globals [ sugarcount sugarcount-old sugar-rate oxygencount O2-temp-count vapor-temp-count sugar-temp-count step time-unit day? sugarsmoothed sugarsmoothed-old sugar-rate-smoothed smoothness smoothness-2 percent-excited] turtles-own [ water-in-leaf? ] patches-own [ ] breed [light ] breed [sun] breed [sugar] sun-own [ old-xcor ] breed [ CO2 ] breed [ oxygen ] breed [ water ] breed [vapor] breed [ chloroplast ] chloroplast-own [ NADPH? ] to startup setup end to setup ca createplant createsun createchloroplast ask water [ set water-in-leaf? false] set day? true set sun-brightness 36 set co2-amount 14 set water-flow 10 end to go set step step + 1 shine-light if day-night? = true [day-night-cycle] takeup-water move-chloroplast color-sky set-CO2 photosynthesize make-oxygen make-sugar make-water-vapor ask sugar [ fd .1 if ycor < min-pycor + 1 [die] ] ask oxygen [ fd .2 set heading heading - 10 + random 20 if abs xcor > max-pxcor - 1 or abs ycor > max-pycor - 1 [die] ] ask vapor [ fd .2 set heading heading - 10 + random 20 if abs xcor > max-pxcor - 1 or abs ycor > max-pycor - 1 [die] ] plot-stuff tick end ;;SETUP PROCEDURES to createplant import-drawing "aspenleaftrans.png" ask patches [ set pcolor 103 if pycor <= -15 and pycor > -17 [set pcolor brown] if pycor <= -17 [set pcolor green ] ] end to createsun create-sun 1 [ set xcor -7 set ycor max-pycor - 3 set heading 90 set color yellow set size 4 set shape "circle" set day? true ] end to createchloroplast create-chloroplast 10 [setxy (5 - random 10) (5 - random 10) set color 64 set shape "circle" set size 4 set NADPH? false ] end ;;GO PROCEDURES to move-chloroplast ask chloroplast [fd .05 set heading heading + (10 - random 20) if distancexy 0 0 > 7 [ rt 180 ] ] end to shine-light if day? = true [ if random 100 < sun-brightness [ create-light 1 [set color yellow + 3 set size 2 setxy [xcor] of (one-of sun) [ycor] of (one-of sun) set heading 240 - random 120 set xcor xcor + random 5 - 2 fd 1 ] ] ] ask light [ fd .5 if abs xcor > max-pycor - 1 [die] if ycor < -14 [die] ] end to day-night-cycle ask sun [ fd .05 if xcor >= (max-pxcor - 1) and old-xcor < (max-pxcor - 1) [ifelse day? = true [ set day? false ] [set day? true] ] ifelse day? = true [set color yellow] [set color 9] ] ask sun [ set old-xcor xcor ] end to takeup-water if random 100 < water-flow [ create-water 1 [set color blue set shape "circle" set size 2 setxy min-pxcor (- 16 - random 4) set heading 90 fd 1 ]] ask water [ if xcor > max-pxcor - 1 [die] if abs xcor < 3 and ycor < -15 and random 100 < 5 and (count water with [ycor > -5]) < 20 [set heading 0] if ycor > -7 [set water-in-leaf? true] if water-in-leaf? = true and distancexy 0 0 > 8 [ rt 180 fd 1 ] if distancexy 0 0 < 7 [set heading heading + (10 - random 20)] fd .3 ] end to set-CO2 if count CO2 < CO2-amount [ create-CO2 1 [ set shape "CO2" set size 3 setxy random max-pxcor random max-pycor set heading random 360 ] ] ask CO2 [ set heading heading + (10 - random 20) fd .5 if ycor > (max-pycor - 1) or ycor < min-pycor + 6 [ rt 180 fd 1 ] ] end to photosynthesize ask chloroplast [ if NADPH? = false and count (light in-radius 2) > 0 and count (water in-radius 2) > 0 [ set NADPH? true set size 5 set color orange set O2-temp-count O2-temp-count + 1 ask one-of (water in-radius 2) [ beep die ] ask one-of (light in-radius 2) [ beep die ] ] If NADPH? = true and count (CO2 in-radius 2) > 0 and count (water in-radius 2) > 0 [ ask one-of (CO2 in-radius 2) [ beep die] ask one-of (water in-radius 2) [ beep die ] set sugar-temp-count sugar-temp-count + 1 set vapor-temp-count vapor-temp-count + 1 set NADPH? false set size 4 set color 64 ] ] end