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>
<span>Adrenaline can change many things including increasing blood pressure, heart rate, reflexes, physical and psychological capabilities, and many more. When under stress, adrenaline is released to help the body defend itself from that stress. That's why when children are drowning, for example, those saving them must be extremely careful because a child can due to adrenaline become even stronger than an adult and can accidentaly drown the adult.</span>
It’s the letter C.................
They construct dams and create an ecosystem for other species . Because of their dam building nests become available for birds, fish population increases and waterfowl population goes up