Which plant cell structure is membrane bound and helps maintain water balance?

Which plant cell structure is membrane bound and helps maintain water balance?

• A. Ribosomes
• B. Golgi apparatus
• C. Endoplasmic reticulum
• D. Vacuoles

Answer: (D)

Maintaining water balance in plant cells comes from a large membrane-bound compartment called the central vacuole. It stores water and dissolved ions, and by taking in or releasing water through osmosis, it creates turgor pressure that pushes the cell membrane against the cell wall. This pressure keeps the cell rigid and helps the plant stay upright. When the vacuole is full, the cell is turgid; when it loses water, the vacuole shrinks and the plant may wilt. Other structures listed have roles in making, modifying, or transporting molecules (ribosomes for protein synthesis; Golgi apparatus for packaging; endoplasmic reticulum for synthesis and transport) and aren’t responsible for regulating water balance in the cell.

Maintaining water balance in plant cells comes from a large membrane-bound compartment called the central vacuole. It stores water and dissolved ions, and by taking in or releasing water through osmosis, it creates turgor pressure that pushes the cell membrane against the cell wall. This pressure keeps the cell rigid and helps the plant stay upright. When the vacuole is full, the cell is turgid; when it loses water, the vacuole shrinks and the plant may wilt. Other structures listed have roles in making, modifying, or transporting molecules (ribosomes for protein synthesis; Golgi apparatus for packaging; endoplasmic reticulum for synthesis and transport) and aren’t responsible for regulating water balance in the cell.