to make-oxygen if O2-temp-count > 0 [ create-oxygen 1 [set color gray + 1 set shape "oxygen" set size 2 set heading random 360 ] set O2-temp-count O2-temp-count - 1 ] end to make-sugar if sugar-temp-count > 0 [ create-sugar 1 [setxy 0 0 set shape "sugar" set color white set size 2 set heading 180 ] set sugar-temp-count sugar-temp-count - 1 ] end to make-water-vapor if vapor-temp-count > 0 [ create-vapor 1 [setxy 0 0 set shape "vapor" set color blue + 2 set size 2 set heading random 360 ] set vapor-temp-count vapor-temp-count - 1 ] end to color-sky if step mod 10 = 0 [ ask patches [ if pycor > -15 [set pcolor (scale-color blue (count light) -30 60)] ] ] end to plot-stuff set-current-plot "Production Rates" set-current-plot-pen "oxygen" plot count oxygen set-current-plot-pen "Sugar" plot count sugar ;; set-current-plot-pen "Vapor" ;; plot count vapor end @#$#@#$#@ GRAPHICS-WINDOW 276 10 614 369 20 20 8.0 1 10 1 1 1 0 1 1 1 -20 20 -20 20 1 1 1 ticks CC-WINDOW 5 383 623 478 Command Center 0 BUTTON 30 61 96 94 Reset setup NIL 1 T OBSERVER NIL NIL NIL NIL BUTTON 22 19 100 52 Run/Stop go T 1 T OBSERVER NIL NIL NIL NIL SLIDER 141 103 254 136 water-flow water-flow 0 20 10 1 1 NIL HORIZONTAL SLIDER 137 59 253 92 CO2-amount CO2-amount 0 30 14 1 1 NIL HORIZONTAL SLIDER 138 14 257 47 sun-brightness sun-brightness 0 100 36 1 1 NIL HORIZONTAL PLOT 7 142 264 320 Production Rates NIL NIL 0.0 100.0 0.0 4.0 true true PENS "Sugar" 4.0 0 -2674135 true "Oxygen" 4.0 0 -16777216 true "Vapor" 4.0 0 -13345367 false SWITCH 15 331 124 364 day-night? day-night? 1 1 -1000 TEXTBOX 136 335 248 363 Turns on the day-night cycle 11 0.0 1 @#$#@#$#@ WHAT IS IT? ----------- This is a model of photosynthesis in a chloroplast which is inside a leaf. It was written for grades 5-6. This model is used by the Concord Consortium in the UDL (Universal Design for Learning) project. To see the model in the context of an activity, go to http://udl.concord.org. Find the Intermediate Plants Unit (Grades 56) and go to the activity called "Photosynthesis: the big picture". HOW IT WORKS ------------ The following inputs can be adjusted with sliders: -- light rays radiating from the sun (yellow arrowheads) -- water supplied to the stem (blue circles) -- carbon dioxide (CO2) molecules in the atmosphere (orange and black) In the center of the leaf are several black circles representing chloroplasts. The rules for the model are as follows: 1. Water in the stem is drawn up into the leaf as it goes by, up to a maximum of 30 water molecules. 2. If a light ray and a water molecule are both inside a chloroplast, it goes into an excited state (NADPH). The circle gets larger and turns orange. One water is used up and one oxygen (gray circle) is created. 3. If a CO2 and a water are both inside a chloroplast when it is in an excited state, it returns to an unexcited state. The circle gets smaller and turns black. One CO2 is used up and one sugar (white jagged shape) is created. 4. The sugars go down the leaf stem and disappear. The idea is that they are being used by the plant in some way Ð to build leaves, stems, roots, and seeds for instance. The sugar production rate on the graph is the number of sugars on the screen at any moment. 