life functions

• Metabolism


  The sum of all chemical reactions that take place inside a cell
• ATP


  Primary energy source of the cell
• ADP


  Precursor to ATP, can convert back to ATP whenever energy is needed
• Anna the anabolic process


  Converts ATP to ADP by tearing off a small part of the ATP bill
• Cats the catabolic process


  Give money (energy/ATP) as an apology when they destroy or break something apart
• No process is better than the other
• Eating vegetables can help your emotional state because of energy
• Endergonic


  Reaction that consumes energy and is involved in anabolism
• Exergonic


  Reaction that releases energy and is involved in catabolism
• Energy is what it takes to do work, mostly moving matter in the form of vibration/heat, rotation, and kinetic energy
• Potential energy is the stored ability to do work
• Catalyst


  A substance that speeds up a chemical reaction without being changed
• Enzyme


  A biological catalyst (usually a protein)
• Substrate


  The reactant molecule that an enzyme works on
• Active site


  The part of the enzyme where the substrate binds
• Enzymes

  • They are usually proteins, though some RNA molecules act as enzymes too
  • They lower the activation energy of a reaction - that is the required amount of energy needed for a reaction to occur
  • They bind to a substrate and hold it in a way that allows the reaction to happen more efficiently
• Enzyme structure and function

  1. Enzyme binds to substrate

  2. Enzyme changes shape slightly, fitting tightly with substrate and forming the enzyme/substrate complex
• Factors affecting enzyme activity

  • Temperature
  • pH
  • Enzyme concentration
  • Substrate concentration
• Raising temperature generally speeds up a reaction, and lowering temperature slows down a reaction. However, extreme high temperatures can cause an enzyme to lose its shape (denature) and stop working.
• Each enzyme has an optimum pH range. Changing the pH outside of this range will slow enzyme activity. Extreme pH values can cause enzymes to denature.
• Increasing enzyme concentration will speed up the reaction, as long as there is substrate available to bind to. Once all of the substrate is bound, the reaction will no longer speed up, since there will be nothing for additional enzymes to bind to.
• Increasing substrate concentration also increases the rate of reaction to a certain point. Once all of the enzymes have bound, any substrate increase will have no effect on the rate of reaction, as the available enzymes will be saturated and working at their maximum rate.
• Enzymes


  • They are "specific" - each type of enzyme typically only reacts with one, or a couple, of substrates
  • They are reusable - they are not reactants and are not used up during the reaction
• pH


  A numeric scale used to specify the acidity or basicity (alkalinity) of an aqueous solution
• pH


  The negative of the logarithm to base 10 of the concentration, measured in units of moles per liter, of hydrogen ions
• pH


  The negative of the logarithm to base 10 of the activity of the hydrogen ion
• Types of enzymes by how they break reactant

  • Oxidoreductases
  • Transferases
  • Hydrolases
  • Lyases
  • Isomerase
  • Ligases
  • Translocase
• There are about 2000 kinds of enzymes by what reactant they break
• One third of enzymes will be about plants and the rest will be about the human body
• Reactant


  A substance that changes in a chemical reaction
• When enzymes are denatured

  The shape of the protein is changed permanently, thus the active site is changed permanently as well
• When enzymes are inactive


  The enzyme is fine, just needs an increase in temperature to work again
• Enzymes can be denatured by extreme cold AND hot temperatures
• Passive transport


  Type of transport that does not require energy to occur
• Concentration gradient


  A region of space over which the concentration of a substance changes
• Permeability


  The quality of a membrane that allows substances to pass through it
• Equilibrium


  The state at which a substance is equally distributed throughout a space
• Diffusion


  Substances move from an area of high concentration to an area of low concentration, until the concentration becomes equal throughout a space
• Diffusion


  • This is also true for some substances moving into and out of cells
  • Because the cell membrane is semipermeable, only small, uncharged substances like carbon dioxide and oxygen can easily diffuse across it
  • Charged ions or large molecules require different kinds of transport
• Facilitated diffusion


  Although gases can diffuse easily between the phospholipids of the cell membrane, many polar or charged substances (like chloride) need help from membrane proteins<|>Membrane proteins can be either channel proteins or carrier proteins<|>Substances transported through facilitated diffusion still move with the concentration gradient, but the transport proteins protect them from the hydrophobic region as they pass through