Single-celled animals living in fresh water possess a vacuole that contracts at regular intervals to eliminate extra water. Single-celled plants living in fresh water do not have an equivalent vacuole. Which statement explains why only these animals need this vacuole?
- APlant cell cytoplasm and animal cell cytoplasm both have a lower water potential than fresh water.
- BPlant cell sap has the same water potential as fresh water, animal cytoplasm has a lower water potential than fresh water.
- CPlant cell walls are impermeable to water, animal cell surface membranes are permeable to water.
- DPlant cell walls restrict the entry of water, animal cell membranes allow the free entry of water.