5. The oxygens go out in all directions and disappear when they get to the edge of the screen. The oxygen production rate on the graph is the number of oxygens on the screen at any moment. HOW TO USE IT ------------- Run the model and watch for the reactions that are described above. Slow the model down if that is helpful. Water, carbon dioxide in the air, and sunlight can be controlled with the sliders. Also, the day-night switch moves the sun across the sky and changes it into a moon on the next crossing, imitating a day-night cycle. THINGS TO NOTICE ---------------- Notice that there are two reactions needed to make sugar. The first one is energy-dependent (#2 above); the second is energy-independent (#3 above). So a leave can continue to make sugar for a while after the sunlight goes away, but soon it runs out of excited-state chloroplasts and stops making sugar. THINGS TO TRY ------------- Change each of the sliders in turn and see what effect they have on the production of sugar. EXTENDING THE MODEL ------------------- This model includes only the main inputs and final products of the photosynthesis reaction, which is very complex. One could try to expand the reactions that are included in the model. Think of a better way to graph rates of production. Figure out how to make the graph smoother. Have the leaf do something (grow?) in response to the production of sugar. Have it turn brown if water is turned off for too long. The photosynthesis reaction is not linear; it also has an initial threshold. Figure out how to add this to the model. NETLOGO FEATURES ---------------- Note that the image "aspenleaftrans.png" must be in the same folder as the model in order to be displayed. This image underlies but does not interact with the model. RELATED MODELS -------------- A related model, "leaf-micro.nlogo", looks at the same process but with a slightly different presentation. It is also posted on Community Models. CREDITS AND REFERENCES ---------------------- This model was written by Edmund Hazzard as part of the Universal Design for Learning Project (UDL) at the Concord Consortium (http://www.concord.org) in March of 2008. @#$#@#$#@ default true 0 Polygon -7500403 true true 150 5 40 250 150 205 260 250 airplane true 0 Polygon -7500403 true true 150 0 135 15 120 60 120 105 15 165 15 195 120 180 135 240 105 270 120 285 150 270 180 285 210 270 165 240 180 180 285 195 285 165 180 105 180 60 165 15 arrow true 0 Polygon -7500403 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150 box false 0 Polygon -7500403 true true 150 285 285 225 285 75 150 135 Polygon -7500403 true true 150 135 15 75 150 15 285 75 Polygon -7500403 true true 15 75 15 225 150 285 150 135 Line -16777216 false 150 285 150 135 Line -16777216 false 150 135 15 75 Line -16777216 false 150 135 285 75 bug true 0 Circle -7500403 true true 96 182 108 Circle -7500403 true true 110 127 80 Circle -7500403 true true 110 75 80 Line -7500403 true 150 100 80 30 Line -7500403 true 150 100 220 30 butterfly true 0 Polygon -7500403 true true 150 165 209 199 225 225 225 255 195 270 165 255 150 240 Polygon -7500403 true true 150 165 89 198 75 225 75 255 105 270 135 255 150 240 Polygon -7500403 true true 139 148 100 105 55 90 25 90 10 105 10 135 25 180 40 195 85 194 139 163 Polygon -7500403 true true 162 150 200 105 245 90 275 90 290 105 290 135 275 180 260 195 215 195 162 165 Polygon -16777216 true false 150 255 135 225 120 150 135 120 150 105 165 120 180 150 165 225 Circle -16777216 true false 135 90 30 Line -16777216 false 150 105 195 60 Line -16777216 false 150 105 105 60 car false 0 Polygon -7500403 true true 300 180 279 164 261 144 240 135 226 132 213 106 203 84 185 63 159 50 135 50 75 60 0 150 0 165 0 225 300 225 300 180 Circle -16777216 true false 180 180 90 Circle -16777216 true false 30 180 90 Polygon -16777216 true false 162 80 132 78 134 135 209 135 194 105 189 96 180 89 Circle -7500403 true true 47 195 58 Circle -7500403 true true 195 195 58 circle false 0 Circle -7500403 true true 0 0 300 circle 2 false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 