Author Question: What could ultimately be linked to the lack of water on Mars? a. The large decrease in carbon ... (Read 119 times)

joblessjake · **on:** Aug 22, 2018

What could ultimately be linked to the lack of water on Mars?
a. The large decrease in carbon dioxide.
b. The proximity to the sun.
c. The lack of free oxygen in the atmosphere.
d. The lack of outgassing from the interior of the planet

Question 2

In the Insight into National Geographic Explorer, Dr. Hand suggests that studying life in extreme
environments is important for what reason?
a. It can improve our understanding of earths early evolution
b. Extreme environments have highly adapted organisms
c. These environments could mimic conditions on other planets
d. New species of organisms are being discovered

okolip · **Reply #1 on:** Aug 22, 2018

Answer to Question 1

ANS: A
The large decrease in carbon dioxide could explain why there is currently no water found on Mars.
Carbon dioxide is a greenhouse gas which can insulate a planet. As the carbon dioxide began to be
absorbed by rocks, the atmosphere became thin. This made the surface very cold. The ocean
disappeared because the water either bound to rocks or froze beneath the surface. Information can be
found in the section Are There Other Ocean Worlds

Answer to Question 2

ANS: C
It was thought that life could not exist in these harsh, dry, cold, environments but in the 70s rocks
from Antarctica had complex microbial communities of lichens and cyanobacteria. Dr. Hand explains
that studying microbes is tricky because if you bring the rocks up from the extreme environments they
often change what theyre doing. Information can be found in the section Insight from a National
Geographic Explorer