Which term refers to a group of atoms joined together in a particular way?

• A. Resource population
• B. Consumer population
• C. Food web
• D. Molecule

Answer: (D)

Molecules are formed when atoms join together and stay connected by chemical bonds in a specific arrangement. The term described is molecule, because it denotes a group of atoms bound together to form a single unit, whether the atoms are the same element (like O2) or different elements (like H2O). This arrangement gives the molecule its properties and function. For example, water is a molecule made of two hydrogen atoms bonded to one oxygen atom in a fixed geometry. The other terms relate to ecology or networks rather than chemical units: a resource population or consumer population refers to groups of organisms or resources within an ecosystem, and a food web is the interconnected feeding relationships among organisms.