circle-edge true 14 Circle -16777216 false true 12 12 277 Circle -16777216 false true 21 21 258 Circle -16777216 false true 23 23 255 Circle -16777216 false true 30 30 240 co2 true 0 Circle -955883 true false 26 116 67 Circle -955883 true false 26 116 67 Circle -955883 true false 191 116 67 Circle -7500403 false true 75 75 150 Circle -16777216 true false 101 101 67 Circle -16777216 true false 73 73 152 Circle -955883 false false 18 108 85 Circle -955883 false false 183 108 85 cow false 0 Polygon -7500403 true true 200 193 197 249 179 249 177 196 166 187 140 189 93 191 78 179 72 211 49 209 48 181 37 149 25 120 25 89 45 72 103 84 179 75 198 76 252 64 272 81 293 103 285 121 255 121 242 118 224 167 Polygon -7500403 true true 73 210 86 251 62 249 48 208 Polygon -7500403 true true 25 114 16 195 9 204 23 213 25 200 39 123 cylinder false 0 Circle -7500403 true true 0 0 300 dot false 0 Circle -7500403 true true 90 90 120 face happy false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 255 90 239 62 213 47 191 67 179 90 203 109 218 150 225 192 218 210 203 227 181 251 194 236 217 212 240 face neutral false 0 Circle -7500403 true true 8 7 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Rectangle -16777216 true false 60 195 240 225 face sad false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 168 90 184 62 210 47 232 67 244 90 220 109 205 150 198 192 205 210 220 227 242 251 229 236 206 212 183 fish false 0 Polygon -1 true false 44 131 21 87 15 86 0 120 15 150 0 180 13 214 20 212 45 166 Polygon -1 true false 135 195 119 235 95 218 76 210 46 204 60 165 Polygon -1 true false 75 45 83 77 71 103 86 114 166 78 135 60 Polygon -7500403 true true 30 136 151 77 226 81 280 119 292 146 292 160 287 170 270 195 195 210 151 212 30 166 Circle -16777216 true false 215 106 30 flag false 0 Rectangle -7500403 true true 60 15 75 300 Polygon -7500403 true true 90 150 270 90 90 30 Line -7500403 true 75 135 90 135 Line -7500403 true 75 45 90 45 flower false 0 Polygon -10899396 true false 135 120 165 165 180 210 180 240 150 300 165 300 195 240 195 195 165 135 Circle -7500403 true true 85 132 38 Circle -7500403 true true 130 147 38 Circle -7500403 true true 192 85 38 Circle -7500403 true true 85 40 38 Circle -7500403 true true 177 40 38 Circle -7500403 true true 177 132 38 Circle -7500403 true true 70 85 38 Circle -7500403 true true 130 25 38 Circle -7500403 true true 96 51 108 Circle -16777216 true false 113 68 74 Polygon -10899396 true false 189 233 219 188 249 173 279 188 234 218 Polygon -10899396 true false 180 255 150 210 105 210 75 240 135 240 house false 0 Rectangle -7500403 true true 45 120 255 285 Rectangle -16777216 true false 120 210 180 285 Polygon -7500403 true true 15 120 150 15 285 120 Line -16777216 false 30 120 270 120 leaf false 0 Polygon -7500403 true true 150 210 135 195 120 210 60 210 30 195 60 180 60 165 15 135 30 120 15 105 40 104 45 90 60 90 90 105 105 120 120 120 105 60 120 60 135 30 150 15 165 30 180 60 195 60 180 120 195 120 210 105 240 90 255 90 263 104 285 105 270 120 285 135 240 165 240 180 270 195 240 210 180 210 165 195 Polygon -7500403 true true 135 195 135 240 120 255 105 255 105 285 135 285 165 240 165 195 line true 0 Line -7500403 true 150 0 150 300 line half true 0 Line -7500403 true 150 0 150 150 link true 0 Line -7500403 true 150 0 150 300 link direction true 0 Line -7500403 true 150 150 30 225 Line -7500403 true 150 150 270 225 oxygen true 0 Circle -7500403 true true 5 65 170 Circle -7500403 true true 125 65 170 pentagon false 0 Polygon -7500403 true true 150 15 15 120 60 285 240 285 285 120 person false 0 Circle -7500403 true true 