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what is photosynthesis

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psolaas | eNoter

Posted August 16, 2013 at 7:44 PM via web

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what is photosynthesis

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lan950s | High School Teacher | (Level 2) Adjunct Educator

Posted August 17, 2013 at 11:35 PM (Answer #4)

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Photosynthesis is an endergonic chemical reaction (one which absorbs energy) that transforms light energy (sun) into chemical energy (glucose). Remember that energy can not be created nor destroyed (only transformed). All living things need energy and photosynthesis is the process in which organisms who possess an organelle in their cells called a choloroplast can undergo which makes this cellular energy possible.

A cell's energy source originates with glucose. Another little organelle called the mitochondria will take glucose, break it down (an exergonic reaction because it releases energy), and then harnesses that energy in glucose to make a high-energy molecule called ATP. ATP fuels cells' daily activities.

Since photsynthetic organisms can not obtain glucose from "eating", they will make glucose by absorbing light energy via photosynthetic pigments called chlorophyll housed in the chloroplasts. In addition to light energy, 6 molecules of carbon dioxide, and 6 molecules of water are the reactants which yield one molecule of glucose and 6 molecules of oxygen.

The process can be broken down into the light reaction (light-dependent reaction) and dark reaction (light-independent reaction or Calvin Cycle).

During the light reaction water is split on the surface of the thylakoid membrane (the folded membrane inside the choloroplast) and the oxygen is released (hence the oxygen being a "product") while the hydrogen is retained and will be used to fuel the a membrane structure responsible for producing ATP.

That ATP will then travel to the stroma (the liquid/gel-like substance of the chloroplast) and power the dark reaction. It is here in the dark reaction where the carbon dioxide enters and undergoes a series biochemical reaction/changes and produces glucose.

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tjbrewer | Elementary School Teacher | (Level 2) Associate Educator

Posted August 16, 2013 at 10:57 PM (Answer #1)

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Photosynthesis is the process that plants, and phytoplankton use to make sugar for their own respiration. 

Plants take Carbon Dioxide `CO_(2)` and Water `H_(2)O` and expose them to light gathered by the chloroplasts, and use Chlorophyll as a catalyst.  The process stores the light energy in the chemical energy of Glucose `C_(6)H_(12)O_(6)` and release Oxygen as a byproduct. 

The balanced Chemical Equation `6CO_(2)+6H_(2)O->C_(6)H_(12)O_(6)+6O_(2)`

This is why plants and phytoplankton are called producers, they make their own food.  Consumers (including humans) consume the producers or other consumers and use the chemical energy that was stored in the consumed material. 

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MrSquid | Student , Grade 8 | eNotes Newbie

Posted August 17, 2013 at 8:46 AM (Answer #2)

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Photosynthesis is a process that is used by plants make energy.

The word formula for this: 

Carbon Dioxide + Water + Light Energy --> Oxygen + Water + Glucose

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bebars | Student , Grade 8 | eNoter

Posted August 17, 2013 at 9:16 PM (Answer #3)

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Photosynthesis Is the process in which green plants make their own food They get carbon dioxide from the air through stomata and water from the soil through their roots and use chlorophyll which is the green pigment in their leaves to capture solar energy and turn it into usable energy they use this energy to turn carbon Dioxide and water into carbohydrates (glucose). In fact, photosynthesis is a compound of two words photo means light and synthesis means production 

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