* 07/16/96 Photosynthesis 光合作用 香港道教聯合會青松中學 吳友強 2018/12/8 *

Where does photosynthesis occur？ * 07/16/96 Quick Revision : Where does photosynthesis occur？ Leaf 葉片 X-section 橫切面 : Palisade mesophyll 柵狀葉肉 電子顯微鏡下的葉綠體 Chloroplast under electron microscope Chloroplast葉綠體 2018/12/8 *

* 07/16/96 Warm-up Questions The following microphotograph is a transverse section of a A. stem. B. leaf. C. root. 2018/12/8 *

Sorry, you’ve got the wrong answer!!! * 07/16/96 Sorry, you’ve got the wrong answer!!! Can you find cortex (皮層), which is very obvious in a cross-section of a stem ? Try again... 2018/12/8 *

Sorry, you’ve got the wrong answer!!! * 07/16/96 Sorry, you’ve got the wrong answer!!! Are the vascular bundles(維管束) concentrated in the centre of the section ? Try again... 2018/12/8 *

Congratulations!!! You’ve got the correct answer!!! Go to next * 07/16/96 Congratulations!!! You’ve got the correct answer!!! Go to next question... 2018/12/8 *

* 07/16/96 Warm-up Questions Here is a transverse section of a leaf. It is a leaf of A. monocotyledonous xerophyte B. dicotyledonous hydrophyte C. dicotyledonous mesophyte 2018/12/8 *

Sorry, you’ve got the wrong answer!!! * 07/16/96 Sorry, you’ve got the wrong answer!!! Xerophyte is a kind of plants adapted in desert habitat. Try again... 2018/12/8 *

Sorry, you’ve got the wrong answer!!! * 07/16/96 Sorry, you’ve got the wrong answer!!! Hydrophyte is a kind of plants adapted in aquatic habitat. Try again... 2018/12/8 *

Congratulations!!! You’ve got the correct answer!!! Bonus ……. * 07/16/96 Congratulations!!! You’ve got the correct answer!!! Bonus ……. 2018/12/8 *

Give two reasons to support your answer. Hints ----- * 07/16/96 Bonus : Give two reasons to support your answer. Hints ----- ??? 2018/12/8 *

Definition of Photosynthesis * 07/16/96 Definition of Photosynthesis Photosynthesis is a process by which green plants use sunlight trapped by chlorophyll to produce organic compounds (carbodyrate) from carbon dioxide and water, oxygen is released as by-product. 2018/12/8 *

Summary of Photosynthesis * 07/16/96 Summary of Photosynthesis Sunlight 陽光 Carbon dioxide 二氧化碳 Water 水 Chlorophyll 葉綠素 Oxygen 氧 Glucose 葡萄糖 2018/12/8 *

Experiments : 1.To show that starch is produced during Photosynthesis. * 07/16/96 Experiments : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll 1.To show that starch is produced during Photosynthesis. 2018/12/8 *

Four steps : 1.Boil the leaf in water, why ? * 07/16/96 Four steps : 1.Boil the leaf in water, why ? 2.Boil the leaf in alcohol, why ? 3.Wash the leaf in warm water, why ? 4.Add iodine solution to the leaf, what is the expected result ? 2018/12/8 *

Experiments : Aim : Control : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 * 07/16/96 Experiments : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll Aim : To show that light is necessary for Photosynthesis. Control : Do we need a Control for this experiment ? 2018/12/8 *

Experiments : Aim : Control : Any Assumption ? light * 07/16/96 Experiments : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll Aim : To show that chlorophyll is necessary for photosynthesis. Control : Do we need a Control for this experiment ? Any Assumption ? 2018/12/8 *

Experiments : Aim : Any Criticism on the set-up ? * 07/16/96 Experiments : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll Aim : To show that carbon dioxide is necessary for photosynthesis. Any Criticism on the set-up ? (Think about Variables.) 2018/12/8 *

Is it better ? light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll 2018/12/8 * 07/16/96 light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll Is it better ? 2018/12/8 *

Experiments : Aim : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll * 07/16/96 Experiments : light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll Aim : To show that oxygen is produced during photosynthesis. 2018/12/8 *

Logics In an experiment, think about : Aim and objective * 07/16/96 Logics In an experiment, think about : Aim and objective Control experiment Dependent variables Independent variables Assumptions Limitations 2018/12/8 *

Limitations of the summary equation : * 07/16/96 Limitations of the summary equation :　　 light 6CO2 ＋ 6H2O C6H12O6 + 6O2 chlorophyll 1.Photosynthesis is a two phase process, which cannot be shown in the equation. 2.Source of oxygen cannot be shown. 3.Glucose is not the first product of photosynthesis. 2018/12/8 *

Photosynthesis involves two stages : * 07/16/96 Photosynthesis involves two stages : Light reaction light is necessary light split water into hydrogen and oxygen Dark reaction light is not necessary hydrogen is used to reduce carbon dioxide to carbodyrate 2018/12/8 *

Light reaction Light 陽光 Water 水 Oxygen 氧 Hydrogen氫 （原子） Chlorophyll * 07/16/96 Light reaction Light 陽光 Water 水 Oxygen 氧 Hydrogen氫 （原子） Chlorophyll 葉綠素 Released from the plant Dark reaction 2018/12/8 *

Dark reaction Hydrogen氫 （原子） Carbohydrate 碳水化合物 Carbon dioxide 二氧化碳 * 07/16/96 Dark reaction Hydrogen氫 （原子） Carbohydrate 碳水化合物 Carbon dioxide 二氧化碳 2018/12/8 *

This powerpoint was kindly donated to www.worldofteaching.com * 07/16/96 This powerpoint was kindly donated to www.worldofteaching.com http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching. 2018/12/8 *