The Leg Bones of the First Tetrapod (Shown in the Diagram

question 99

Multiple Choice

The leg bones of the first tetrapod (shown in the diagram below) are hypothesized to have evolved from bones in the

• A)legs of an amphibian.
• B)wings of a bird.
• C)fins of an aquatic mammal.
• D)fins of a fish.

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Definitions:

LUMO

The Lowest Unoccupied Molecular Orbital, which is the first molecular orbital available for the electron to occupy.

Cycloaddition

A type of chemical reaction where two or more unsaturated molecules combine to form a cyclic adduct, important in the synthesis of heterocyclic compounds.

Organic Letters

A peer-reviewed scientific journal publishing original research articles in organic chemistry.

Molecular Orbitals

Orbitals that belong to a molecule as a whole, where electrons are considered to be delocalized over the entire molecule.