MUST REVISE

• Specialised cells 


  cells designed to carry out a particular role in the body. special structures and features, which make them adapted to a particular function. 
• embryonic stem cells are derived from embryos created through IVF (in vitro fertilisation) and donated with informed consent.
• Enzyme


  Biological catalyst - special type of protein that speeds up chemical reactions
• Denaturated


  This is caused by extreme temperatures and pH's - bonds are disrupted in the enzyme and it loses its shape and can no longer speed up reactions
• Specific


  Enzymes only catalyze ONE reaction - the active site fits with only one substrate.
• Factors that affect Enzyme Activity


  pH, temperature, and concentration of enzyme or substrate
• Ways to measure the rate of a reaction


  Quantity of product being made or the amount of substrates used up over time
• Catalyst


  Speeds up the rate of a chemical reaction
• Substrate


  The substance enzymes act upon
• Active Site


  Specific part of an enzyme where a substrate fits

  
• Lock and Key Model


  Enzymes and substrates fit together based on their specific shapes like a key fits a lock

  
• Enzyme Substrate Complex


  When the enzyme and substrate are locked together during a chemical reaction

  
• pH, Temperature, and Concentration


  Three factors that affect enzyme activity
• Acid


  ph between 0-7

  
• Base (alkaline)


  pH between 7-14

  
• Neutral


  pH of 7

  
• Optimal temperature


  Temperature at which enzyme works the best

  
• Protein


  Type of organic molecule an enzyme is
• Optimal pH


  pH at which an enzyme works best

  
• Which enzyme breaks down starch?

  Amylase
• Which enzyme breaks down protein?


  Protease
• Which enzyme breaks down lipids?


  Lipase
• Which enzyme breaks down maltose?


  Maltase
• What is the end product when starch is broken down?


  Maltose
• What is the end product when protein is broken down?


  Amino Acids
• What is the end product when lipids are broken down?


  Fatty acids and glycerol
• Communicable disease


  A disease caused by a pathogen which can be passed between animals or plants e.g. flu
• What is the end product when maltose is broken down?


  Glucose
• Where is amylase produced?


  Salivary glands and Pancreas
• Where is protease produced?


  Stomach and Pancreas
• Where is lipase produced?


  Pancreas
• Pathogen


  A disease-causing microorganism e.g. bacteria
• Where is maltase produced


  Small intestine
• How bacteria cause disease


  1. Divide rapidly by binary fission

  2. Kill cells

  3. Produce harmful toxins
• How viruses cause disease


  1. Invade and reproduce inside living body cells

  2. Lead to cell damage
• Monoclonal antibodies (mAbs)


  Antibodies that are clones from one parent cell, specific to one type of antigen
• Ways pathogens can be spread


  • By air - flu, tuberculosis, common cold
  • By water - fungal spores
  • By direct contact - plant diseases, sexually transmitted infections
• How do aphids cause damage to plants?


  They use their sharp mouthparts to extract sap from the plant phloem, weakening the plant. They are also vectors who can transfer pathogens from diseased plants to healthy plants.
• Ways to reduce the spread of pathogens


  • Hygiene - handwashing, disinfectants, tissues
  • Reducing contact with infected individuals - quarantine
  • Removing vectors - use of pesticides and insecticides, removal of habitats
  • Vaccination
• How can we reduce the number of aphids?


  1. Chemical pesticides

  2. Biological pest control - using ladybirds