Answer: Because it is harder to draw breath in. And the cold
Explanation: At higher altitudes, it becomes more dangerous, and you can develop altitude-related illnesses such as HAPE and HACE. I read a book called<em> Into Thin Air</em>, and in the book the author goes into detail on the details/complications of climbing Mt.Everest and oxygen needs. Mountain climbers use canisters of oxygen called <u>Supplemental Oxygen.</u>
Oxygen makes up 20% of the atmosphere while nitrogen makes up 78%. The other two percent is made up of other gases. Population growth would slow. Organisms need water to survive and if there is a limited amount of water, populations will decline.
Answer:
A a nucleus
Explanation:
since prokaryotes have their DNA in the cytoplasm they do not have a nucleus
They let things in and out
