Is a double helix with paired bases, adenine and thymine, and guanine and cytosine.

a.
trna
c.
rrna
b.
mrna
d.
dna

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?

Which term describes a normal value for something in the body? a.homeostasis b.set point c.feedback loop d.integration center

Which of these is an example of land degradation? a. containers designed to store pollutants leak. b. fertilizers provide too many nutrients to crops. c. garbage is buried so the land can be reclaimed later. d. a drought kills all the plants in an area, leaving bare land