Unit 4 Flashcards
Receptors
Proteins that detect external signals (like an antenna)
Ligands
Molecules that bind to receptors (signals)
Steps of cell signaling
Reception
Transduction
Response
Receptors
Ion channels, coupled receptors (second messengers)
Ligands
Gases, ions, lipids, proteins, amino acids, nucleotides
Polar
Structure determins function
Ligand binding to a receptor changes the receptors shape “conformational change”
G protein-coupled receptors
Receptor activates G protein which activates enzymes
Ligand —> GPCR —> G protein —> Enzyme —> second messengers
Intracellular (inside cell)
Nonpolar ligands
Regulate gene expression
Transduction
Amplification : ligand binging to one receptor results in many molecules inside the cell
Second messengers
Activate enzyme withing the cell through GPCR
Phosphorylation
CHanges the shape of proteins
Gene expression
Activation of transcription of specific genes
Enzyme activation
Turning on kinases
Apoptosis
Programmed cell death
Different cells have ____
Different responses to the same ligand
