In chemical formulas of functional groups, the symbol $$R$$ represents a 'residue,' which denotes the remainder of the molecule. This residue can be a single hydrogen atom or a complex group containing many atoms.

Residue in Chemical Formulas

A carbonyl group is a functional group consisting of a carbon atom double-bonded to an oxygen atom ($$C=O$$). It is present in several classes of organic compounds, either as a standalone group or as a component of larger functional groups like ketones, aldehydes, carboxylic acids, and amides.

Carbonyl Group

Ketones are a class of organic compounds containing a carbonyl group ($$C=O$$) that is located at an internal position within the carbon chain of the molecule.

Ketones

Aldehydes are a class of organic compounds containing a carbonyl group ($$C=O$$) that is located at the terminal position (end) of the carbon chain.

Aldehydes

Functional groups are specific groups of atoms within biomolecules that are characterized by their particular chemical composition and the chemical reactions they perform, regardless of the larger molecule containing them. These groups can range in complexity from one or two atoms to combinations of multiple simpler functional groups.

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Is an organic molecule that  is found within living organisms they are the building blocks of life and contain chemicals that are composed of oxygen, carbon, hydrogen, sulfur, nitrogen, and phosphorus.

Biomolecule

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Microbiology covers the scope and sequence requirements for a single-semester microbiology course for non-majors. The book presents the core concepts of microbiology with a focus on applications for careers in allied health. The pedagogical features of the text make the material interesting and accessible while maintaining the career-application focus and scientific rigor inherent in the subject matter. Microbiology’s art program enhances students’ understanding of concepts through clear and effective illustrations, diagrams, and photographs.

Microbiology is produced through a collaborative publishing agreement between OpenStax and the American Society for Microbiology Press. The book aligns with the curriculum guidelines of the American Society for Microbiology.

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Biomolecules contain a carbon sekelton which is a result of carbon’s unique combination of size and bonding properties, carbon atoms can bind together in large numbers, thus producing a chain. The carbon skeleton of organic molecules can be straight, branched, or ring shaped (cyclic).

Carbon skeleton

Organic molecules are carbon-containing compounds whose structures are typically built around carbon atom chains. Unlike inorganic molecules, they must contain carbon atoms covalently bonded to hydrogen atoms.

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