How is a cancerous cell different from a normal cell?
Cancer is a disease characterized by the excessive and abnormal growth of certain cells. In a healthy individual, the growth of cells is balanced by the rate of cell loss. Thus, when one attains adult age, the size and cellular contents of various body organs remain constant. The balance between the growth of the cells and the rate of cell class may be dislocated by certain chemicals, physical stresses and viral agents. As a result, the normal growth of the cells may be transformed into cancerous one. Cancerous cells acquire the ability to invade new sites, a phenomenon called metastasis. They exhibit a number of alterations on cell surface, in the cytoplasm, and in their genes. These features are used for the identification of cancers.
What are the various routes by which trans-mission of human immunodeficiency virus takes place?
What are the various public health measures, which you would suggest as safeguard against infectious diseases?
What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person?
In your view what motivates youngsters to take to alcohol or drugs and how can this be avoided?
Why is that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.
Discuss with your teacher what does ‘a suitable gene' means, in the context of DNA vaccines.
Differentiate the following and give examples of each
(a)Innate and acquired immunity
(b)Active and passive immunity
The following are some well-known abbreviations, which have been used in this chapter. Expand each one to its fall form:
(a)MALT (b) CMI
(c)AIDS (d)NACO
(e)HIV
Hovy does the transmission of each of the following diseases take place?
(a)Amoebiasis (b) Malaria
(c)Ascariasis (d) Pneumonia
Do you think that friends can influence one to take alcohol/drugs? If yes, how may one protect himself/herself from such an influence?