Is being in a "habitable zone" enough to say the planet is habitable for human life? What characteristics would an Earth-like pl
anet need to have to support life? What challenges would we face traveling to and colonizing Kepler-186f, or other Earth-like planets outside of our solar system? Do you think scientists should spend time looking for Earth-like planets before we have the technology to visit them? Why or why not?
It is not. Habitable does not mean to humans but in general to life forms. It just means that <span>the range of orbits around a star within which a
planetary surface can support liquid water given sufficient atmospheric
pressure and that some form of organic life could develop, but this does mean that humans could live in them. They should definitely spend more time looking at them because the processes in those planets might be harmful to humans so humans shouldn't just try to visit them before understanding them.</span>
The ventricles of the heart have thicker muscular walls than the atria. This is because blood is pumped out of the heart at greater pressure from these chambers compared to the atria.
The generalization that all organisms are composed of cells was established through multiple observations in various kinds of animals and plants. A controlled experiment of finding cells in all the kinds of living organisms is not possible or is infeasible as it will require prior knowledge of all the kinds of organisms inhabiting Earth and the effort to catch and bring them in the controlled environment of the lab for testing.
