Question: What Are the Elements in the Human Body? Answer: Most of the human body is made up of water, H2O, with cells consisting of 65-90% water by weight. Therefore, it isn't surprising that most of a human body's mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. You may also wish to view the element composition of an average human body by mass.
1 The freezer time shown is for best quality only â foods kept constantly frozen at 0Â° F will keep safe indefinitely.  How long does cooked steak last at room temperature? Bacteria grow rapidly at temperatures between 40 Â°F and 140 Â°F; cooked steak should be discarded if left for more than 2 hours at room temperature.
1 How long does ground beef last in the fridge once it is cooked? 2  Cooked ground beef will usually stay good for 3 to 4 days in the fridge and 3 months in the freezer. Ground beef that has been defrosted in the fridge can be kept for an additional 1 to 2 days in the refrigerator before cooking; ground beef that was thawed in the microwave or in cold water should be cooked immediately.