Biology project for class 12 on cancer pdf

Cancer
definition
Cancer is not just a disease, but there is a large group of about 100 diseases. It is a genetic disease, in which there are two main characteristics of uncontrolled growth of cells in the human body, and the ability of those cells to migrate from the original site and spread to distant sites.

description
One in four deaths in the United States is from cancer. This is the second place from heart disease in the United States as a cause of death. There is a possibility of diagnosis of approximately 1.2 million American cancers every year, out of which more than 500,000 patients have been diagnosed with ill. Cancer can attack anyone as the age of people increases the incidence of cancer, most cases are seen in adults, middle-aged or old, the most common cancer skin cancer, lung cancer, colon cancer, breast In addition to cancer (in women), and prostate cancer (in men), kidneys, ovaries, uterus, pancreas, bladder, rectum, blood (leukemia) and lymph nodes (lymphoma) Nsr tend to affect most Americans who are involved in 12 major cancers.

Cancer, by definition, is a disease of gene. Gene is a small part of DNA, which is the master molecule of the cell. Gene creates proteins, which are the last workhorse cells. It is this protein, with other substances, which allows our body to operate many processes which allow people to breathe, think, move, etc. Many genes produce proteins that are involved in controlling the cell growth and division process. A change or mutation of the DNA molecule can inhibit the gene and cause defective proteins. This makes the cell unusable and loses its strength on the development. Abnormal cells begin to divide uncontrolledly and eventually known as a new development that is known as tumor or neoplasm (cancer is known as "new growth"). In a healthy person, the immune system can recognize the plastics cells and destroy them before they get a chance to divide them. However, some mutant cells can avoid immune identification and may survive to form tumors or cancers.

There are two types of tumors, are benign or fatal; A benign tumor is growing slowly, does not spread or invade nearby tissues, and is removed once, it usually does not recur. On the other hand, a malignant tumor attacks the surrounding tissues and spreads to other parts of the body. If the cancer cells have spread in the surrounding tissues, even after the primary lethal tumor is removed, it usually reuses locally or on the distant site. Due to damage to the environment of the cell, most of the cancer cells are due to the change in DNA. Environmental factors due to the initial mutation in DNA are called carcinogens, and there are several types. Some cancers also have genetic basis. In other words, a person may get faulty DNA from the patient's parents, who can guess the patient's cancer. There are also two "hit" theories, where the combination of genetic mutation and the ecological conditions cause stimulation of cell division and / or replication. Although this scientific evidence plays a role, both factors (environmental and genetic) indicate, less than 10% of all cancers are pure genetic. Cancer which is known for genetic link, it is cancer of the breast, stomach cancer, ovarian cancer and uterine cancer. At the end of 2001 scientists took a step closer to identifying genetic markers reflecting the sensitivity of cancer. It is believed that "low greased genes", these markers are considered to be an alliance to increase the risk of cancer.

There are many different types of cancer that are carcinoma cancer, which arise in epithelium (layer of cells covering the body surface and lining the internal organs and various glands) ninety percent human cancers fall into this category. Melanoma is cancer that occurs in the skin, usually in pigment cells

(Melanocytes). Taurines, which support the body's body, such as bone, muscles and blood vessels, are cancerous. Cancer of blood and lymph glands is called leukemias and lymphoma respectively. Glioma is the cancer of the nerve tissue

Causes and symptoms
Causes and risk factors
The main risk factors for cancer are: Tobacco, Alcohol, Diet, Sexual and Breeding Behavior, Infectious Agents, Family History, Business, Environment and Pollution. According to the estimates of the American Cancer Society (ACS), in 2003 about 40% of cancer deaths were due to the use of tobacco and excessive alcohol. One-third of the deaths were related to diet and nutrition. In cases of cancer of one million skin cells, due to exaggerations of ultraviolet light from the sun's rays. It should be noted that medical science is not able to solve many specific causes of cancer, but is able to estimate the risk factor and event associated with different agents.

Tobacco. Eighty-nine percent of lung cancer cases