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In the stems there are mainly three types of tissues present such as; dermal, vascular, and ground tissue. Each tissue has a distinct function for the development and growth of the plant.

• Dermal tissue: Mostly epidermal tissues or the outer layer

• Vascular tissue: transportation of water and minerals

• Ground tissue: support and protect the stem

Stomata is the opening pore on the leaf epidermis that helps in gaseous exchange. The stoma is surrounded by two cells known as guard cells. The opening and closing of stomata is mainly guided by the guard cell and thus ensures the uptake of carbon dioxide and in return oxygen and water are released.

If the cells like stomata and guard cells do not function properly then processes like transpiration, photosynthesis, and respiration would not take place. Excess water can not be removed from the aerial part without stomata.