When you shiver, that's actually how you help yourself stay warm! It's your immediate instinct reaction to do so when you're cold, so there will be more heat produced, and they occur by your muscles moving. =)
Answer: O many celled organisms
Explanation:
Answer:
are there any sentences to choose from
I believe its D. It becomes more difficult for the cell to get enough oxygen and nutrients.
One very specific way that humans caused changes in the atmospheric CO2 levels is the fossil fuels that the humans are burning is causing an increase in the CO2 levels. Other ways humans are doing this is by driving cars, deforestation, and an increased industrialization that releases CO2 into the atmosphere.
