Vacuole

• Plant cell's vacuole - maintain turgor pressure to keep the cell from wilting
• Animal cell's vacuole - storage of nutrients, ions, and water
• Chloroplast and mitochondria are similar in a way that they are sites for ATP synthesis
• Endomembrane system - synthesis and modification of proteins and lipids
• Biological system - group of organs that work together to perform certain tasks
• Metabolic reactions - will not proceed without enzymes which act as catalysts of biological reactions
• Two kinds of Transport Mechanisms - active and passive transport
• Active transport - requires and energy to move molecules from lower to higher concentration
• Passive transport - does not use energy
• Osmosis - movement of water molecules through a plasma membrane from a region of low concentration to a region of high concentration
• Diffusion - passive movement of particles from a region in which they are in higher concentration to regions of lower concentration
• Facilitated diffusion is a process by which substances are transported across cell membranes by means of protein carrier molecules
• Concentration - number of particles per unit volume