Which-root suffix indicates related to tissues or organs?

The suffix that indicates something related to tissues or organs is "-ology." This suffix stems from the Greek word "logia," which means "study of" or "discourse." Therefore, when it is attached to a root word, it indicates the study or branch of knowledge concerning a specific subject, which can include tissues or organs. For example, "histology" is the study of tissues, and "cardiology" pertains to the study of the heart as an organ.

In contrast, "-itis" refers to inflammation (as seen in "arthritis"), "-osis" denotes a condition or disease, often of a degenerate or abnormal nature (like "neurosis"), and "-pathy" implies a disease or disorder, often used in terms of conditions affecting organs (such as "neuropathy"). While these other suffixes relate to conditions involving tissues or organs, they do not specifically denote the study or relationship to tissues and organs as "-ology" does.