Problem: Oxygen concentration of 1% of 1 billion years ago increased to the present level of 21% because of photosynthetic activity ofa. fungib. cyanobacteriac. plantsd. protistse. animals

FREE Expert Solution
Problem Details

Oxygen concentration of 1% of 1 billion years ago increased to the present level of 21% because of photosynthetic activity of

a. fungi

b. cyanobacteria

c. plants

d. protists

e. animals