110 5 80 Polygon -7500403 true true 105 90 120 195 90 285 105 300 135 300 150 225 165 300 195 300 210 285 180 195 195 90 Rectangle -7500403 true true 127 79 172 94 Polygon -7500403 true true 195 90 240 150 225 180 165 105 Polygon -7500403 true true 105 90 60 150 75 180 135 105 plant false 0 Rectangle -7500403 true true 135 90 165 300 Polygon -7500403 true true 135 255 90 210 45 195 75 255 135 285 Polygon -7500403 true true 165 255 210 210 255 195 225 255 165 285 Polygon -7500403 true true 135 180 90 135 45 120 75 180 135 210 Polygon -7500403 true true 165 180 165 210 225 180 255 120 210 135 Polygon -7500403 true true 135 105 90 60 45 45 75 105 135 135 Polygon -7500403 true true 165 105 165 135 225 105 255 45 210 60 Polygon -7500403 true true 135 90 120 45 150 15 180 45 165 90 square false 0 Rectangle -7500403 true true 30 30 270 270 square 2 false 0 Rectangle -7500403 true true 30 30 270 270 Rectangle -16777216 true false 60 60 240 240 star false 0 Polygon -7500403 true true 151 1 185 108 298 108 207 175 242 282 151 216 59 282 94 175 3 108 116 108 sugar true 15 Polygon -1 true true 75 60 135 15 165 60 255 60 225 120 285 165 195 180 240 255 150 255 135 210 75 255 75 210 15 195 105 150 15 90 90 75 75 60 target false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 Circle -7500403 true true 60 60 180 Circle -16777216 true false 90 90 120 Circle -7500403 true true 120 120 60 tree false 0 Circle -7500403 true true 118 3 94 Rectangle -6459832 true false 120 195 180 300 Circle -7500403 true true 65 21 108 Circle -7500403 true true 116 41 127 Circle -7500403 true true 45 90 120 Circle -7500403 true true 104 74 152 triangle false 0 Polygon -7500403 true true 150 30 15 255 285 255 triangle 2 false 0 Polygon -7500403 true true 150 30 15 255 285 255 Polygon -16777216 true false 151 99 225 223 75 224 truck false 0 Rectangle -7500403 true true 4 45 195 187 Polygon -7500403 true true 296 193 296 150 259 134 244 104 208 104 207 194 Rectangle -1 true false 195 60 195 105 Polygon -16777216 true false 238 112 252 141 219 141 218 112 Circle -16777216 true false 234 174 42 Rectangle -7500403 true true 181 185 214 194 Circle -16777216 true false 144 174 42 Circle -16777216 true false 24 174 42 Circle -7500403 false true 24 174 42 Circle -7500403 false true 144 174 42 Circle -7500403 false true 234 174 42 turtle true 0 Polygon -10899396 true false 215 204 240 233 246 254 228 266 215 252 193 210 Polygon -10899396 true false 195 90 225 75 245 75 260 89 269 108 261 124 240 105 225 105 210 105 Polygon -10899396 true false 105 90 75 75 55 75 40 89 31 108 39 124 60 105 75 105 90 105 Polygon -10899396 true false 132 85 134 64 107 51 108 17 150 2 192 18 192 52 169 65 172 87 Polygon -10899396 true false 85 204 60 233 54 254 72 266 85 252 107 210 Polygon -7500403 true true 119 75 179 75 209 101 224 135 220 225 175 261 128 261 81 224 74 135 88 99 vapor true 0 Circle -1 true false 63 198 85 Circle -1 true false 78 3 85 Circle -7500403 true true 48 33 234 wheel false 0 Circle -7500403 true true 3 3 294 Circle -16777216 true false 30 30 240 Line -7500403 true 150 285 150 15 Line -7500403 true 15 150 285 150 Circle -7500403 true true 120 120 60 Line -7500403 true 216 40 79 269 Line -7500403 true 40 84 269 221 Line -7500403 true 40 216 269 79 Line -7500403 true 84 40 221 269 x false 0 Polygon -7500403 true true 270 75 225 30 30 225 75 270 Polygon -7500403 true true 30 75 75 30 270 225 225 270 @#$#@#$#@ NetLogo 4.0 @#$#@#$#@ @#$#@#$#@ @#$#@#$#@ @#$#@#$#@ @#$#@#$#@ default 0.0 -0.2 0 0.0 1.0 0.0 1 1.0 0.0 0.2 0 0.0 1.0 link direction true 0 Line -7500403 true 150 150 90 180 Line -7500403 true 150 150 210 180 @#$#@#$#@