Which is the best explanation for how fluid pressure from freshwater plants to stand upright?

Freshwater is a hypotonic solution, which causes the plant cells to swell because of turgor pressure

Explanation:

Fresh water is hypotonic to plant cells thus the plant cells absorbs water osmotically, the cell's vacuole enlarges, exerts an outward pressure on the cell wall called turgor pressure and becomes turgid, which keeps the plants upright.

The pressure increases as more water is taken into the vacuole which pushes the cytoplasm against the cell wall until the cell wall cannot stretch anymore. When  the cell wall is being stretched outside it develops a resistant pressure to stretching that is equal and opposite to turgor pressure called wall pressure.

b. climate change will cause an increase in biodiversity of all ecosystems.

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