Similar structures that are modified to work in different ways in different organisms are referred to as

Step 1: Analyze the question The question describes structures that are similar (same basic origin and plan) but modified to perform different functions in different organisms.

Step 2: Explain the concept

• Homologous structures: Structures that share the same basic anatomical plan and evolutionary origin, but may be adapted for different functions. Example: the forelimb of a human (grasping), a bat (flying), a whale (swimming), and a horse (running). All have the same bone arrangement (humerus, radius, ulna, carpals, metacarpals, phalanges). This is evidence of divergent evolution and a common ancestor.
• Analogous structures: Structures with different origins and anatomy but similar functions. Example: the wing of a bird and the wing of an insect. This results from convergent evolution.
• Divergent / convergent structures: "Divergent" and "convergent" describe types of evolution (the processes), not the standard names for the structures themselves.

Step 3: Apply to the question

• Same basic structure, different functions: this matches homologous structures.
• Analogous (B) is the opposite: different structure, same function.
• Convergent (D) is a process linked to analogous structures.
• Divergent (C) is a process linked to homologous structures. It describes how they arose, but "homologous structures" is the correct term for the structures themselves.

Step 4: Answer The correct option is A. homologous structures.

Tip: Remember it this way:

• Homologous = Heritage (same origin), different function.
• Analogous = Alike function, different origin.