Telophase
The stage of cell division in which the recently separated chromosomes reach opposite poles of the cell. Nuclei reform and cytokinesis occurs.

Template
The single stranded nucleic acid molecule that specifies the sequence for another nucleic acid molecule synthesized by a polymerase.

Teratogenic
Substances such as chemicals or radiation that cause abnormal development of a embryo.

Testis determining factor
General term for the gene determining maleness in the human being.

Tetrad
The structure made by four sibling chromatids when homologous chromosomes pair during propose I of meiosis.
2. Four homologous chromatids (two in each chromosome of a bivalent) synapsed during first meiotic prophase and metaphase.

Tetrapod
A member of the group made up of amphibians, reptiles, birds, and mammals.

Theory
A well susbtantiated explanation of some aspect of the natural world the typically incorporates many confirmed observations, laws, and successfully verified hypotheses.

Theropod
The theropod (meaning “beast footed”) dinosaurs are a diverse group of bipedal dinosaurs. They include the largest terrestrial carnivores ever to have lived, and many quite small species. Theropods typically share a number of traits including hollow, thin walled bones and modifications of the hands and feet (3 main fingers on the hand, and 3 main (weight bearing) toes on the foot.) Most theropods had sharp, recurved teeth for eating flesh, and claws on the ends of all of the fingers and toes. Some of these characters were lost or modified in some groups later in theropod evolution. Theropod fossils are fairly rare and often fragmentary. Fossils of small theropods are especially rare, since small bones are harder to find and are weathered away easily.