BIO (Chapter 3)

• cholesterol


  a steroid-alcohol that regulates fluidity in plasma membrane. 
• integral proteins


  Proteins that are a permeant part of the plasma membrane 
• Transmembrane proteins


  Proteins that are integral proteins that spans the entire plasma membrane 
• Peripheral proteins


  Proteins that are temporarily attached to the plasma membrane. 
• cytoskeleton

  The microscopic web of protein filaments in the cytoplasm. It provides structure and support, and transports products into and out of the cell.
• Glycolipid


  a phospholipid bound to a carbohydrate 
• Glycoprotein


  a phospholipid bound to a protein 
• Saturated


  A fatty acid chain with only single bonds between carbon atoms.  
• unsaturated


  A fatty acid chain with double or triple bonds between carbon atoms. 
• Plasma membrane

  The phospholipid bilayer embedded with proteins separating the intracellular and extracellular environments. Also known as the cell membrane. 
• Intracellular

  inside the cell
• extracellular


  outside the cell
• Selective permeability


  A property of cell membranes that ensures only specific substances can pass across them. Also known as semipermeable. 
• Phospholipid


  The main molecule of which membranes are composed. They have a phosphate head and two fatty acid tails. 
• Phospholipid bilayer


  A double layer of amphiphilic molecules that forms the primary component of cell membranes.  
• Phosphate head


  The hydrophilic subunit of a phospholipid. It is made from glycerol and phosphate group, and it is also polar 
• Two fatty acid tails

  The hydrophobic subunit of a phospholipid. It is made from carbon and hydrogen, and it is also nonpolar 
• hydrophilic


  having a tendency to be attracted to and dissolve in water 
• polar


  describes a molecule with both a positive end and negative end. These tend to be hydrophilic 
• nonpolar


  describes a molecule with no clear positive end or negative end. These tend to be hydrophobic 
• hydrophobic


  Having the tendency to be insoluble and repel from water. 
• amphipathic


  describes molecules with both hydrophilic and hydrophobic components. Also known as amphiphilic. 
• Protein


  A class of biomacromolecule made of amino 3D shape, consisting of carbon, hydrogen and carbon, nitrogen and sometimes sulfur. 
• carbohydrate


  A class of biomacromolecule made from monosaccharide monomers consisting of carbon, hydrogen and oxygen. Also known as saccharides and sugars.
• Cholesterol


  A steroid-alcohol that regulates fluidity in the plasma membrane. 
• Plasma membrane


  the phospholipid bilayer and embedded proteins which separate the intracellular environment from the extracellular environment 
• Selective Permeability


  a property of cell membrane that ensures only specific substances pass across them. 
• Cytosol


  the aqueous fluid within the cell that surrounds the organelles inside a cell 
• Passive transport


  The movement of molecules through a sempermeable membrane and down the concentration gradient without an input of energy. 
• Active Transport


  Movement of molecules across a sempiermeable membrane that requires energy. 
• Diffusion


  The passive movement of molecules from an area of high concentration to an area of low concentration (down the concentration gradient) 
• Concentration Gradient


  the difference in solute concentration between two adjacent areas. 
• Kinetic Energy


  The energy a particle or body possesses due to motion. 
• Solute


  A substance that gets dissolved in the solvent 
• Solvent


  A liquid in which the solute is dissolved, forming a solution. 
• facillitated diggusion


  A type of passive transport where molecules move through a phospholipid bilayer with the aid of a membrane protein 
• Protein Channel


  A transmembrane protein pore in a phospholipid bilayer that selectively enables transport of large or polar molecules.  
• Carrier Protein


  A membrane protein that undergoes conformational change to transport molecules across a membrane. 
• Osmosis


  The passive transport of a solvent (typically water) through a semipermeable membrane from a region of low solute (high solvent) to high solute (low solvent) region.
• Tonicity


  A measure of the relative concentration of solutes on either side of sempipermeable membrane, described hypertonic, hypotonic, or isotonic.