Pharyngeal Slits Are Present in the Embryos of Organisms as Diverse

question 27

Multiple Choice

Pharyngeal slits are present in the embryos of organisms as diverse as fish,chickens,and humans.Why would organisms as different as these have similar embryonic structures?

• A)The organisms shared a common ancestor whose embryos had pharyngeal slits.
• B)The pharyngeal slits is an acquired characteristic that just happens to look similar in different species.
• C)The organisms shared a common ancestor, which did not have the slits, but natural selection created similar changes in the embryos over time.
• D)The pharyngeal slits develop into gills because all species need to survive in a water environment at some point in their life cycle.

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Definitions:

Isoelectric Point

The pH at which a molecule carries no net electrical charge, crucial for predicting molecule behavior in different environments.

Amino Acids

Organic compounds that serve as the building blocks of proteins, each containing an amino group (-NH2), a carboxyl group (-COOH), and a distinctive side chain.

Activated Acyl Derivative

A highly reactive form of an acyl compound used in chemical synthesis, often prepared to facilitate nucleophilic attack for the formation of amides, esters, and other functionalities.

N,N'-Dicyclohexylcarbodiimide

A chemical compound used as a dehydrating agent in peptide synthesis and other organic synthesis processes.