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Photosynthesis. April 23, 2014. What exactly is photosynthesis?. 2 parts: Photo = light Synthesis = to put together Using light to put together sugars (glucose) needed by organisms to produce energy What elements are involved? Oxygen, carbon, and hydrogen.
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Photosynthesis April 23, 2014
What exactly is photosynthesis? • 2 parts: • Photo = light • Synthesis = to put together • Using light to put together sugars (glucose) needed by organisms to produce energy • What elements are involved? • Oxygen, carbon, and hydrogen
Where does photosynthesis take place in plants? • Inside the leaves are smaller parts called cells • Inside these cells is a structure called the chloroplast • Inside the chloroplast are pancake like structures called grana • Inside the grana is the pigment chlorophyll that absorbs light energy and reflects the color green so they appear green
How exactly do plants make sugars? • Take in CO2 and H2O and light to make • C6H12O6 and O2 However photosynthesis is a little more complicated occurs in 2 different stages (shifts)
What are the 2 stages? • 1. light reactions – light is used to split water into hydrogen and oxygen • Hydrogen is used for the second stage and oxygen is given off as a by-product 2. Calvin cycle (dark reactions) – Hydrogen from light reactions is put together with CO2 to produce sugars light reactions occur during the day Calvin cycle occurs at night
So how does carbon dioxide and oxygen get in and out of plants? • These gases enter and leave through specialized cells called stomata which are sandwiched in between 2 guard cells that can open or close depending on what is needed • Water leaves the leaves of plant through a process called transpiration