Having two copies of the mutated genes cause sickle cell anemia, but having just one copy does not, and can actually protect against malaria - an example of how mutations are sometimes beneficial.
The majority of mutations have neither negative nor positive effects on the organism in which they occur. These mutations are called neutral mutations. Examples include silent point mutations. They are neutral because they do not change the amino acids in the proteins they encode.
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All of those can potentially harm the earth. Human activity is a cause of pollution, and pollution is the cause of acid rain to some extent.
The teratogens can be defined as any physical, chemical, or infections agents that have the ability to penetrate the protective layers of the embryo, and affect its viability. The overall development and the development of the different organ systems might be affected because of these teratogens. When the embryo is exposed to the teratogens after the organogenesis is complete, it is most likely that the fetus will suffer from the stunted growth. When the organogenesis is complete, the organs are already formed, and hence, no severe damage can occur to them. Down's syndrome will result if the chromosomal abnormality occur in the fetus, which is not likely after the organogenesis is already complete. Any kind of severe anatomical defects are also least likely after organogenesis is completed. Therefore, the chances of having stunted growth are high.
