Final answer:
Cells use energy to perform various tasks such as molecule synthesis, signal transportation, and movement. They obtain energy by metabolizing nutrients, which involves anabolic and catabolic reactions, and store it as ATP. Plants produce energy-rich sugars through photosynthesis, which are used by themselves and other organisms.
Step-by-step explanation:
How Cells Use Energy
Cells require energy for virtually all processes, including the synthesis and breakdown of molecules, transporting signals such as hormones and neurotransmitters, and motility using structures like cilia and flagella. Energy comes primarily in the form of Adenosine Triphosphate (ATP), the cellular 'currency' of energy. Cells obtain energy through the metabolism of nutrients, like sugars, which are broken down in a series of anabolic and catabolic reactions. These metabolic processes are part of a broader field known as bioenergetics, which is the study of energy flow through living systems.
During anabolic reactions, cells use energy to build complex molecules from simpler ones, whereas catabolic reactions release energy when complex molecules are broken down. Plants, for instance, capture energy from sunlight during photosynthesis to create sugars that can later be used by both plants and other organisms. Overall, cells are efficient at harnessing energy from various sources and utilizing it to maintain their structure and function.