ADP, ATP and Photosynthesis Copyright Cmassengale

What Is ATP? Energy used by all Cells Adenosine Triphosphate Organic molecule containing high- energy Phosphate bonds Copyright Cmassengale

Chemical Structure of ATP 3 Phosphates Ribose Sugar Adenine Base Copyright Cmassengale

What Does ATP Do for You? It supplies YOU with ENERGY! Copyright Cmassengale

How Do We Get Energy From ATP? By breaking the high- energy bonds between the last two phosphates in ATP Copyright Cmassengale

Are There Any Other Energy Molecules? YES! NAD + (Nicotinamide adenine dinucleotide, high energy state is NADH NADP + (Nicotinamide adenine dinucleotide phosphate, high energy state is NADPH FAD + (Flavin adenine dinucleotide, high energy state is FADH 2 ) Copyright Cmassengale

What do energy molecules do? They are coenzymesThey are coenzymes They carry high energy substances like H +They carry high energy substances like H + They allow respiration and photosynthesis to occur!They allow respiration and photosynthesis to occur! They are similar to ATPThey are similar to ATP Copyright Cmassengale

Photosynthesis Photosynthesis is the process of converting light energy into usable energy. Autotrophs (photosynthesizers) use light from the sun to make sugar. 6H 2 O + 6CO 2 + Light Energy  C 6 H 12 O 6 + 6O 2

Photosynthesis involves 2 steps: 1. Light DEPENDENT reaction 2. Light INDEPENDENT reaction (Calvin Cycle) The Light Reaction Takes place in the thylakoid membrane inside a chloroplast. GRANA The Chloroplast STROMA THYLAKOID

Light-dependent Reactions Overview: light energy is absorbed by chlorophyll molecules-this light energy is used to split H 2 O into H + and O 2. The hydrogen ion is then used as a high energy electron to synthesize ATP and NADPH. These will be used in the next step.

The first stage of photosynthesis captures and transfers energy. The light- dependent reactions include groups of molecules called photosystems.

Photosystem II captures and transfers energy. –chlorophyll absorbs energy from sunlight –energized electrons enter electron transport chain –water molecules are split –oxygen is released as waste –hydrogen ions are transported across thylakoid membrane

Photosystem I captures energy and produces energy-carrying molecules. –chlorophyll absorbs energy from sunlight –energized electrons are used to make NADPH –NADPH is transferred to light-independent reactions

The Light INDEPENDENT reaction (Calvin Cycle) Takes place in the stroma of the chloroplast (the goo inside the chloroplast) The energy carrying molecules, NADPH and ATP, that were made during the Light Reaction provide energy for the plant to build sugar and other compounds. The sugar that was built then goes through glycolysis and cellular respiration **Photosynthesis Animation**

Calvin Cycle (light independent or “dark” reactions) ATP and NADPH generated in light reactions used to fuel the reactions which take CO 2 and break it apart, then reassemble the carbons into glucose. Called carbon fixation: taking carbon from an inorganic molecule (atmospheric CO 2 ) and making an organic molecule out of it (glucose) This is how carbon and energy enter the food chain

I NEED TO KNOW… 1.What is ATP – why is it important 2.What are energy carrying molecules? 3.What is the equation for photosynthesis? 4.What are autotrophs/producers? 5.What is the light DEPENDENT reaction -Photosystem II and I 6.What is the light INDEPENDENT reaction? 7.What is carbon fixation?