Bacteria Microbe - a tiny organism that can be seen only with a microscope. Single celled protist (or unicellular protist) are called microbes. Morphology – the branch of biology dealing with organism form and structure Cell Culture – the growth of cells in a substance (usually agar) in a controlled environment. Prokaryote - a unicellular organism that lacks a true nucleus and membrane-bound organelles. Prokaryotes are commonly called bacteria. Bacteria – Any of a large group of one-celled organisms that lack a membrane-bound nucleus. Bacterial disease – a disease caused by a bacteria (e.g. rabies) Antimicrobial Product – a substance that is designed to kill microbes before they can enter your body. Antibiotics – drugs that kill bacteria or prevent their reproduction Exposure – being introduced to a chemical or organism Dose – the amount of chemical that someone should take for the desired effect