Thymus – The lymphoid organ in which T lymphocytes are educated, mature and multiply.

T lymphocyte cells – thymus dependent cells, coordinate the cell-mediated immune system.

Transcription – constructing a mRNA molecule using a DNA molecule as a template; results in the transfer of genetic information to the mRNA.

Vaccine – Weakened or destroyed microorganisms used to help provide immunity to a certain disease or microorganism and to stimulate the production of antibodies.

Variant – a variation of a particular strain of virus or infective agent; slightly different in form or function.

Vector – anything capable of moving or transferring genetic material.

Viroid – exotic type of virus which only infects plant cells and is simply a group of naked strings of amino acids with no covering.

Virus – infectious organism that replicates itself in the cells of a host; viruses have a half alive/half dead existence and need a host to grow and reproduce.

 

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