Question

A trace element essential for plant growth and a radioactive isotope which is used in cancer therapy is
A. Calcium
B. Iron
C. Cobalt
D. Sodium

Answer 1

Nutrients are the chemical substances utilized as raw material by plants for body building and maintenance of its functions. Micronutrients are the elements present in plant tissues in concentration of less than 10 millimole per kg.

Complete answer: Cancer is characterized by uncontrolled growth and division of cells leading to tumor formation. All the cancer causing agents are called carcinogens which may be physical, chemical, radiological or biological. On the basis of location cancers may be sarcoma, carcinoma or leukemia while on the basis of their spread these may be benign or malignant. Many cancers are curable if diagnosed and treated at early stages.
Cancer can be controlled in early stages and control depends on the location and spread of the cancer.
Radiation therapy- In this, the cancerous parts of the body are exposed to ionizing radiations like X-rays which kill the cancerous cells. This kind of cancer treatment may cause great damage to normal tissue present very close to cancerous tumour.
Hormonal therapy- In this, hormone caused cancer is treated by another hormone which neutralizes carcinogenic hormone, e.g. breast cancer can be controlled by testosterone.
Chemotherapy- A number of chemicals like 6-aminopterin, etc. inhibits DNA synthesis and division in cancer cells.
Immunotherapy- It is the latest methodology of cancer treatment in which the natural anti-cancer immunological defence mechanisms are strengthened, e.g. in radiotherapy.
So, the correct answer is “Option A”Cobalt is also used for the treatment of cancer. .

Note: Some elements like cobalt, vanadium and silicon may be essential for certain plants. Cobalt is required by plants for growth and development. It helps in the cell division and process of nitrogen fixation.