The DNA bases are adenine, guanine, thymine, and cytosine. In RNA, Thymine is replaced by Uracil.nswer by Pieman3113. Confidence votes 4. The DNA bases are adenine, guanine, thymine, and cytosine. In RNA, Thymine is replaced by Uracil. Adenine and guanine are known as purines and cytosine and thymine are known as pyrimidines.
Airmail is a mail transport service branded and sold on the basis of at least one leg of its journey being by air. Airmail items typically arrive more quickly than surface mail, and usually cost more to send. Airmail may be the only option for sending mail to some destinations, such as overseas, if the mail cannot wait the time it would take to arrive by ship, sometimes weeks. The Universal Postal Union adopted comprehensive rules for airmail at its 1929 Postal Union Congress in London. Since th
Army Air Service pilots flew the route until August 10, 1918, when the Post Office Department took over the entire operation with its own planes and pilots. Attempts to start airmail service had begun as early as 1912, when it seemed that the airplane might develop into a practicable means of transportation.