Because energy is being consumed. It takes energy to lift things, walk around, etc. We are transferring our chemical energy from meals to our environment and basic functions. The answer to the second part is probably that so much energy has been transferred and stored in our surroundings, and it's difficult to gather that energy into a useful medium for us to use again.
The leaves of carrots contain chlorophyll which gives them their green color.
Stored in the carrot roots is extra glucose that serves as a food source for the second year's growth of the carrot plant. The carrot plant needs this stored eneergy to reproduce in its second year.
Although the core and mantle are about equal in thickness, the core actually forms only 15 percent of the Earth's volume, whereas the mantle occupies 84 percent. The crust makes up the remaining 1 percent.
It states that total amount of energy in a system remains constant in isolated system. This means energy can neither be created nor it can be destroyed but can change from one form to another.
Energy can change from kinetic to potential energy, and back without reducing the total energy.
