Composite volcanoes. Had this question on apex:)
It differs from DNA chemically in two respects: (1) the nucleotides in RNAare ribonucleotides—that is, they contain the sugar ribose (hence the name ribonucleic acid) rather than deoxyribose; (2) although, like DNA,RNA contains the bases adenine (A), guanine (G), and cytosine (C), it contains the base uracil (U) .
The outer core. A molten nickle- iron alloy.
As food reaches the end of the esophagus, it enters the stomach through a muscular valve called the lower esophageal sphincter. The stomach secretes acid and enzymes that digest food. Ridges of muscle tissue called rugae line the stomach. The stomach muscles contract periodically, churning food to enhance digestion.Mar 4, 2016
