What does morphology refer to in biology?

Morphology in biology refers specifically to the form and structure of an organism. This includes aspects such as size, shape, and arrangement of various parts of the organism, whether they are cellular structures, organs, or entire organisms. Morphology is crucial for identifying and classifying organisms, as it helps biologists understand how different species have adapted their structures to survive in their environments.

The other choices relate to different aspects of biological study. Functionality of organ systems refers to physiology, which focuses on how different systems in organisms operate and interact. Genetic makeup pertains to genetics, involving the study of an organism's DNA and hereditary information. Behavioral characteristics refer to ethology, which examines how organisms interact with one another and their environment. Understanding morphology is thus fundamental for discerning the physical characteristics of organisms, which can inform other biological fields.