topic a - biomolecules

Flashcards to review key concepts about biomolecules, including carbohydrates, lipids, proteins, and their structures, properties, and functions.

Carbohydrates

Main energy source and storage in cells.

Lipids

Main component of cell membrane and energy storage in cells.

Proteins

Serve structural and enzymatic functions in cells.

Nucleic acids

Store and transmit hereditary information.

Monosaccharides

Simple sugars that are the monomers making up disaccharides and polysaccharides.

Disaccharides

Carbohydrates composed of two monosaccharides linked by a glycosidic bond.

Polysaccharides

Large carbohydrates formed from many monosaccharides linked together.

Glycosidic bond

Bond formed between two monosaccharides through a condensation reaction.

Reducing sugar

A sugar that can donate electrons to reduce another compound. They contain either a free aldehyde or ketone group.

Benedict's test

A test used to detect the presence of reducing sugars, indicated by a color change from blue to green, yellow, orange, or red.

α-glucose and β-glucose

Isomers of glucose that differ in the position of the hydroxyl group on carbon-1.

Amylose

A linear polymer of glucose linked by α-1,4-glycosidic bonds, forming a helix.

Amylopectin

A branched polymer of glucose linked by α-1,4- and α-1,6-glycosidic bonds.

Glycogen

Main energy storage molecule in animals, similar to amylopectin but more branched.

Cellulose

A structural polysaccharide consisting of β-glucose monomers linked by β-1,4-glycosidic bonds.

Triglycerides

Lipids composed of three fatty acids and one glycerol molecule.

Ester bond

The bond formed between a glycerol molecule and a fatty acid in lipids.

Saturated fatty acids

Fatty acids containing only carbon-carbon single bonds in the hydrocarbon chain.

Unsaturated fatty acids

Fatty acids containing at least one carbon-carbon double bond in the hydrocarbon chain.

Phospholipids

Lipids containing a phosphate group, made up of 1 glycerol molecule, 2 fatty acid molecules and 1 phosphate group, forming bilayers in cell membranes.

Steroids

Lipids characterized by a carbon skeleton of four fused rings.

Amino acids

The monomers of proteins, containing an amino group, a carboxyl group, a hydrogen atom, and an R group bonded to a central carbon.

Peptide bond

The covalent bond between two amino acids, formed by a condensation reaction.

Primary structure

The specific sequence of amino acids in a polypeptide chain.

Secondary structure

Local spatial conformation of a polypeptide backbone, maintained by hydrogen bonds. Includes α-helices and β-pleated sheets.

α-helix

A coiled secondary structure of proteins, stabilized by hydrogen bonds between amino acids.

β-pleated sheet

A sheet-like secondary structure of proteins, held together by hydrogen bonds between adjacent polypeptide chains.

Tertiary structure

The overall three-dimensional shape of a polypeptide, stabilized by interactions between R groups.

Quaternary structure

The association of multiple polypeptide chains to form a functional protein complex.

Denaturation

The loss of a protein's specific three-dimensional conformation, leading to loss of function.

Haemoglobin

A globular protein in red blood cells responsible for transporting oxygen.

Collagen

A fibrous protein providing structural support in connective tissues.

G-protein linked receptor (GPLR)

A transmembrane protein involved in cell signaling, associated with G proteins.