osmosis, diffusion, active transport

• Rough Endoplasmic Reticulum

  • site of protein synthesis
  • made of flattened membranes with ribosomes on their surface
  • common in cells that make protein
• Mitochodrion ( Mitochondria)

  -made up of membrane which provide a large surface area for some of the reactions of aerobic respiration

  -this process releases energy which is needed to perform work in the cell

  -cells that require lots of energy
• cell membrane:

  surrounds the cytoplasm and controls the entry and exit of dissolved substances. Seperates the cell’s contents from its surroundings
• 5 things cells exchange with environment

  Glucose

  oxygen

  water

  carbon dioxide

  ions
• Diffusion


  The net movement of molecules within a gas or liquid from a region of high concentration to a region of lower concentration down a concentration gradient as a result of their random movement until an equilibrium is reached
• cell surface membrane is impermeable to …

  Proteins cause they are too big
• ways to increase diffusion

  short distances

  maintaining concentration gradients

  diffusion surfaces areas are large

  higher temperature
• osmosis


  the net movement of water particles from an area of high water potential to an area of low water potential down a water potential gradient, through a partially permeable membrane
• active transport


  the movement of particles or ions from an area of low concentration to an area of higher concentration against the concentration gradient through a partially permeable membrane using carrier proteins and energy
• where does energy for active transport come from?


  respiration in mitochondria. the more respiration a cell carries out the more active transport it can do
• what happens to particles who are too big for active transport and diffusion?


  specialized white blood cells that carry out phagocytosis