Preliminary

• The growth and function of a cell is strongly dependent upon
• Resting potential of a cell


  The balance between the activity of active and passive carrier mechanisms
• Osmosis


  Movement of water from area of higher concentration to lower concentration
• Receptor


  A structure that monitors changes in a controlled condition and sends input to a control center
• Protein of the plasma membranes do not function as structural units
• Lymphatic system


  Responsible for the protection of the body against invading bacteria
• Movement across the cell membrane

  • Diffusion
  • Osmosis
  • Active transport
  • Pinocytosis
  • Phagocytosis
  • Exocytosis
• Rough ER


  Contains a granular, ribosomal portion which is the site of protein synthesis
• Osmosis


  Net movement of water across the cell membrane, occurring because of a difference in water concentrations on the two sides of the membrane
• Membrane permeability

  Net flux proceeding down the concentration gradient
• Organ system


  The brain and spinal cord work together to do a specific job
• Mediated transport system


  Characterized by specificity, competition, and saturation except DIFFUSION COEFFICIENT OF THE MOLECULE.
• Excitability


  Capability of a cell to convert the resting potential to one that changes rapidly in response to a certain stimulus
• Functions of the plasma membrane


  • Separation of the cytoplasm from the extracellular fluid
  • Regulation of exchange of materials with the extracellular environment
  • Sensitivity to chemical changes in the extracellular fluid
  • Structural support
• Plasma membrane


  Composed of a bilayer of phospholipids
• Excitability


  Property of neurons and muscle cells
• Extracellular ions


  • Sodium
  • Chloride
  • Bicarbonate
• Intracellular fluid contains carbon dioxide and other cellular waste products
• Phospholipid molecule


  Tails are hydrophobic
• Digestive system does not function for excretion
• Anus is not an organ of the urinary system
• Integral proteins do not function to support the plasma membrane
• Glycocalyx does not have a positive electrical charge
• Concentration gradient


  Difference in the concentration of a chemical from one place to another
• Sources of cellular energy for active process in the transport process of the plasma membrane

  • Energy obtained from hydrolysis of ATP
  • Energy stored in the ionic concentration
  • From carrier proteins
• Diffusion


  Passive process in which the random mixing of particles in a solution occurs because of the particle's kinetic energy
• The higher the temperature the faster the rate of diffusion
• Cytoskeleton is not a site for chemical reactions
• Golgi apparatus


  Membranous sacs that collect, package and distribute proteins and lipids produced by the ER
• Peroxisomes do not function to breakdown bone to release calcium ions
• Extracellular ions


  • Sodium
  • Proteins
  • Chloride ions
• Concentration gradients of ions

  Result from permeability characteristics of the plasma membrane
• Functions of the Golgi apparatus

  • It is a sac-like organelle
  • It is located near the nucleus
  • It helps in transporting the particles throughout the cell
• The phosphate end of the phospholipid is hydrophilic, and the fatty acid portion is hydrophobic
• Functions of the integral proteins

  • Controllers of transport of substances through the cell membrane "pores"
  • Act as carrier proteins for transporting substances that otherwise could not penetrate the lipid bilayer
  • Act as enzymes that catalyze specific chemical reactions at the inside or outside surface of the cell
  • Serve as receptors for water-soluble chemicals, such as peptide hormones, that do not easily penetrate the cell membrane
• Sodium and potassium pumps


  Examples of active transport
• The greater the difference in concentration between the two sides of the membrane, the higher is the rate of diffusion
• Co-transporters


  Carry two substances across the membrane in the same direction
• Uncharged non polar molecules such as water, urea, and small alcohols also pass through the lipid bilayer by simple diffusion
• Enzymes


  Catalyze specific chemical reactions at the inside or outside surface of the cell