Why did the Elodea tube revert back to a red color after being exposed to light and not the control?

Through investigation, students observe that an Elodea plant in water and exposed to light performs photosynthesis. By using an oxygen meter, students can identify an increase in the amount of dissolved oxygen in the water containing the Elodea plant. This is a product of photosynthesis.

Explanation:

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unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.