This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: About 540 million years ago, a sudden increase in biological complexity occurred, known as the ... (Read 99 times)

aabwk4

  • Hero Member
  • *****
  • Posts: 593
on: Jul 27, 2018
About 540 million years ago, a sudden increase in biological complexity occurred, known as the _______________.
 
  Fill in the blank(s) with correct word

Question 2

As Earth evolved with life, an oxygen abundance of only 0.1 percent would have created a(n) _______________, protecting organisms from the Sun's ultraviolet radiation.
 
  Fill in the blank(s) with correct word


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Mollythedog

  • Sr. Member
  • ****
  • Posts: 340
Reply #1 on: Jul 27, 2018
Answer to Question 1

Cambrian explosion

Answer to Question 2

ozone layer
ozone screen


aabwk4

  • Member
  • Posts: 593
Reply 2 on: Jul 27, 2018
Thanks for the timely response, appreciate it

parker125

  • Member
  • Posts: 332
Reply 3 on: Yesterday
Gracias!

« previous next »
 

Did you know?

According to research, pregnant women tend to eat more if carrying a baby boy. Male fetuses may secrete a chemical that stimulates their mothers to step up her energy intake.

Did you know?

Certain rare plants containing cyanide include apricot pits and a type of potato called cassava. Fortunately, only chronic or massive ingestion of any of these plants can lead to serious poisoning.

Did you know?

Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.

Did you know?

Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.

Did you know?

Less than one of every three adults with high LDL cholesterol has the condition under control. Only 48.1% with the condition are being treated for it.

The cranium of early African H. erectus KNM-ER 3733 is nearly 1.8 million years old. The cranium of early African H. erectus KNM-ER 3733 is nearly 1.8 million years old.
Many diesel fuel additives increase the cetane rating which results in improved fuel economy. Many diesel fuel additives increase the cetane rating which results in improved fuel economy.
Case of ONJ that occurred spontaneously. Note the white area, which is exposed necrotic bone. Case of ONJ that occurred spontaneously. Note the white area, which is exposed necrotic bone.
Effect of an Increase in gA,2 on Productivity and Output Effect of an Increase in gA,2 on Productivity and Output
Trends in employed mothers with a child/children younger than 3 years of age Trends in employed mothers with a child/children younger than 3 years of age
Siri plans to retire in 18 years and would like to receive $10 000.00 per month for twenty ... Siri plans to retire in 18 years and would like to receive $10 000.00 per month for twenty ...
Video: Ultrasound of a Fetus (Sonogram)

For a complete list of videos, visit our video library