Tag: zoology

Disease that lasts for longer period of time is called chronic. Cancer is a disease caused due to abnormal growth of body cell mass.

• Palynology is the study of pollen grains and other spores, especially as found in archaeological or geological deposits. Pollen extracted from such deposits may be used for studying past climates and environments by identifying plants which are growing in a particular environment and climate.
  
• Oncology is a branch of medicine that deals with the prevention, diagnosis, and treatment of cancer. Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.
  
• Phycology or algology is a branch of life science and often is regarded as a subdiscipline of botany which involves the scientific study of algae. Algae are important as primary producers in aquatic ecosystems.
  
• Sericulture or silk farming is the cultivation of silkworms to produce silk.  Although there are several commercial species of silkworms, Bombyx mori (the caterpillar of the domesticated silk moth) is the most widely used and intensively studied silkworm.
  

An oncogene is a gene that has the potential to cause cancer. In tumor cells, oncogenes were first discovered in certain retroviruses and were identified as cancer-causing agents in many animals. In the mid 1970s, the American microbiologists, John Michael Bishop and Harold Varmus tested the theory that healthy body cells contain dormant viral oncogenes that, when triggered, cause cancer. 
Thus, the correct answer is option (D), 'J.M. Bishop and H.E. Vermus'.

Oncogenes are mutated forms of proto-oncogenes that promote cell growth. Their activation or overexpression leads to uncontrolled cell division, which is the hallmark of cancer.

Vinca  rosea is a native and endemic ornamental and medicinal plant, o source for the anticancer drugs vincristine and vinblastine.

Vitamin E is a group of eight fat-soluble compounds that include four tocopherols and four tocotrienols. It is estimated that vitamin E provides protection against carcinogens but the mechanism is not clearly understood. Gamma-tocotrienol, a cofactor found in natural vitamin E preparations, may decrease prostate tumour formation.

Cancer is a group of diseases involving abnormal and rapid cell growth with the potential to invade or spread to other parts of the body. Signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss and a change in bowel movements. Many cancers can be prevented by not smoking, maintaining a healthy weight, not drinking too much alcohol, eating plenty of vegetables, fruits and whole grains, vaccination against certain infectious diseases.

The ability to maintain functional telomeres may be one mechanism that allows cancer cells to grow in vitro for decades. Telomerase activity is necessary to preserve many cancer types and is inactive in somatic cells, creating the possibility that telomerase inhibition could selectively repress cancer cell growth with minimal side effects. If a drug or mutation can inhibit telomerase in cancer cells, the telomeres of successive generations will progressively shorten, limiting tumor growth.

Transgenic models are genetically modified organisms in which the genome has been altered through random integration of gene sequences.