Final answer:
Cancer can be viewed as a microevolutionary process because it results from genetic mutations within a cell that evolve to favor uncontrolled growth and division, leading to tumors. The key difference between malignant and benign tumors is that malignant tumors can invade and spread to other parts of the body, while benign tumors do not. Genetic mutations disrupt proto-oncogenes and tumor-suppressor genes, contributing to cancer development.
Step-by-step explanation:
Cancer as a Microevolutionary Process
Cancer is considered a microevolutionary process because it involves the accumulation of DNA mutations within a cell that lead to the development of characteristics enabling the cell to grow and divide uncontrollably. These genetic changes can lead to two common properties of cancer: 1) cells no longer respond to the usual signals that regulate the cell cycle, leading to uncontrolled cell division, and 2) they may avoid programmed cell death, or apoptosis, which eliminates damaged cells.
Another critical feature of cancerous cells is their ability to stimulate blood vessel growth, a process known as angiogenesis, which provides the tumor with nutrients and oxygen and helps cancer spread, or metastasize.