NEET BIOLOGY

Detailed explanation-1: -An oncogene is like a gas pedal that is stuck down, which causes the cell to divide out of control. Oncogenes can be turned on (activated) in cells in different ways.

Detailed explanation-2: -The conversion of a proto-oncogene to an oncogene is called activation. Proto-oncogenes can become activated by a variety of genetic mechanisms including transduction, insertional mutagenesis, amplification, point mutations, and chromosomal translocations.

Detailed explanation-3: -Oncogenes cause cancers. Proto-oncogenes do not cause cancers. Oncogenes are coded for different proteins which change the normal cell cycle leading to uncontrolled cell division. Proto-oncogenes are coded for normal cell cycle regulator proteins.

Detailed explanation-4: -TSGs encode proteins that normally serve as a brake on cell growth. When such genes are mutated, the brake may be lifted, resulting in runaway cell growth known as cancer. In contrast, oncogenes are genes that encode proteins involved in normal cell growth.

Detailed explanation-5: -Cancer can arise when a proto-oncogene is mutated, changing it into an oncogene and causing the cell to divide and multiply uncontrollably. Some oncogenes work like an accelerator pedal in a car, pushing a cell to divide again and again.