Ex vivo
Ex vivo (Latin: "out of the living") literally means that which takes place outside an organism. In science, "ex vivo" refers to experimentation or measurements done in or on tissue from an organism in an external environment with minimal alteration of natural conditions. Testing the effect of compounds on skin biopsies is an example of ex vivo research, while isolating the primary cells from that biopsy and creating a 3D cell culture model is an example of in vitro research. Both use human tissues, but the former is a more complex and translational environment for drug testing. A  primary advantage of using "ex vivo" tissues is the ability to perform tests or measurements that would otherwise not be possible or ethical in living subjects. Tissues may be removed in many ways, including in part, as whole organs, or as larger organ systems. Examples of "ex vivo" specimen use include: The term "ex vivo" means that the samples to be tested have been extracted from the organism. The term "in vitro" (lit. "within the glass") means the samples to be tested are obtained from a repository. In the case of cancer cells, a strain that would produce favorable results , then grown to produce a control sample and the number of samples required for the number of tests. These two terms are not synonymous even though the testing in both cases is "within the glass". In cell biology, "ex vivo" procedures often involve living cells or tissues taken from an organism and cultured in a laboratory apparatus, usually under sterile conditions with no alterations, for up to 24 hours to obtain sufficient cells for the experiments. Experiments generally start after 24 hours of incubation. Using living cells or tissue from the same organism are still considered to be "ex vivo . One widely performed ex vivo" study is the chick chorioallantoic membrane (CAM) assay. In this assay, angiogenesis is promoted on the CAM membrane of a chicken embryo outside the organism (chicken).