What does the prefix 'ir/o' refer to in medical terminology?

The prefix 'ir/o' in medical terminology specifically refers to the iris, which is the colored part of the eye surrounding the pupil. This prefix is commonly used in contexts related to ophthalmology and the structure and function of the eye. For instance, terms like "iridotomy" (surgical incision into the iris) and "iridopathy" (disease of the iris) are derived from this prefix.

The other options do not share any connection to the prefix 'ir/o'. For instance, 'ischium' pertains to the pelvic bone, 'jejunum' refers to a portion of the small intestine, and 'potassium' is a chemical element referenced in various contexts but not related to the eye anatomy. Understanding the specific meanings associated with prefixes like 'ir/o' helps students navigate medical terminology with greater accuracy.