At the End of the Paleozoic Era,all

question 66

Multiple Choice

At the end of the Paleozoic era,all

• A)dinosaurs became extinct.
• B)flowering plants grew to great heights.
• C)fish species became extinct.
• D)trilobites became extinct.

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Definitions:

Pyrimidine

A nitrogen-containing heterocyclic aromatic compound, similar to benzene and pyridine, but with two nitrogen atoms in the ring.

Aromatic

Refers to organic compounds containing one or more benzene rings or similar ring structures, characterized by their stability and unique chemical properties.

Antiaromatic

Compounds that have conjugated pi systems but do not obey Huckel's rule, leading to instability.

Nonaromatic

A term describing organic compounds that do not contain a conjugated system of pi electrons in a ring, thus not meeting the criteria for aromaticity.