Why does a carrot in a hypertonic solution of salt water float compared to a carrot in a hypotonic solution of salt water (which sinks)?

Cell membranes are permeable to water, and in the absence of a solute on either side of a membrane, water will move one way as easily as it moves the other. If the outside of the membrane contains a solute, such as salt, the solution correspondingly contains fewer water molecules. To restore equilibrium -- the same number of water molecules on both sides of the membrane -- water flows from inside, and the cell shrinks. On the other hand, if the concentration of solute inside the membrane is greater, water flows into the cell and swells it. This is called osmosis.The turgidity, or stiffness, of a carrot depends on the water content of its cells. When the cells are full of water, they grow large and are packed closely together, making the carrot turgid. Conversely, when the cells lose water, they shrink and the carrot shrivels. That's what happens when you put a carrot in salty water and leave it there. When the concentration of water molecules inside the cells matches that outside, the carrot stops shriveling, and when you remove it from the water and taste it, it has a stronger flavor because it contains less water

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.