Foreign invaders have proteins called antigen, which antibodies lock onto to neutralize. The foreign proteins are different from proteins in our own body, so the immune system can recognize them and finally eliminate them.
Answer:
nucleotides
Explanation:
RNA and DNA are polymers made of long chains of nucleotides.
Science<span> is the study of the nature and behavior of natural things and the knowledge that we obtain about them
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Answer:
Renewable Energy Resources.
Explanation:
Unlike fossil fuels which cannot be recovered when destroyed, these sources of energy can be recovered by a means of recycling . Recycling here reduces solid wastes which is one of the causes of land pollution.
Hydroelectric schemes can only be built in mountain regions where rainfall and rivers are plentiful which involves upset of aquatic ecosystem. This poses a dangerous pollution problem though.
Wind generators and solar panels are not very efficient energy producers. However, future schemes for producing solar energy via solar satellites are promising.
