Turgor pressure

Definition

Turgor pressure is the pressure exerted by the fluid (usually water) inside the central vacuole of a plant cell against the cell wall. This pressure helps maintain the cell's shape, supports the plant structure, and regulates growth. It is vital for maintaining cellular functions and is influenced by factors such as water availability and solute concentration.

5 Must Know Facts For Your Next Test

1. Turgor pressure helps keep plant cells firm and upright, which is essential for maintaining overall plant structure and health.
2. When a plant experiences water loss, turgor pressure decreases, causing wilting and loss of rigidity in the plant tissues.
3. Turgor pressure plays a critical role in the process of cell expansion during growth, allowing plants to increase their size.
4. In roots, turgor pressure aids in nutrient uptake from the soil, as it helps drive water and dissolved nutrients into root cells.
5. Maintaining turgor pressure is crucial for processes such as stomatal opening and closing, which regulate gas exchange in plants.

Review Questions

• How does turgor pressure affect plant cell structure and function?
  • Turgor pressure is essential for maintaining the shape and integrity of plant cells. It pushes the cell membrane against the rigid cell wall, providing support and preventing wilting. Without adequate turgor pressure, cells can become flaccid, leading to a loss of structural support for the plant as a whole and impairing its ability to carry out essential functions.
• Discuss how osmosis influences turgor pressure in plant cells.
  • Osmosis plays a key role in regulating turgor pressure by controlling the movement of water into and out of plant cells. When the surrounding environment has a lower solute concentration than the cell interior, water enters the cell through osmosis, increasing turgor pressure. Conversely, if the external environment is more concentrated, water leaves the cell, reducing turgor pressure. This dynamic balance is crucial for maintaining cell health and supporting overall plant vitality.
• Evaluate the implications of decreased turgor pressure on plant health and productivity.
  • Decreased turgor pressure can lead to serious consequences for plant health and productivity. When plants experience insufficient water uptake or increased solute concentration in their environment, turgor pressure drops. This can cause wilting, reduced photosynthesis efficiency, impaired nutrient transport, and stunted growth. In extreme cases, prolonged low turgor pressure can result in cellular damage or even death, significantly affecting agricultural yield and ecosystem stability.

Related terms

Central Vacuole: A large, membrane-bound organelle in plant cells that stores water, nutrients, and waste products, playing a crucial role in maintaining turgor pressure.

Cell Wall: A rigid outer layer that surrounds the cell membrane in plant cells, providing structural support and protection against mechanical stress.

Osmosis: The process by which water moves across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration, affecting turgor pressure.