Topic 2: organisation

• A tissue is a group of specialised cells with a similar structure and function. The can be made from more than one type of cell.
• Organs are formed from a number of different tissues working together to produce a specific function
• Glands produce digestive juices containing enzymes
• The stomach produces hydrochloric acid to kill bacteria
• In the small intestine, soluble molecules are absorbed into the bloodstream
• The large intestine absorbs water for undigested food to produce poo
• Enzymes are biological catalysts which are present in many reactions.

  • They break down large molecules and join smaller ones
  • Shape is vital to its function
  • unique shaped active site where the substrate binds
• Lock and Key theory

  • Shape of substrate is complementary to the shape of the active site when bonds form
  • The reaction takes place and the products are released
  • optimum PH and temperature is 37 degrees
  • Enzyme denatures it is not complementary to the active site
• Amylase

  • breaks down starch
  • produced in the salivary glands, pancreas, and small intestine
• Protease

  • converts proteins into amino acids
  • found in the pancreas and small intestine
• Lipase

  • Converts lipids into fatty acids and glycerol
  • produced in pancreas and small intestine
• benedicts test is for sugars or glucose needs heat turns brick red if present
• Iodine test for starch turns blue/black if present
• biuret test is for protein turns purple if present
• Bile

  • produced in liver
  • stored in gallbladder
  • released in small intestines
  • neutralises hydrochloric acid
  • emulsify fat
  • large surface area chemically breaks down the lipids into gylcerol faster
• The liver processes and detoxifies the blood

  produces bile
• • Oxygen rich blood is found on the left hand side
  • travels to body cells
  • high oxygen content
  • low carbon dioxide content
• Veins carry blood to the heart at a low pressure
• Capilleries carry blood close to every cell to exchange substances
• The arteries carry blood away from the heart
• The four chambers of the heart are

  • right atrium
  • left atrium
  • right ventricle
  • left ventricle
• • Oxygen poor blood is on the right side
  • travels away from heart
  • low oxygen
  • high carbon dioxide content
• Coronary heart disease is the block of blood forming blood clots in the arteries making them narrow

  • caused by smoking or blood clots
• The aorta takes blood to the valves
• Meristemic tissues allows plants to grow which differentiates into cells
• Xylem

  • movement of water via transpiration
• Phloem

  • movement of food substances via translocation
• Spongy mesophyll contains air pockets that use diffusion as a gas exchange
• Palliside mesophyll contains lots of chloroplast and has rapid photosynthesis
• malignant

  • cancerous
  • tumour may split
  • travel to organs
  • divides rapidly
• Epidermal tissue is the waxy cuticle which reduces water loss by evaporation
• bengin

  • Not cancer
  • Grows until there is no room
  • dangerous
• ionising radiation which leads to cancer is uncontrollable growth and division which forms a tumor
• Factors effecting our body

  • smoking
  • alcohol
  • diet
  • stress
  • pregnancy
• Bad diet can lead to

  • not enough nutrients
  • type 2 diabetes
  • obesity
• Valve solutions are

  • mechanical hearts
  • heart transplants
  • can lead to blood loss
• Statin

  • drug to reduce cholesterol
  • reduces strokes
  • taken continously
  • side effects
• Stent

  • metal mesh in arteries
  • lower risk of heart attack
  • quick recovery
  • risk infection
  • risk thrombosis
• Platelets help clot blood
• White blood cells produce antibodies, engulf pathogens and produce antitoxins