Conduction, convection, and radiation
Brain energy requirement, metabolism and neurotransmitter turnover consume 20 % of the available oxygen and glucose in the body.
<span>Even though, the brain is only about 2% of the body weight, it consumes about 20% of the body's energy. It is the main consumer of glucose-derived energy. When the mental strain increases, the brain's demand for energy in the form of oxygen and glucose is higher.</span>
The carbon cycle is one of earths natural resources that enables all living organisms to inhabit the planet. For example, with out this vital resource we would run out of oxygen. Flora (plants and trees) use the carbon that is a by product of cellular respiration by fauna (humans and animals) to reproduce oxygen and this cycle continues. which is what keeps all living organisms in harmony and alive.