Which Statement About Speciation Is True

question 16

Multiple Choice

Which statement about speciation is true?

• A) Evolutionary changes to an organism always result in a species.
• B) A single lineage always splits to form species after a few generations.
• C) Speciation relies on gene flow.
• D) Genetic changes preventing reproduction between formerly interbreeding populations can lead to speciation.
• E) Only the biological species concept is concerned with reproductive isolation.

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Definitions:

Chargaff's Rules

Empirical rules stating that DNA from any cell of any organisms has a 1:1 ratio of pyrimidine and purine bases (cytosine to guanine and adenine to thymine).

Purines

Nitrogenous bases found in DNA and RNA that include adenine and guanine.

Pyrimidines

One of the two types of nitrogenous bases found in nucleic acids, characterized by a single ring structure, and includes cytosine, thymine (DNA only), and uracil (RNA only).

Semiconservative Replication

The process by which DNA duplicates itself, where each new DNA molecule consists of one old strand and one newly synthesized strand.