Scientific validity is the applicability of a conclusion drawn in the context of a scientific experiment to the world at large.
Using the gas pedal analogy, the proto-oncogene would be an accelerator since they promote cell division and
deregulate apoptosis, while tumor suppressor would
be the brakes since they constrain the progress of the cell
cycle and induce cell apoptosis. An
oncogene is, therefore, when the accelerator
is stuck in down position and the brakes are not working.
3rd Choice. It describes a processed known as crossing over which results in genetically distinct daughter cells.