Biological molecules

Chemical Elements in Biological Molecules

Carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus.

Hydrogen Bonding

Weak electrostatic attraction between a hydrogen atom and an electronegative atom

Monomers and Polymers

Monomers are small molecules that can join together to form larger molecules called polymers.

Condensation reactions link monomers to form polymers, while hydrolysis reactions break polymers into monomers.

Synthesis and Breakdown of Disaccharides and Polysaccharides

Disaccharides and polysaccharides are synthesized by glycosidic bond formation and broken down by glycosidic bond hydrolysis.

Structure of Starch, Glycogen, and Cellulose

Starch and glycogen are composed of glucose units and are used for energy storage

cellulose is a structural polysaccharide made of glucose and provides rigidity to plant cell walls.

General Structure of an Amino Acid

Central carbon atom bonded to a hydrogen atom, an amino group, a carboxyl group, and a variable R group.

Synthesis and Breakdown of Dipeptides and Polypeptides

Dipeptides and polypeptides are formed by peptide bond formation between the amino group of one amino acid and the carboxyl group of another.

Levels of Protein Structure

Primary, secondary, tertiary, and quaternary.

Structure and Function of Globular Proteins

Compact, spherical proteins with hydrophilic exteriors and hydrophobic interiors, often involved in enzymatic reactions or transport.

Properties and Functions of Fibrous Proteins

Fibrous proteins are elongated and structural, providing strength and support to tissues and cells.

Inorganic Ions in Biological Processes

Sodium (Na+)

potassium (K+)

calcium (Ca2+)

magnesium (Mg2+)

chloride (Cl−)

phosphate (PO43−)

Structure of Triglycerides and Phospholipids

Triglycerides consist of glycerol bonded to three fatty acids

Phospholipids have a phosphate group in place of one fatty acid. When placed in water they form a double layered structure called a bilayer

Synthesis and Breakdown of Triglycerides

Triglycerides are synthesized by esterification of glycerol and fatty acids and broken down by hydrolysis of ester bonds.

Relationship between Molecule Properties and Functions

The structure of molecules determines their functions in living organisms.

The hydrophobic tails and hydrophilic heads of phospholipids enable them to form the lipid bilayer of cell membranes, providing a barrier that regulates the passage of molecules.

Monosaccharides

Major energy source and component of nucleic acids and lipids

Single monomer

what is glycerol

glycerol is a 3-carbon alcohol with a hydroxyl group attached to each carbon

Condensation

When 2 molecules combine to form a single molecule (water is lost during the reaction)

Hydrolysis

When water is used to break down the bonds of a particular substance

Polysaccharide

Structural and storage role in organisms

contains >20 monomers

Oligosaccharides

Serves structural and regulatory roles and are associated with proteins and lipids

contains 2-20 monomers