What does '-emia' refer to in medical terminology?

The suffix '-emia' is a term used in medical terminology that specifically refers to a condition related to the blood. It derives from the Greek word "haima," meaning blood. In the context of medical terms, '-emia' often appears in words describing various states or conditions affecting the blood, such as anemia (a deficiency in the number of red blood cells), leukemia (a type of cancer affecting blood cells), and hyperglycemia (an elevated glucose level in the blood). Understanding this suffix is essential for interpreting many medical terms that relate to blood conditions, allowing for a clearer understanding of diagnoses and medical discussions. The other options refer to distinct concepts: infection pertains to the presence of pathogens, bone relates to the hard connective tissue that forms the skeleton, and tissue swelling indicates inflammation or collection of fluid in tissues, none of which pertain to blood specifically.