A plant is like a living factory, taking in sunlight, water and air and manufacturing food in the form of energy. Each plant is adapted to its environment so that it will thrive under only the amount of sunlight, water and air that the environment provides. A plant that is moved to a new environment where water, sunlight and air quantities are different will not easily adapt to that environment and may die.
Plants are composed of a series of systems. Each of the systems relies on one another in order to work. For example, a plant's breathing is directly related to the way in which the plant will absorb water. Additionally, plants breathe using the energy they receive through photosynthesis, which relies on sunlight. If one of these functions were to stop, the rest would as well and the plant would die.
If you compare plants from two different environments, you will see that they have developed completely different structures so that they can effectively get sunlight, water and air from the environment that they live in. Even though the plant has a different method of obtaining these resources, they still utilize the resources in similar ways. For example, plants in desert climates have thick leaves so that they conserve moisture while they breathe and deep roots for obtaining moisture from deep in the soil. Plants in areas where water is abundant have shallower roots and thinner, less fleshy leaves.
Plants draw up water from their roots as they lose water during the process of breathing. When a plant breathes, it is called transpiration. The plant has a number of openings on its surface, which are known as stomata. When a plant breathes, its stomata open and it exudes oxygen and takes in carbon dioxide. During this process moisture is lost. Plants that grow in a humid environment typically undergo transpiration at a constant rate. Plants such as cactus that grow in desert climates may only undergo transpiration at night when the temperatures are cool.
As a plant loses moisture through transpiration, it absorbs more moisture at the root level. The water is transported through capillary action up strawlike cells known as xylem. Transpiration causes a plant to lose about 90 percent of the moisture that the plant takes in at the roots. The remaining 10 percent is absorbed by plant tissue and used in the process of photosynthesis.
Plants take in sunlight as a part of the photosynthesis process. As sunlight strikes the leaves, each leaf acts as a solar collector by absorbing solar radiation. The solar radiation triggers a chemical reaction in the cells of leaves that creates oxygen, starches and sugars from water and carbon dioxide.