Xerophytes have adapted to photosynthesise under extreme heat and light conditions through several mechanisms. Firstly, their leaves or stems, which are the primary sites of photosynthesis, often have a reflective surface. This reflective surface, created by a waxy or hairy layer, helps to deflect some of the incoming sunlight, thereby reducing the internal temperature of the plant and preventing overheating. Secondly, many xerophytes utilise a specialised form of photosynthesis known as Crassulacean Acid Metabolism (CAM). In CAM photosynthesis, the stomata open during the cooler night hours to minimise water loss. Carbon dioxide is absorbed at night and stored as malic acid, which is then used during the day for photosynthesis. This mechanism allows the plant to conserve water while still maintaining the necessary photosynthetic activity.

The root systems of hydrophytes are significantly different from those of terrestrial plants, primarily due to the contrasting environmental conditions. In hydrophytes, the roots are generally reduced in size and complexity as they do not need to search for water in the soil. These roots mainly serve as anchors to keep the plant in place in the aquatic substrate. Moreover, because oxygen is less available in water-saturated soil, the roots of hydrophytes are often adapted to absorb oxygen directly from the water. This is achieved through the presence of specialised structures like air channels (aerenchyma) which facilitate the transport of oxygen from the water or air to the root system. In contrast, terrestrial plant roots are more extensive and complex, designed for actively seeking out and absorbing water and nutrients from the soil.

Hydrophytes are primarily adapted to aquatic environments, and their survival in non-aquatic environments is generally limited. However, some hydrophytes can survive in non-aquatic conditions temporarily if they have certain adaptations. For instance, some hydrophytes can tolerate brief periods of drought or water scarcity by reducing their metabolic activities and entering a state of dormancy. During this period, they conserve energy and resources until favourable conditions return. Additionally, some floating hydrophytes can survive if stranded on moist soil, as long as their roots can access sufficient moisture. However, for most hydrophytes, prolonged exposure to non-aquatic environments would lead to desiccation and death due to their adaptations being specifically tailored for life in water-rich habitats.

Several examples of xerophytic plants illustrate their specific adaptations to dry environments. The Cactus is a classic example, with its thick, fleshy stems that store water and its spines, which are modified leaves that reduce water loss and provide shade. Another example is the Aloes, which have succulent leaves with a thick cuticle and high water-storing capacity. The leaves also contain compounds that reduce transpiration. The Joshua Tree, a type of Yucca, has deep and extensive root systems that tap into underground water sources, and its leaves are narrow and tough, minimising water loss. These adaptations enable these plants to survive and even thrive in some of the harshest and driest climates on Earth.

Hydrophytes that live in flowing water, such as streams and rivers, often have flexible stems and leaves. This flexibility is crucial for several reasons. First, it allows these plants to bend and sway with the water currents, reducing the risk of physical damage from strong flows or waves. Second, the movement with the water flow can help in the dispersal of seeds and spores, aiding in the plant's reproductive process. Moreover, flexibility can also enhance the gas exchange process by constantly moving the plant parts, thereby exposing different areas to the water's surface. This movement ensures more efficient absorption of nutrients and gases dissolved in the water. In addition, flexible structures help in avoiding the accumulation of sediments on the plant, which could otherwise hinder photosynthesis and gas exchange.