Science EOU revision

• The 7 life processes

  • Sensitivity
  • Growth
  • Respiration
  • Nutrition
  • Reproduction
  • Excretion
  • Movement
• Muscles contract and parts of the body move
• Reproduction


  All living things need to make 'copies' of themselves
• Sensitivity


  The ability to respond to change in the surroundings
• Growth


  Organisms which are born small need to grow into adult size
• Respiration


  Oxygen is combined with food to release energy in cells
• Excretion


  Waste products from reactions in cells must be removed
• Nutrition


  Food is needed for new body structure and energy
• The initial letters of the 7 life processes spell MRS.GREN!
• Plants do all these 7 life processes, but less obviously
• Tissue


  A group of cells with similar structure and function
• Organ


  Two or more tissues working together
• All animals and plants are made up of cells
• Differences between animal and plant cells

  • Plant cell has a cellulose cell wall
  • Plant cell has a large central vacuole
  • Plant cell has chloroplasts
  • Animal cell has no cellulose cell wall
  • Animal cell has small vacuoles if any
  • Animal cell has no chloroplasts
• Many cells are highly specialised to do a certain job
• The seven constituents of food

  • Proteins
  • Carbohydrates
  • Fats
  • Vitamins
  • Minerals
  • Fibre
  • Water
• Proteins


  Huge, long chains of different amino acids
• Carbohydrates


  Huge, long chains of identical sugar molecules (starch) or individual sugar molecules (glucose)
• Fats


  Individual fat molecules
• Vitamins


  Needed only in tiny amounts for cell chemistry to keep everything working
• Minerals


  Iron and calcium are the ones you need to know for healthy blood and bones/teeth
• Fibre


  The indigestible part of food that prevents constipation and bowel cancer
• Water


  Our cells are mainly made up of water, to replace what is lost
• Digestion


  The breaking down of large insoluble molecules into smaller soluble molecules so they can be absorbed
• The 4 types of teeth

  • Incisors
  • Canines
  • Premolars
  • Molars
• Dental care


  Sugary food sticks to teeth, allowing bacteria to grow and cause plaque, which makes acid that eats away the tooth
• Parts of the digestive system

  • Mouth
  • Stomach
  • Small intestine
  • Large intestine
  • Liver
  • Pancreas
• Health problems caused by tobacco

  • Lung cancer
  • Lung infections
  • Emphysema
  • Bronchitis
  • Arterial disease
• Tobacco health problems


  Caused by substances in the tar of cigarette smoke, and cilia not working due to tar
• Health problems caused by alcohol abuse

  • Liver damage
  • Brain damage
  • Impaired judgement
  • Addiction
• Alcohol health problems


  Alcohol is a mild poison that causes parts of the liver to become fibrous and useless, and leads to increased brain cell death and reduced mental performance
• Health problems caused by solvent abuse

  • Hallucinations
  • Personality change
  • Organ damage
• Types of other drugs

  • Hallucinogens
  • Stimulants
  • Depressants
  • Painkillers
• Invertebrate groups


  • Arthropods
  • Molluscs
  • Annelids
• Vertebrate groups


  • Fish
  • Amphibians
  • Reptiles
  • Birds
  • Mammals
• Plant groups


  • Algae
  • Mosses
  • Ferns
  • Conifers
  • Flowering plants
• Steps in using a dichotomous key (method 1)

  • Has it got legs?
  • Has it got segments?
  • Has it got more than 3 segments?
  • Has it got a shell?
  • Has it got 6 legs?
• Steps in using a dichotomous key (method 2)

  • Has legs
  • Has no legs
  • Has a shell
  • Has no shell
  • Has 3 pairs of legs
  • Has more than 3 pairs of legs
  • Has a tail
  • Has no tail
• The same principle is used to identify plants using keys
• A habitat is the particular type of area in which an organism lives