unipolar depression that is disabling and is not caused by such factors as drugs or a general medical condition.

Nutraceuticals

Products derived from food sources with extra health benefits in addition to their basic nutritional value.

Conventional Treatments

Traditional or mainstream medical treatments widely accepted and practiced by the medical community.