AP BIOLOGY

Detailed explanation-1: -Panspermia requires: that organic molecules originated in space (perhaps to be distributed to Earth) that life originated from these molecules, extraterrestrially. that this extraterrestrial life was transported to Earth.

Detailed explanation-2: -According to fossil evidence, how far back in time did life on earth exist? As we discussed above, Earth formed around 4.5 billion years ago, and as per many pieces of evidence, life came into existence around 3.7 billion years ago.

Detailed explanation-3: -What makes the Earth habitable? It is the right distance from the Sun, it is protected from harmful solar radiation by its magnetic field, it is kept warm by an insulating atmosphere, and it has the right chemical ingredients for life, including water and carbon.

Detailed explanation-4: -Perhaps the most strikingly unique feature of Earth is its vast oceans, which cover 70% of the planet’s surface. Earth is the only world in our solar system with liquid water at its surface today. Scientists believe that Mars and Venus may have long ago had oceans, but these are long gone.

Detailed explanation-5: -In contrast with previous research, scientists conducted multiple tests and found that there is no life, not even microorganisms, in Dallol. One of Earth’s most extreme environments, Dallol is incredibly hot, salty and acidic.