PHYL 2041 Lecture Notes - Lecture 1: Gas Constant, Nernst Equation, Electrochemical Gradient

• School: Dalhousie University
• Department: Physiology
• Course: PHYL 2041
• Professor: Dr. Krueger

Document Summary

Biological membranes = lipids that comes in different forms and shapes. (cholesterol, phospholipids, glycolipids); lipids have a hydrophobic tail and a hydrophilic head. Membranes also contain proteins in them (peripheral, integral) Membranes are very fluid structures with their proteins moving. Plasma membranes = membrane that separates the intracellular contents from the extracellular environment. They allow the cell to achieve a certain structure and to communicate/connect with other cells. Cell communication occurs via neurotransmitter receptors and hormone receptors. They also maintain cellular homeostasis and acts as a barrier to the movement of molecules and selectively transports other molecules. Hormones are in different concentrations inside/outside the cell. Some substances make it across membranes through diffusion (gases); many are also lipophilic that are readily permeable and can diffuse through membranes. Most substances cannot readily pass through biological membranes need to be transported. A lot of transport that occurs in cells has some travelling from one organelle to another. (exocytosis) likewise, endocytosis also occurs.