topic 2 - organisation

• what are enzymes ?

  biological catalysts that speed up chemical reactions in the body and enzymes are large proteins made out of long chains of amino acids
• what does every enzyme have ?

  an active site and substrate which are complementary in shape - active site has a unique shape that fits onto the substrate, forming new products
• what is amylase and what does it break down ?

  a digestive enzyme produced in the salivary glands and it breaks down starch into sugars
• what does protease enzymes break down ?

  proteins into amino acids
• where are protease enzymes produced by ?

  pancreas, small intestine and stomach
• what do carbohydrase enzymes break down into ?

  carbohydrates into sugars
• what do lipase enzymes do ?

  break down fats into fatty acids and glycerol
• where are lipase enzymes produced ?

  pancreas and small intestine
• what is the function of the small intestine ?

  • produces lipase, amylase and protease enzymes to complete digestion it is where digested food is absorbed out of the digestive system into the blood
• what is the function of the large intestine ?

  where excess water is absorbed from the food
• what is the function of the liver?

  where bile is produced and bile neutralises stomach acid and emulsifies fats
• what is the function of the stomach ?

  it pummels the food with its musuclar walls and produces protease enzymes it produces hydrochloric acid which kills bacteria and gives the right PH for the protease enzyme to work on
• what is the benedicts test and what happens ?

  it is used on glucose and has a colour change from clear blue to red
• what is biuret test and what happens ?

  it is used on proteins and it turns purple
• what happens during the iodine test ?

  it turns starch from blue to black
• what happens during ethanol test ?

  turns fats into white
• what is the circulatory system made up of ?

  arteries, heart and capillaries
• what is the function of the circulatory system ?

  • provides cells with nutrients and circulates oxygen and removes carbon dioxide
• what is the heart ?

  an organ which pumps blood around the body ]
• how many chambers does the heart have and what are they called ?

  4 chambers - 2 atria and 2 ventricles
• what does the aorta do ?

  carries oxygenated blood from the heart around the body
• what does the pulmonary artery do ?

  carries deoxygenated blood from the heart to the lungs
• what does the pulmonary vein do ?

  carries oxygenated blood from the lungs to the heart
• what does the left ventricle do ?

  pumps blood around the rest of the body
• what does the right ventricle do ?

  pumps blood to the lungs where gas exchange takes place
• what does oxygenated mean ?

  high in oxygen and low in oxygen
• what does deoxygenated mean ?

  low in oxygen, high in carbon dioxide
• what is blood and what does it do ?

  Blood is tissue that transports materials and distributes heat around the body
• what are the 4 components of blood ?

  red blood cells, white blood cells, plasma and platelets
• what substances does blood transport ?

  oxygen , nutrients and carbon dioxide
• what do the arteries do ?


  carry blood away from the heart
• what do the white blood cells do ?

  • protects the body from pathogens and help fight off disease white blood cells have a nucleus and they defend against microorganisms that cause disease
• what is plasma ?


  a light yellow liquid
• what do platelets do ?

  • help clot the blood together at a wound and they stop microorganisms from getting in the wound
• 2 ways whiteblood cells defend against microorganisms that cause disease

  • they can produce antibodies to fight microorganisms they can engulf unwelcome microorganisms and digest them
• what do lymphocytes do ?

  they produce antibodies that stick pathogens together
• what are platelets ?

  small fragments of cells and they have no nucleus
• what does plasma do ?


  carries a lot of substances such as carbon dioxide, nutrients , glucose , proteins and waste products
• what do red blood cells do and name the features?

  they carry oxygen around the body and they have no nucleus ,allowing for space for oxygen and they contain haemogolbin and are biconave shape
• what are capillaries ?

  tiny blood vessels