This Photograph Shows Chert

question 93

Multiple Choice

This photograph shows chert. How does it form?

• A) evaporation of water in a lake or sea
• B) accumulation of microscopic organisms composed of calcium carbonate
• C) precipitation from seawater early in Earth's history
• D) accumulation of silica-rich organisms or mixing of seawater and groundwater

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Definitions:

Interbreeding Populations

Groups of the same species that are capable of reproducing together, sharing a common gene pool.

Reproductive Isolation

A collection of mechanisms, behaviors, and physiological processes that prevent the members of two different species from producing offspring, or ensure that any offspring are sterile.

Speciation

Emergence of a new species.