1.5 Genetic Mutations and Inheritance
From Gametes to Zygote
Where Does Cancer Fit In?
Not all mutations will be passed on to the next generation. A mutation in a normal body cell (any kind except specialized sex cells) can result in cancer. Cancer is a term used to describe uncontrolled cell division.
The following table compares normal cells to cancer cells:
|
Normal Body Cells |
Cancer Cells | |
|---|---|---|
|
Controls on Cell Growth |
receive signals from surrounding cells, and then they stop growing |
don't receive the same signals, so they don't stop growing and dividing. Inside these cells' nuclei, chromosomes don't divide as they should. |
|
Division of DNA |
mitosis occurs normally, and DNA is divided equally between newly-formed cells |
inside these cells' nuclei, chromosomes don't divide as they should |
|
Specialization |
specialized depending on where they are located in the body (for example cells that line the small intestine are specialized for absorption of nutrients |
not specialized, so they don't perform the same function as the cells around them (for example cancer cells in the small intestine do not participate in absorption) |
|
Tumors |
do not form tumors |
fed by blood vessels, which can cause tumors to grow faster |
There are many different types of cancers, and their severity depends on where they are located. For example, a young person diagnosed with thyroid cancer can undergo surgery, radiation and hormone treatments. This type of cancer has a high survival rate. Other cancers, such as brain cancer, have much lower rates of survival.