Tag: biology

Saccharin is a artificial sweetener. It is thermostable and remains inert at high temperature. It was discovered in 1879. It helps to control weight and its good for diabetes patients. It was used as sugar substitute in place of sucrose. It has been discontinued because it was considered a carcinogenic agent by FDA.

p53 is a protein is known as  "guardian of genome" because it regulates cellular apoptosis and cellular growth to maintain the integrity of the human genome. It is also known as policeman of oncogenes because it suppresses the mutation and prevents oncogenesis.

Tumour promotion is a process in which an existing tumour is stimulated to grow. The tumour promoter is defined as a chemical, a complex of chemicals, or a biological agent that promotes a later stage of carcinogenesis, called tumour promotion by altering transcription (expression of the genetic information) rather than altering the structure of DNA. A tumour promoter is not involved in the formation of a new tumour.

Lung cancer, also known as lung carcinoma is a malignant lung tumour characterized by uncontrolled cell growth in tissues of the lung. Most cancers which start in the lungs, known as primary lung cancers are carcinomas. Chromium fluoride is a carcinogenous hexavalent chromium which is found in the tap water. It increases the risk of lung cancer, kidney cancer, intestinal cancer etc.

An oncogene is a gene that has the potential to cause cancer. In tumour cells, they are often mutated or expressed at high levels. Activated oncogenes can cause those cells designated for apoptosis (programmed cell death) to survive and proliferate instead. Most oncogenes began as proto-oncogenes which are normal genes involved in cell growth and proliferation or inhibition of apoptosis.

A carcinogen is any substance or radiation that promotes carcinogenesis, the formation of cancer.  Carcinogens may increase the risk of cancer by altering cellular metabolism or damaging DNA directly in cells. N-nitrosodimethylene causes liver cancer, whereas some of the tobacco-specific nitrosamines cause lung cancer. Volatile N-nitrosamines induce tumours in a variety of human organs, including the tongue, oesophagus, lung, pancreas, liver, kidney and bladder. 

Cancerous cells spread to other parts of the body as it is able to break away from the original (primary) tumour and get into the bloodstream or lymph system, which can carry them to another part of the body. Cancerous cells also spread through metastasis. Metastasis is the development of secondary malignant growths at a distance from a primary site of cancer. When tumour cells metastasize, the new tumour is called a secondary or a metastatic tumour, and its cells are similar to those in the original or primary tumour.

• Cervical cancer is cancer arising from the cervix. It is due to the abnormal growth of cells that have the ability to invade or spread to other parts of the body. It is caused by Human Papillomavirus
  
• Initially, no symptoms are seen. Later symptoms may include abnormal vaginal bleeding, pelvic pain, or pain during sexual intercourse.
  
• Hence Cervical cancer is caused by Human Papillomavirus.
• So, the correct answer is 'Human Papillomavirus'.

In nuclear leakage, apart from the damage caused by fires and explosions, accidents also release radioactive materials which can cause radiation sickness. The radiation possesses carcinogenic potential. It will induce cancer in tissues of most species at all ages including the fetus. Nuclear waste is hazardous for tens of thousands of years.