Answer: Chemical bonds
Explanation: an atom has a positively charged nucleus surrounded by a cloud of electrons.
Humans aren't the only mammal that is homeothermic. There are several other mammals that are homeothermic as well. When we say homeothermic, we mean that they are able to sustain a constant body temperature regardless of the wide range of environment temperatures. Although, it's impacted within time-to-time. They are able to maintain a steady body temperature, regardless of external temperatures. If you have any questions, ask me! I hope I helped you.<span />