<span>A depressant must reduce mental activity and decrease physical activity. A depressant acts by interfering with and reducing the levels of activity in neuro-transmitters. This serves to slow down the chemical processes within the brain which consequently lowers the level of mental activity or arousal. The brain also programs the body to reduce the levels of physical activity in a proportionate manner.</span>
Answer: A large amount of energy is lost at each level, so there has to be a limit on the number of trophic levels.
Explanation:
Constitutional monarchy I’m sure it’s that.
