Cancer Disease Assignment Essay
cancer is a disease that occurs when cells divide uncontrollably (Belk & Maier, 2013). During cell division- which is a regulated process where a cell divides or replicates itself, cells are required to divide when it is appropriate (Belk & Maier, 2013), cancerous cells, however, are not regulated, and this leads to a pile or lump of cells called a tumor. Tumors are mass of cells with no function in the body; they can be either benign or malignant (Belk & Maier, 2013). A benign tumor is mostly harmless as it does not affect any other part of the body, although, some benign tumors can become malignant. Malignant tumors are very dangerous, and they are the cancerous tumors, they invade surrounding tissues and can break away to a distant location different from its cancerous origin, this is called metastasis (Belk & Maier, 2013). There are no specific causes of cancer but there are risk factors that could predispose an individual to have cancer, and they include tobacco smoking which has been associated to be the cause of 90 percent of lung cancers (Belk & Maier, 2013), other risk factors are lack of exercise, obesity, excess alcohol consumption.Cancer Disease Assignment Essay
Cells divide in order to replace old and damaged cells as well reproduce new cells to help organisms grow but not all cell division leads to cancer. Some organism reproduces by asexual reproduction which is when cells produce exact copies of themselves and do not require genetic input from two parents (Belk & Maier, 2013). This kind of reproduction can be found in plants. Organisms that require genetic input from both parents reproduce in a process called sexual reproduction, and this occurs in humans (Belk & Maier, 2013). Cell division involves two processes mitosis and meiosis. In mitosis cell divide mainly for repair and growth, in meiosis to produce gametes, both occur after DNA replication and are part of the cell cycle. Mitosis is an asexual division in which parent nuclei divide to produce exact copies of daughter nuclei. Meiosis produces different copies of daughter cells during division (Belk & Maier, 2013).
There are genes responsible for maintaining regulated cell division during the cell cycle and called proto-oncogenes and tumor-suppressor genes, however, these genes can undergo mutations to become oncogenes as well as becoming unable to stop tumor cells from forming. When proto-oncogenes are mutated to become oncogenes, they overstimulate cell division which leads to the formation of cancerous cells. The tumor-suppressor cells prevent cells from the unregulated division, but when mutated it becomes unable to stop these cells from dividing, examples can be found in BRCA gene responsible for breast cancer (Blek & Maier, 2013).Cancer Disease Assignment Essay
Other factors like tobacco smoking and alcohol drinking can lead to cancer because of the presence of certain chemicals in tobacco and alcohol, these chemicals can cause rapid division of cells, prevent repair of damaged cells as well as inhibit regulated cell death called apoptosis which then leads to the formation of cancerous tumors (Belk & Maier, 2013). Furthermore, hormones like estrogen have been associated with cancer formation (Belk & Maier, 2013), obesity allows estrogen to be stored in adipose tissues which increases the chances of developing cancer.
Belk, C. M., & Maier, V. B. (2013). ). Biology: Science for Life with Physiology (4th ed.). San Francisco: Benjamin Cummings. Pearson Education Cancer Disease Assignment Essay