AUA Med 1-- Biochemistry-- Cell Signaling – Questions With Complete Solutions

What is cell signalling? correct answer: "Transduction of message(s) from one cell to another cell resulting in altered behaviour of target cell" What are the basic requirements of cell signalling? correct answer: 1. Signalling cell. 2. Extracellular ligand (signalling molecule). 3. Target (responding) cell. 4. Receptor (on plasma membrane or intracellular) Illustrate a general schematic of cell signaling correct answer: What are the 3 types of signalling? correct answer: 1. Endocrine. 2. Paracrine. 3. Autocrine What is endocrine signalling? correct answer: Signalling molecules travel through bloodstream and interact with distant target cells What is paracrine signalling? correct answer: Signalling molecules act on nearby cells What are the subtypes of paracrine signalling? correct answer: Juxtacrine (contact-dependent), Synaptic What is juxtracrine (contact-dependent) signalling? correct answer: Signalling molecules stay attached to synthesising cell while interacting with target cell What is synaptic signalling? correct answer: Action potentials used to transmit signals mediated by neurotransmitters What is autocrine signalling? correct answer: Synthesizing cell is also target cell What happens if a cell does not receive a "survival" signal? correct answer: Apoptosis (cell death) Can an individual signalling molecule have different effects on different target cells? correct answer: Yes