Final answer:
Surface tension is the energy needed to increase a liquid's surface area, with water having a high surface tension due to hydrogen bonding. It helps plants transport nutrients through capillary action and allows insects to walk on water. Option D) Surface tension is the cohesion of water molecules at the surface; It supports small insects to walk on water is the correct answer.
Step-by-step explanation:
Surface Tension and Its Role in Nature
Surface tension is defined as the energy required to increase the surface area of a liquid, or the force required to increase the length of a liquid surface by a given amount. This phenomenon results from the cohesive forces among molecules at the surface of a liquid, causing it to behave as if it were covered by a stretched membrane. Among common liquids, water has a notably high surface tension, owing to the strong hydrogen bonding between its molecules. This elevated surface tension allows for various activities in nature, such as insects walking on water or a steel needle floating, thanks to the relatively solid "skin" that the water surface forms.
In the context of plants and animals, surface tension of water plays pivotal roles. For instance, capillary action, facilitated by adhesion (attraction between water molecules and other materials) and cohesion (attraction among water molecules), is responsible for water moving up from the roots to the leaves in plants. Moreover, for animals, especially small insects, surface tension supports their ability to walk on the surface of water without sinking.
The correct option that describes what surface tension is and illustrates how it is useful for plants and animals is D) Surface tension is the cohesion of water molecules at the surface; It supports small insects to walk on water.