The Peking Man Fossils from Zhoukoudian Date from Around __________

question 20

Multiple Choice

The Peking Man fossils from Zhoukoudian date from around __________ years ago.

• A) 600,000 to 200,000
• B) 6 million to 2 million
• C) 6,000 to 2,500
• D) 6 million to 250,000

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Definitions:

Enantiomers

Stereoisomers that are mirror images of each other but cannot be superimposed, differing in the configuration around one or more chiral centers.

Phantasmidine

A chemical compound naturally occurring in some amphibian species, known for its bioactive properties.

Chiral Center

A carbon atom that is attached to four different groups, making its mirror images non-superimposable.

Stereoisomer

Molecules that have the same molecular formula and sequence of bonded atoms but differ in the three-dimensional orientations of their atoms in space.