Science

• Variable


  Any factor, trait, or condition that can exist in differing amounts or types
• Variable


  • A factor that can be changed in an experiment
• Types of variables in an experiment

  • Independent
  • Dependent
  • Controlled
• Independent variable


  The variable that is deliberately changed by the scientist
• Dependent variable


  The variable that is affected by changes made to the independent variable
• A well-designed experiment should have only one independent variable
• Photosynthesis


  The process where plants use light energy to make their own food
• Plants, and some other organisms, capture energy from sunlight and store it in a form that living things can use (chemical energy)
• Plants have a green pigment called "chlorophyll" which absorbs the light energy
• The chloroplast (tiny structure) is the specific location in the plant where photosynthesis takes place

  
• Autotroph


  An organism that makes its own food
• Heterotroph


  An organism that obtains its energy by consuming other organisms
• Types of consumers


  • Herbivores
  • Carnivores
  • Omnivores
• The Sun is the source of energy for nearly all life on Earth
• Energy flow in a food chain

  1. From the Sun to producers in the form of light

  2. Producers convert light energy into chemical energy

  3. Energy flows from one consumer to the next

  
• The first organism in a food chain is ALWAYS a producer
• Trophic level


  An organism's position in a food chain
• This food chain has 4 trophic levels
• Food web


  Made up of many food chains, shows how organisms are part of multiple food chains and feed on different things

  
• Atom


  Extremely tiny particle that makes up everything in the universe
• Atoms


  • Made of protons, neutrons and electrons
  • Protons are positively charged
  • Neutrons are neutral
  • Electrons are negatively charged
• Atomic number


  The number of protons an atom has

  
• The number of electrons an atom has is equal to the number of protons it has
• An atom is neutral because the positive and negative charges cancel out
• Electronic configuration


  The arrangement of electrons in shells
• Molecule


  A cluster of two or more non-metal atoms that are joined together and act as a unit
• Chemical bond


  The forces responsible for binding the atoms together in a molecule
• Physical change


  A change in the appearance of a substance, but the substance is chemically the same
• Chemical change


  A change that results in the formation of one or more new substances with different properties
• Atoms can combine with different atoms and make new substances, or substances can break apart into separate atoms
• Types of teeth


  • Incisors
  • Canines
  • Premolars
  • Molars

  
• Cavity


  A little hole in your tooth caused by tooth decay
• Dental plaque is the thin, colourless, sticky substance that builds up on your teeth each day and contains many layers of different bacteria
• When you eat or drink foods containing sugars, the bacteria in plaque produce acids that attack tooth enamel
• Digestion


  The process of breaking down relatively large, insoluble molecules in food into smaller, soluble molecules that can be absorbed into the bloodstream
• Enzymes help to break down food quickly
• Alimentary canal


  The long tube of organs that make up the digestive system
• Enamel


  The hard, outer layer of your teeth
• Plaque producing acids


  1. When you eat or drink foods containing sugars, the bacteria in plaque produce acids that attack tooth enamel

  2. The stickiness of the plaque keeps these acids in contact with your teeth and over time the enamel can break down
• Cavity


  A little hole in your tooth