To discuss:
Osmosis, examples of its physiological and clinical relevance, factors that determine its speed and direction, and the role of aquaporins.
Introduction:
Cells are regarded as the simplest unit (structural and functional) of life. Cellular membrane, nucleus, and cytoplasm are the three major components of a cell. Cellular membrane, which surrounds the entire cell, is composed of phospholipids and proteins. By defining the cell’s boundary, plasma membrane controls the intake of substances into the cell and releases substances out of the cell. This selectively permeable membrane is a phospholipid bilayer with proteins inserted in it. It acts as both wall and gateway between the extracellular fluid and the cytoplasm. Both passive mechanisms (diffusion, filtration, and osmosis) and active transports are involved in the transport of a few molecules across the cell membrane. It permits the passage of some substances (wastes and nutrients), while hindering the passage of other substances (phosphates and proteins).
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Anatomy & Physiology: The Unity of Form and Function
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- The movement of water through a semipermeable membrane from a region of lower solute concentration to a region of higher solute concnetration is called _________ osmosis diffusion solubility gradientarrow_forwardWhich portion of the phosphotidylinositol molecules contributes to the fluidity of a membranearrow_forwardDeine the various forms of bulk transport that can move materials into or out of a cell.arrow_forward
- The portion of osmotic pressure exerted by osmotic pressure ( or oncotic pressure ) small ions proteins large ions lipidsarrow_forwardTrue or false the cell membrane equalizes osmosis pressure to protect cell.arrow_forwardThe tendency of molecules (particles) to extend or spread out from a region of higher concentration to a region of lower concentration. active transport diffusion facilitated diffusion osmosisarrow_forward
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