1 An unopened container should last for 1-3 months at 40Â°F or less in the refrigerator, but some companies guarantee their product for up to 6 months.  If left in its partially-open original paper wrap, the exposed area of stick butter will begin to harden and smell stale after about a week, as oxygen sets in.
Quick Answer. Humans need a respiratory system because it is made up of organs that allow them to breathe. Breathing delivers oxygen to the body and takes away carbon dioxide. Every cell in the body needs oxygen to obtain energy from food. Continue Reading.
The respiratory system is the group of tissues and organs in your body that enable you to breathe. This system includes your airways, your lungs and the blood vessels and muscles attached to them that work together so you can breathe.The respiratory system's primary function is to supply oxygen to all the parts of your body.It accomplishes this through breathing: inhaling oxygen-rich air and exhaling air filled with carbon dioxide, which is a waste gas.he respiratory system is made up of airways (your nose, mouth, voice box, windpipe and bronchial tubes) and the lungs and the muscles and blood vessels connected to them.