If photosynthesis and cellular respiration form a cycle, why do plants need to continually take in carbon dioxide, oxygen, and water from the environment?

Oxygen is needed to break the sugar into carbon dioxide, releasing energy the plants can use to stay alive. However, plants also take in energy from the sun(light), carbon dioxide from the atmosphere, and water from the soil; they use all of them in order to make sugar, and release oxygen.

indium, and thallium have three electrons i think

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.