adaptions/rate of photsynthesis

• MRS GREN

  movement, respiration, sensitivity/growth, reproduce, excrete, nutrition(respiration releases energy, all others take in energy)
• equation for photosynthesis

  carbon dioxide + water ➡️ glucose + oxygen

  CO2 + H2O ➡️ C6H12O6 + O2

  balanced= 6CO2 + 6H2O ➡️ C6H12O6 + 6O2
• chlorophyll


  green chemical that absorbs sunlight
• leaf adaptations 


  large surface area-to absorb lots of light

  thin- carbon dioxide has a short diffusion distance

  vascular bundles(veins)- support leaf and transport water to and glucose away from leaf
• uses of glucose

  -respiration(release energy)

  -stored in insoluble starch in roots(when plant isn’t doing respiration so it doesn’t die)

  -combined with nitrate ions to produce amino acids to make protein

  -produces cellulose(makes cell walls)

  -produces insoluble fat and oils for storage
• palisade cells in leaf


  where most photosynthesis happens
• spongy cells in leaf

  mesophyll, spaces between them to easily allow co2 to get to where photosynthesis happens
• guard cells in leaf

  can swell and shrink by gaining and losing water to open and close stomata(open=day/closed=night)
• limiting factors

  -water(less likely)

  -light intensity

  -carbon dioxide
• ways to measure rate of photosynthesis

  -loss of co2(ml/min)

  -loss of water(g/min)

  -production of glucose(g/min)

  -production of oxygen(ml/min)
• -photosynthesis uses energy to change co2 and water into glucose and oxygen

  -takes place in the chloroplasts

  -photosynthesis is endothermic(energy transferred from environment)
• rate of photosynthesis will increase as light intensity increases but only to a certain point, this means something else is limiting(e.g. temperature) this is the same for CO2

  
• if temp is the limiting factor it’s because it is too low and the enzymes needed for photosynthesis work slower at low temps but if the plant gets too hot it will damage the enzymes( this usually happens at 45 degrees)

  
• water moves into the plant(root hair cell) by osmosis and from the roots to the leaves by transpiration up the xylem(water pulled up due to cohesion between water molecules)and evaporates through the stomata
• xylem

  -have thick walls made of lignin

  -transport water and minerals up the one way flow of sap—cells have no end walls between them

  
• phloem

  -has thin cell walls made of cellulose

  -water and glucose are transported both ways as has two way flow sap

  -cella have end walls meaning there are perforations(holes to let water and glucose through)