Enzyme Mechanisms of Catalysis
Enzymes accelerate chemical reactions by lowering the activation energy through several catalytic strategies including acid-base, covalent, and metal-ion catalysis.
BiologyEnzyme Regulation
Enzyme activity is regulated through multiple mechanisms including allosteric regulation, covalent modification, zymogen activation, and control of enzyme quantity.
BiologyCholesterol Metabolism
Cholesterol is an essential sterol that modulates membrane fluidity and serves as a precursor for bile acids, steroid hormones, and vitamin D.
BiologyEicosanoids
Eicosanoids are signaling molecules derived from arachidonic acid that mediate inflammation, fever, pain, blood clotting, and smooth muscle contraction.
BiologyLipid Structure and Classification
Lipids are a diverse group of hydrophobic or amphipathic molecules that serve as energy stores, structural components of membranes, and signaling molecules.
BiologyLipoproteins and Lipid Transport
Lipoproteins are complexes of lipids and proteins that transport hydrophobic lipids through the aqueous environment of the bloodstream.
BiologyMembrane Lipids
Membrane lipids form the structural foundation of biological membranes, providing a selective barrier that defines cellular and organellar boundaries.
BiologyPhospholipid and Sphingolipid Metabolism
Phospholipids and sphingolipids are the major structural lipids of membranes, and their synthesis, degradation, and remodeling are tightly regulated.
BiologyDNA Replication
DNA replication is the process by which a cell duplicates its genome before cell division, ensuring each daughter cell receives an identical copy of the genetic material.
BiologyDNA Structure and Topology
DNA is a double-stranded helix that stores genetic information, with its structure and topology being fundamental to its function in replication, transcription, and repair.
BiologyGene Regulation and Epigenetics
Gene regulation controls when, where, and how much a gene is expressed through the combined action of transcription factors, chromatin modifications, and non-coding RNAs.
BiologyRNA Structure and Types
RNA is a versatile nucleic acid that functions in information transfer, catalysis, gene regulation, and cellular structure, existing in many distinct forms.
Biology
