A copy of the DNA is made just prior to when a cell is going to split to create two cells. In order for this replication of DNA to take place, the DNA has to be in an orientation that will allow the replication machinery to make a copy. Our DNA is double-stranded, with the strands being held together by hydrogen bonds. The normal structure of our DNA when it is not being copied is a double helix. This looks very similar to a winding staircase.

In this normal form, the DNA cannot be copied. DNA helicase is needed in order to open the DNA to expose the nucleotide bases that are used as the template for replicating the DNA. The area of the DNA that is opened by DNA helicase is known as the replication fork because it looks very similar to a fork in the road.

Our body needs glucose, which comes from carbohydrates, to survive. The brain can only use energy that has come from glucose, yet the body can only store enough glucose to last for less than two hours. So what happens if you only eat meat for a day? What does the body do to prevent us from dying? The body has a pathway called gluconeogenesis, which creates glucose from other molecules. This is the pathway that prevents us from dying when we haven't had any bread, vegetables, or other carbohydrates for a few hours.

The metabolic pathway, gluconeogenesis, is the synthesis of glucose from three- and four-carbon molecules, such as pyruvate. These molecules can be synthesized from some amino acids and triglycerides. The body will also use gluconeogenesis if too much of the glucose has been converted into pyruvate through glycolysis. The process can be reversed and turn the pyruvate back into glucose for storage or usage elsewhere in the body.