Plants contain the carbohydrates starch and cellulose. in the spring when stem growth is at its fastest rate, cellulose production rates are increased in some plants. in the months with less sunlight, the level of starch decreased in some plants. what does this information demonstrate

Cellulose and starch are polysaccharides, that means they are made of a lot of molecules of monosaccharide or sugar, In this case this molecule is glucose which is one of the products of photosynthesis.

In photosynthesis plants take carbon dioxide from air, water from soil and energy from sunlight to produce glucose and oxygen. Glucose is used as energy storage and plants needed it to form big molecules such a cellulose or starch that make plants grow.

Taking into account that spring is a season with more sunlight, plants can take a lot of energy in order to make the reaction to obtain glucose. In season with lower sunlight, plants have low rates of photosynthesis production, and cannot make a lot of glucose molecules to form starch.  

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