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 also works closely with all other systems of the body. The respiratory system provides oxygen for all body parts. It also removes carbon dioxide from the muscular, digestive, skeletal, circulatory, urinary and nervous systems. This system includes the nose, larynx, trachea and the lungs.irculatory System. The circulatory system helps move oxygen through the body created by the respiratory system. This system also has the task of moving wastes that need to be disposed of. This system includes the heart, veins, arteries, capillaries and blood.