[Solved] A horizontal merger refers to a merger between two companies in the same industry, and serving the same markets. Specimen Testing: The analysis of a sample of body tissue or fluid to diagnose or monitor health conditions. Microscopic Examination: The analysis of small objects or structures that cannot be seen with the naked eye, using a microscope. Epithelial Cells: Cells that line the surfaces of the body, such as skin, blood vessels, urinary tract, and organs, providing protection, absorption, and secretion functions. Bacteria: Microscopic, single-celled organisms found in virtually every environment on Earth, some of which are beneficial while others can cause diseases.