Comparison of the Main features of the Primary and Secondary Humoral (Antibody Mediated) Immune Responses

Feature	Immune Response
	Primary	Secondary
Type of B cells involved	Naive	Memory
Duration	4-7 days	1-3 days
Time of peak responce	10-14 days	5-7 days
Magnitude of peak response	Depends on the antigen	100 to 1,000 times higher than the primary response
Predominant antibody type produced	IgM	IgG
Antigens	Both thymus-dependent and thymus-independent	Thymus-dependent
Affinity of antibodies	Lower	Higher

There is also a debate on the safety of the use of the products of biotechnology, an area described as biosafety. Among application, on the other hand, efforts are also being made to use biotechnology to protect the environment from pollution and to conserve natural resources. At a time, when the gap between those who have plenty and those who do not have even the minimum is widening, both ends of this spectrum, i.e. plenty and poverty, are contributing to environmental degradation. It is, therefore, necessary that the developing and developed countries jointly find a path of development which meets the needs of the present without compromising the ability, of future generations to meet their needs (World Commission on Environment and Development). Efforts are being made to achieve this objective through a variety of approaches, and biotechnology is certainly one of them. In this chapter and the next four chapters, environmental; implications and applications of biotechnology for environment will be discussed.

Besides others, these applications for environment clean-up include biotreatment methods for effluents and toxic wastes (this subject is described as bioremediation and is discussed in the next). However, these bioremediation treatments, it is feared, could be problematic, where they involve deliberate or accidental release of genetically modified microbes to the environment. These applications of biotechnology in environment management.