« previous next »

Author Question: Earth's first atmosphere was rich in water vapor but poor in free oxygen. The atmosphere became more ... (Read 114 times)

Pineapplelove6

  • Hero Member
  • *****
  • Posts: 560
on: Jul 29, 2018
Earth's first atmosphere was rich in water vapor but poor in free oxygen. The atmosphere became more oxygenated with the
 
  A) development of the ozone layer.
  B) emergence of stromatolites that developed a simple version of photosynthesis.
  C) emergence of gases from volcanic eruptions.
  D) both A and B.

Question 2

What was the one most important event in the Precambrian?
 
  What will be an ideal response?


flexer1n1

  • Sr. Member
  • ****
  • Posts: 373
Reply #1 on: Jul 29, 2018
Answer to Question 1

Answer: B

Answer to Question 2

Answer: The accumulation of free oxygen in the atmosphere. This allowed the ozone layer to form and allowed life to emerge.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

You should not take more than 1,000 mg of vitamin E per day. Doses above this amount increase the risk of bleeding problems that can lead to a stroke.

Did you know?

In women, pharmacodynamic differences include increased sensitivity to (and increased effectiveness of) beta-blockers, opioids, selective serotonin reuptake inhibitors, and typical antipsychotics.

Did you know?

Eating food that has been cooked with poppy seeds may cause you to fail a drug screening test, because the seeds contain enough opiate alkaloids to register as a positive.

Did you know?

Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

Did you know?

Coca-Cola originally used coca leaves and caffeine from the African kola nut. It was advertised as a therapeutic agent and "pickerupper." Eventually, its formulation was changed, and the coca leaves were removed because of the effects of regulation on cocaine-related products.

Walruses leaving the water Walruses leaving the water
Earth as viewed from Lunar orbit during the Apollo 8 mission, Christmas Eve, 1968. Africa is at the Earth as viewed from Lunar orbit during the Apollo 8 mission, Christmas Eve, 1968. Africa is at the
A difference in oxygen content between the atmosphere and the exhaust gases enables an O2S to ... A difference in oxygen content between the atmosphere and the exhaust gases enables an O2S to ...
The fuel system should hold pressure if the system is leak free. The fuel system should hold pressure if the system is leak free.
Diversion of surface water Diversion of surface water
Depleted ground water Depleted ground water
Video: Gastroesophageal Reflux Disease (GERD)

For a complete list of videos, visit our video library