TUMORS of trophoblastic origin may arise either in the uterus or in the gonads. They are characteristically highly malignant and spread rapidly both by direct extension and by metastasis to lungs a ...

DNA (deoxyribonucleic acid) is the nucleic acid polymer that forms the genetic code for a cell or virus. Most DNA molecules consist of two polymers (double-stranded) of four nucleotides that each ...