100 likes | 345 Views
Photosynthesis. Man I Wu Zhuan Liang Samantha Chee. Photosynthesis. Process by which light energy is converted to chemical energy Carbon dioxide and water are the raw materials plants use in producing simple sugar Photosynthesis occurs in the leaves of plants
E N D
Photosynthesis Man I Wu Zhuan Liang Samantha Chee
Photosynthesis • Process by which light energy is converted to chemical energy • Carbon dioxide and water are the raw materials plants use in producing simple sugar • Photosynthesis occurs in the leaves of plants • Photosynthesis has two parts: the light dependent reaction and the light independent reaction
Light Dependent Reaction • When light energy is used to make ATP, it is called photophosphorylation • Photophosphorylation uses light, ADP and phosphates to make ATP • Non-cyclic photophosphorylation • Cyclic photophosphorylation
Non- cyclic photophosphorylation Produces ATP using both photosystem I and photosystem II Leaf captures sunlight, activating electrons P680 traps the activated electrons and pass down to carriers in the electron transport chain When P680 absorb light, it splits water into oxygen, hydrogen ions and electrons (process is photolysis) Proton gradient is formed during photolysis because hydrogen ions accumulate inside thylakoid as hydrogen ions move through ATP synthase, ADP and P produces ATP P700 in photosystem I captures light and passes excited electrons down an electron transport chain to produce NADPH
Cyclic photophosphorylation P700 in photosystem I captures light and passes excited electrons down an electron transport chain to produce ATP NADPH is not produced Water is not split by sunlight
Light Independent Reaction The light independent reaction is also called the Calvin Cycle. There are three phases: carbon fixation, reduction, and RuBP. 1 carbon gets added to the RuBP during Rubisco and forms 6 carbons. Then 6 ATP turns into 6 ADP and 6 NADPH turns into 6 NADP+ and 6 P. Glucose comes out and 3 ATP turns into 3 ADP. In the end it becomes RuBP again and the cycle continues. All the ADP and NADP+ then goes to the light dependent reaction and the cycle continues.