What percentage of the species that have ever lived have become extinct?

a. 1 percent
b. 9 percent
c. 50 percent
d. 75 percent
e. 99 percent


E

Biology & Microbiology

You might also like to view...

Geneticists can create sequences of DNA from RNA using enzymes called ________.

A. palindromes B. reverse transcriptases C. restriction endonucleases D. ligases E. DNA polymerases

Biology & Microbiology

A(n) ________ is a group of three bases on tRNA that is complementary to a specific mRNA codon.

A. poly-A tail B. anticodon C. codon D. cap

Biology & Microbiology

The thickness of a questioned glass sample can be measured with a _____.

What will be an ideal response?

Biology & Microbiology

The study of the immune system is known as:

Fill in the blank(s) with the appropriate word(s)

Biology & Microbiology