bio chem

Ion

An atom or molecule that has gained or lost electrons, resulting in a net electrical charge.

Cation

A positively charged ion.

Anion

A negatively charged ion.

Electronegativity

The tendency for an atom of a given chemical element to attract shared electrons when forming a chemical bond.

Isomers

Molecules that have the same molecular formula but different structural arrangements of atoms.

Anabolic reactions

A metabolic process that builds larger molecules from smaller ones, typically during energy input.

Catabolic reactions

A metabolic process that breaks down complex molecules into simpler ones, releasing energy in the process.

Endergonic reactions

Reactions that require energy to be driven, absorbing energy in the form of work (non-spontaneous).

Exergonic reactions

A chemical reaction that releases energy, making it spontaneous.

Gibbs Free Energy

A thermodynamic quantity that represents the usable energy in a system.

Hydrogen bonding

Electrostatic attraction between a hydrogen atom and another electronegative atom (e.g., nitrogen, oxygen, fluorine).

Cohesion

Attraction of molecules of the same kind, strong in water.

Adhesion

Attraction of molecules of different kinds, strong in water.

Polar molecule

A molecule with an uneven distribution of electrical charge, resulting in a separation of charge.

Non-polar molecule

A molecule with an even distribution of electrical charge, having no positive or negative poles.

Phosphate group

A functional group consisting of a phosphorus atom bonded to four oxygen atoms, important in energy transfer (e.g., ATP).

Carbonyl group

A functional group composed of a carbon atom double-bonded to an oxygen atom, found in ketones and aldehydes.

Carboxyl group

A functional group (-COOH) that acts as an acid, found in fatty acids and amino acids.

Hydroxyl group

A functional group (-OH) that is polar and helps in solubility.

Amino group

A functional group (-NH2) that acts as a base and forms peptide bonds.

Monomer

The simplest form of a biomolecule that can join to form polymers.

Polysaccharide

A polymer made of many monosaccharides, providing long-term energy storage and structural support.

Triglyceride

A type of lipid made from glycerol and three fatty acids, important for long-term energy storage.

DNA

A nucleic acid that stores genetic information; composed of nucleotides.

RNA

A nucleic acid that plays roles in protein synthesis and gene expression.

ATP

A modified nucleotide that stores energy.

Peptide bond

A covalent bond formed between the carboxyl group of one amino acid and the amino group of another.

Fluid Mosaic Model

A model describing the structure of cell membranes, depicting a flexible and dynamic arrangement of various molecules.

Selective permeability

The property of cell membranes to allow certain substances to pass while restricting others.

Diffusion

The movement of molecules from an area of higher concentration to an area of lower concentration.

Osmosis

The diffusion of water across a semi-permeable membrane.

Facilitated diffusion

The process of passive transport of molecules across a cell membrane via protein channels.

Active transport

The movement of substances against their concentration gradient, requiring energy.

Endocytosis

The process by which cells engulf materials from their environment.

Exocytosis

The process by which cells expel materials to the outside of the cell.

Enzyme

A biological catalyst that speeds up chemical reactions by lowering the activation energy.

Optimal pH

The pH at which an enzyme functions most effectively.

Amylase

An enzyme that breaks down starch into maltose.

Lipase

An enzyme that breaks down lipids into glycerol and fatty acids.

Pepsin

An enzyme that breaks proteins into peptides, active in the stomach.

DNA polymerase

An enzyme that synthesizes new DNA strands by adding nucleotides.

ATP synthase

An enzyme that catalyzes the formation of ATP from ADP and phosphate.