Final answer:
The function of a carbohydrate is to store short-term energy, particularly in the form of polysaccharides like glycogen in animals and starch in plants, which serve as quickly mobilizable energy reserves.
Step-by-step explanation:
The function of a carbohydrate is to store short-term energy. Carbohydrates, which include sugars and starches, are composed mainly of carbon, hydrogen, and oxygen. These biological molecules play a critical role in energy storage and provision for living organisms. When energy from the sun is captured through photosynthesis, it is converted into chemical energy in the bonds of glucose. This glucose can then be broken down in various pathways, including cellular respiration, to produce ATP, the primary energy currency of cells.
In the form of polysaccharides like glycogen in animals and starch in plants, carbohydrates serve as energy reserves that can be quickly mobilized to meet immediate energy demands. Additionally, other complex carbohydrates like cellulose and chitin are essential for providing structural support in plants and some animals, respectively. Carbohydrates are also involved in other biological roles such as immune function and cell-cell recognition but those functions pertain to more specific types of carbohydrates rather than their general role in energy storage.