Answer:
immune system
Explanation:
The adaptive immune system reacts specifically to pathogens (germs). It is able to recognize attacking pathogens and fights against certain antigens or foreign substances. The next time a known antigen is encountered, the adaptive immune system can respond faster.
The answer is ecological
niche. A species carving of its ecological niche is dependent on the distribution of
resources in the environment and its competitors. It begins with behavioral adaptations. A species niche includes its nutrition, relationship with other species in the ecosystem, and habitat. There
are two types of niches; realized niche (niche acquired when there is competition)
and fundamental niche (niche acquired even without competition).
The sun enters as energy and then the energy that leaves the chain exists as heat energy
The green house effect makes it possible for life to exist on earth