Question 2 of 10 How many hydrogen atoms are present in each water molecule?
A. 2.
B. 4
C. 3
D. 1

The first amino acid of a new polypeptide chain is

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

How does the human body lever work?