A tumor composed of tissues from the three embryonic germ layers. Usually found in ovary or testis. Produced experimentally in animals by injecting pluripotent stem cells to determine the stem cells’ abilities to differentiate into various types of tissues.

Tissue culture

Growth of tissue in vitro on an artificial medium for experimental research.


A method by which experimental DNA may be put into a cultured cell.


A gene that has been incorporated into a cell or organism and passed on to successive generations.


Removal of tissue from one part of the body or from one individual and its implantation or insertion into another, especially by surgery.


The outer layer of the developing blastocyst that will ultimately form the embryonic side of the placenta.


The extraembryonic tissue responsible for negotiating implantation, developing into the placenta, and controlling the exchange of oxygen and metabolites between mother and embryo.


Not having changed to become a specialized cell type.

Xenograft or xenotransplant

A graft or transplant of cells, tissues, or organs taken from a donor of one species and grafted into a recipient of another species.


A cell formed by the union of male and female germ cells (sperm and egg, respectively).

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