Answer the following question given this paragraph: 

Starvation When the body is deprived of nourishment for an extended period of time, it goes into “survival mode. ” The first priority for survival is to provide enough glucose or fuel for the brain. The second priority is the conservation of amino acids for proteins. Therefore, the body uses ketones to satisfy the energy needs of the brain and other glucose-dependent organs, and to maintain proteins in the cells (see Figure 24.2). Because glucose levels are very low during starvation, glycolysis will shut off in cells that can use alternative fuels. For example, muscles will switch from using glucose to fatty acids as fuel.


Q: When the body goes into survival mode, it's first priority is to produce enough of which substance for the brain?


A:
glucose