« previous next »

Author Question: Earth's first atmosphere was rich in water vapor but poor in free oxygen. The atmosphere became more ... (Read 125 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?

Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.

Did you know?

There are more bacteria in your mouth than there are people in the world.

Did you know?

Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.

Did you know?

Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%

Did you know?

Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.

Annual net primary productivity on Earth. Annual net primary productivity on Earth.
To travel quickly, killer whales leap out of the water when swimming—a behaviour kn To travel quickly, killer whales leap out of the water when swimming—a behaviour kn
Surface Water Resources Surface Water Resources
All brakes should be moistened with water or solvent to help prevent brake dust from becoming ... All brakes should be moistened with water or solvent to help prevent brake dust from becoming ...
The Role of Gases in the Atmosphere The Role of Gases in the Atmosphere
Percent of oxygen in the atmosphere versus altitude. Percent of oxygen in the atmosphere versus altitude.
Video: Burn Animation

For a complete list of videos, visit our video library