1. Exchange
   1. photsynthesis
      1. CO2
      2. water
   2. respiration
      1. glucose
      2. oxygen
   3. waste substances
   4. pass though EXCHANGE SURFACES
      1. adapted to maximise effectriveness
   5. Active Transport
      1. Low to High concentration
   6. Diffusion
      1. high to low concentration
         1. spread of a weird smell
         2. dissolved particles
            1. in/out cell membranes
   7. Osmosis
      1. only water moevement
      2. across a partially permeable membrane
         1. cell membrane
      3. high watrer concentration to low water concentration
2. Leaf Structure
   1. CO2
      1. diffuse from air into airspace
         1. stomata
      2. diffuse from airspace into cell
      3. photosynthesis in cell
   2. water vapour and oxygen
      1. out
         1. stomata
      2. watervapour
         1. diffusion
         2. transpiration
            1. greatest
            2. hot
            3. dry
            4. windy
   3. stomata
      1. size
         1. guard cell control
            1. close if net loss of water
      2. singular - stoma
   4. shape
      1. flattened
         1. increased are for exchange
      2. airspace
         1. increase surface area around cells for absorption
   5. cactus
      1. stem
         1. photosynthesis
      2. stomata
         1. open at night
            1. cooler
      3. stores CO2 at night
         1. uses CO2 during day
3. Respiration System
   1. blood
      1. oxygen in
      2. carbon dioxide out
      3. lungs
         1. found in thorax
            1. top part of body
         2. diaphragm
            1. separates lungs form lower part
         3. protected by rib cage
         4. air in
            1. trachea
            2. 2 bronchi tubes
            3. smaller bronchiole tubes
            4. split into alveoli
            5. enormous surface are (75m2)
            6. moist lining for dissolving gases
            7. very thin walls
            8. copious blood supply
            9. DIFFUSION of gases
         5. gas transfer to blood happens in lungs
         6. breath in
            1. intercostal muscles & diaphragm contract
            2. diaphragm flattens out
            3. thorax volume increases
            4. decrease pressure = air in
         7. breath out
            1. intercostal muscles and diaphragm relax
            2. diaphragm moves up
            3. thorax volume decreases
            4. air forced out
4. Digestive System
   1. Solution exchange
   2. small intestines
      1. villi
         1. big surface area
         2. single layer surface cells
         3. digested food absorbed
            1. into blood
            2. DIFFUSION
            3. ACTIVE TRANSPORT
   3. active transport
      1. glucose from gut
      2. glucose from kidney tubules
      3. high concentration glucose & amino acids in gut
         1. natural diffusion
      4. low concentration glucose and amino acids in gut
         1. active transport
         2. allows uptake of nutrients]
5. Root Hairs
   1. active transport
      1. against the concentration gradient
      2. needs energy
         1. respiration
   2. large surface are
      1. absorbe
         1. water
         2. mineral ions
            1. active transport