What is the function of stomata in leaves?

The function of stomata in leaves is to facilitate gas exchange, primarily the intake of carbon dioxide and release of oxygen.

Stomata are tiny openings or pores found predominantly on the underside of plant leaves. They play a crucial role in photosynthesis, a process by which plants convert light energy, usually from the sun, into chemical energy in the form of glucose. This process requires carbon dioxide, which enters the plant through the stomata.

The stomata are surrounded by two specialised parenchyma cells, known as guard cells. These cells control the opening and closing of the stomata, thereby regulating the gas exchange. When the guard cells are filled with water, they swell, causing the stomata to open. Conversely, when the guard cells lose water, they shrink, closing the stomata. This mechanism helps to prevent excessive water loss from the plant through transpiration, especially in conditions of low humidity or high temperature.

In addition to facilitating the intake of carbon dioxide, stomata also allow for the release of oxygen, a by-product of photosynthesis, into the atmosphere. This oxygen is vital for the survival of most organisms on Earth, including humans, who inhale it for respiration.

Furthermore, stomata also play a role in the process of transpiration, which helps in the transport of water and minerals from the roots to the rest of the plant. When stomata are open, water vapour escapes from the leaf, creating a negative pressure that pulls water up from the roots through the xylem, a type of vascular tissue.

In summary, stomata in leaves are essential for photosynthesis, respiration, and transpiration, making them vital for the survival and growth of plants, and indirectly, other life forms on Earth.