Final answer:
Bax, an apoptosis promoter in human cells, is considered a tumor suppressor because it helps to regulate cell death and prevent the proliferation of cells that could potentially develop into cancer.
Step-by-step explanation:
The apoptosis promoter Bax normally found in human cells could be considered a tumor suppressor. Bax is part of a family of proteins that regulate cell death, or apoptosis, which is a mechanism that allows for the controlled demolition of damaged or unnecessary cells in an organism. Its role is essentially to promote apoptosis, preventing the proliferation of potential cancer cells by triggering cell death in cells that have suffered severe DNA damage or are under stress, which otherwise might lead to tumorigenesis. Therefore, it acts as a safeguard against cancer development, fitting the characteristics of a tumor suppressor.
An oncogene is a gene that in a mutated or over-expressed state can lead to the development of cancer. A proto-oncogene is a normal gene that can become an oncogene through mutation. A mitogen is a chemical substance that encourages a cell to commence cell division, leading to mitosis. Lastly, a carcinogen is any substance that promotes carcinogenesis, the formation of cancer.