Diffusion in Biology

• More collisions against the cell membrane and across them occur with more random collisions
• The higher the temperature, the faster molecules move as they have more energy
• Diffusion helps living things to obtain their requirements, get rid of many waste products, and carry out gaseous exchange for respiration
• Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration
• Factors that influence Diffusion


  • Ratio of surface area to volume
  • Temperature & Concentration
  • Distance
• Substances that are able to move out of cells include digested food products like glucose, amino acids, fatty acids, glycerol, etc.
• The faster movement of molecules results in more random collisions
• Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration as a result of a concentration gradient
• The substances that are able to move out of cells are carbon dioxide, water vapor, and oxygen
• Diffusion, osmosis, and active movement are the main ways that molecules move into and out of cells through the cell membranes
• The energy for diffusion comes from the kinetic energy of the random movement of molecules and ions
• Molecules moving out of cells include carbon dioxide, water vapor, and oxygen
• Greater difference in concentration across the membrane

  Results in a faster rate of