Proto-oncogenes are:
B
A. DNA sequences in cells that are oncogenes themselves
B. Cellular copies of genes that were first found in oncogenic
retroviruses
C. DNA viral sequences that are known to infect human
cells
D. Bacterial DNA counterparts
B
A. DNA sequences in cells that are oncogenes themselves
B. Cellular copies of genes that were first found in oncogenic
retroviruses
C. DNA viral sequences that are known to infect human
cells
D. Bacterial DNA counterparts