Stomatazellen

Stomatazellen, often referred to as guard cells, are specialized epidermal cells found in the leaves, stems, and other organs of plants. They are typically found in pairs, surrounding a pore called a stoma. The primary function of stomata is gas exchange, allowing carbon dioxide to enter the plant for photosynthesis and oxygen to exit as a byproduct. Simultaneously, stomata regulate water loss through transpiration.

The opening and closing of the stoma are controlled by changes in the turgor pressure of the stomata cells. When the stomata cells are turgid (swollen with water), they bow outwards, opening the stomatal pore. Conversely, when they become flaccid (lose water), they relax, and the pore closes. This mechanism is crucial for plant survival, enabling plants to balance the need for carbon dioxide uptake with the necessity of conserving water, especially in arid conditions.

Environmental factors such as light intensity, carbon dioxide concentration, and humidity influence stomatal aperture. For instance, stomata generally open in the presence of light to facilitate photosynthesis and close in darkness. The regulation of stomatal opening and closing is a complex process involving hormonal signals and ion transport. Stomata are vital for plant physiology, directly impacting photosynthesis, transpiration, and overall plant health.