HLSC 1F90 Lecture Notes - Lecture 14: Post-Translational Modification, Insulin Receptor, Chemical Classification
Document Summary
Chemical signals packaged in granules or secretory vesicles. Secreted by a cell or group of cells. Activate physiological response at low concentrations (nanomolar to picomolar) Hormones are secreted by endocrine glands or cells into the blood. Only target cells with receptors for the hormone respond to the signal. Clicker: what determines whether a cell in our body is a target for the hormone insulation: the presence of the insulin receptor in the cell. Hormone half-life: indicates length of activity. Typically, as a measure of the time needed to decrease its concentration in the circulation by 50% There are degrading enzymes in the circulation, live, and kidneys. Peptide/protein hormones: bind surface membrane receptors, cellular response through signal transduction system. Cholesterol derived: lipophilic and easily cross membranes, synthesized on demand in parent cell smooth er- diffuse out. Bind carrier proteins in blood: lengthens their half-life. Cytoplasmic or nuclear receptors: genomic effect to activate or repress genes for protein synthesis.