Organisation (2)

• Cells are the basic building blocks of all living organisms
• Tissue


  A group of cells with similar structure and function
• Organ


  A group of tissues performing specific functions
• Organ system


  A group of organs performing a specific function
• Organism


  A group of organ systems together
• Enzymes


  Protein molecules found in cells that speed up reactions in the body
• Enzymes


  • They can be reused as their shape remains unchanged
  • They depend on their shape to work
• Lock and key model

  Explains how enzymes work - the substrate molecule fits into the active site of the enzyme
• Metabolism


  Reactions that build up and break down molecules, controlled by enzymes
• Optimum temperature


  The temperature at which an enzyme works at its fastest rate
• Denaturation


  When the shape of the enzyme's active site is permanently changed, causing it to stop working
• Optimum pH


  The pH at which an enzyme works at its fastest rate
• Digestive system organs


  • Mouth
  • Esophagus
  • Stomach
  • Pancreas
  • Small intestine
  • Large intestine
  • Rectum
  • Anus
  • Liver
  • Gallbladder
• Carbohydrase


  Enzyme that breaks down carbohydrates
• Lipase


  Enzyme that breaks down lipids
• Amylase


  Enzyme that breaks down starch
• Protease


  Enzyme that breaks down proteins
• The mouth produces amylase, the stomach produces protease, the pancreas and small intestine produce all four enzymes
• Carbohydrate


  Food group broken down by carbohydrase enzymes into simple sugars
• Starch


  Carbohydrate broken down by amylase into simple sugars
• Protein


  Made of amino acids, broken down by protease enzymes
• Lipid


  Also known as fat, broken down by lipase enzymes into glycerol and fatty acids
• Bile


  Produced by the liver, helps digest lipids by emulsifying them
• Iodine test


  Tests for the presence of starch, turns blue-black in the presence of starch
• Biuret test


  Tests for the presence of proteins, turns lilac in the presence of proteins
• Lipid test


  Tests for the presence of lipids, forms a cloudy white emulsion
• Benedict's test


  Tests for the presence of sugars, changes colour from blue to brick red
• Aorta


  Major blood vessel carrying oxygenated blood from the heart to the body
• Vena cava


  Major blood vessel carrying deoxygenated blood from the body to the heart
• Pulmonary artery


  Carries deoxygenated blood from the heart to the lungs
• Pulmonary vein


  Carries oxygenated blood from the lungs to the heart
• Double circulatory system


  Blood is pumped to the body by the left side of the heart and to the lungs by the right side
• Bronchi


  Smaller tubes branching off from the trachea
• Alveoli


  Small air sacs in the lungs where gas exchange occurs
• Left atrium


  Chamber of the heart that receives oxygenated blood from the lungs
• Left ventricle


  Chamber of the heart that pumps oxygenated blood to the body
• Right atrium


  Chamber of the heart that receives deoxygenated blood from the body
• Right ventricle


  Chamber of the heart that pumps deoxygenated blood to the lungs
• Pacemaker


  Structure in the heart that controls the resting heart rate
• Artery


  Blood vessel with a narrow lumen, thick muscle and elastic tissue walls to withstand high pressure