Legal drinking age. The legal drinking age is the age at which a person can legally consume or purchase alcoholic beverages. These laws cover a wide range of issues and behaviors, addressing when and where alcohol can be consumed.
An open system is a system that has external interactions. Such interactions can take the form of information, energy, or material transfers into or out of the system boundary, depending on the discipline which defines the concept.
An open circulatory system describes a system where blood and interstitial fluid are allowed to mix in an organism. Interstitial fluid is just the fluid found between cells in the body.nother interesting aspect about organisms that utilize an open circulatory system is they can't create a blood pressure. In mammals, our blood pressure is due to the pumping of our heart. Remember, our blood is separated from our interstitial fluid.