DNA structure. DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).The order of these bases is what determines DNA's instructions, or genetic code.NA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code.
A beef roast cooked to medium-rare should have an internal temperature of 145Â°F - 150ÂºF after the resting period, and a roast cooked to medium should have an internal temperature of 150Â°F to 160ÂºF. (See the note below). See Beef Doneness for more information on proper cooking temperatures. Cook the roast for about 10 to 15 minutes and then turn it over in the pan. 2  Continue to cook it for another 10 to 15 minutes for every pound. 3  Remove the tenderloin from the oven when the internal temperature of the meat reaches 140Â°F, as indicated on a meat thermometer inserted into the center of the roast.
Check the internal temperature of the roast as it nears its completion time. Beef, lamb or pork should register between 125 and 130 degrees Fahrenheit for rare, between 130 and 140 degrees for medium rare and about 140 to 145 degrees for medium.Cook poultry to an internal temperature of about 165 degrees Fahrenheit.Depending on how you want the roast done, increase the oven's temperature to 500 degrees about 15 minutes before it reaches its final temperature. Roast it at the higher temperature for another 10 minutes for a browned and crunchier crust.se a Dutch oven or a roasting pan. The key is to allow the meat to cook gradually. Slow cooking is more appropriate for beef, pork and lamb than it is for boneless poultry, though thighs and leg pieces work well with this method.