Which of the following processes directly affects the stomata of plant leaves during water deficiency?

Which of the following processes directly affects the stomata of plant leaves during water deficiency?

• A. Photosynthesis
• B. Guard cells lose turgor and collapse
• C. Increased transpiration
• D. Root absorption increases

Answer: (B)

The process that directly affects the stomata of plant leaves during water deficiency is the loss of turgor in guard cells, leading to their collapse. Stomata are small openings on the surfaces of leaves that regulate gas exchange, allowing carbon dioxide to enter for photosynthesis and water vapor to exit during transpiration. Guard cells are responsible for opening and closing these stomatal pores. When a plant experiences water deficiency, the availability of water for the guard cells diminishes. Guard cells maintain their turgor pressure by taking up water; however, in dry conditions, they lose water and therefore lose turgor. This loss causes the guard cells to become flaccid, leading to the closing of the stomata. As a result, the plant reduces water loss through transpiration, although it may also limit the intake of carbon dioxide for photosynthesis. The other processes mentioned, such as photosynthesis, increased transpiration, and root absorption, are related to plant physiology but do not directly cause the immediate physiological changes in stomatal function during water deficiency. Instead, they may contribute to the conditions that influence how plants manage water and gas exchange overall.

The process that directly affects the stomata of plant leaves during water deficiency is the loss of turgor in guard cells, leading to their collapse. Stomata are small openings on the surfaces of leaves that regulate gas exchange, allowing carbon dioxide to enter for photosynthesis and water vapor to exit during transpiration. Guard cells are responsible for opening and closing these stomatal pores.

When a plant experiences water deficiency, the availability of water for the guard cells diminishes. Guard cells maintain their turgor pressure by taking up water; however, in dry conditions, they lose water and therefore lose turgor. This loss causes the guard cells to become flaccid, leading to the closing of the stomata. As a result, the plant reduces water loss through transpiration, although it may also limit the intake of carbon dioxide for photosynthesis.

The other processes mentioned, such as photosynthesis, increased transpiration, and root absorption, are related to plant physiology but do not directly cause the immediate physiological changes in stomatal function during water deficiency. Instead, they may contribute to the conditions that influence how plants manage water and gas exchange overall.