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 three systems in our body that work together are cardiovascular, respiratory and digestive systems which supply energy to the cells of the body. I will be describing their role of energy in the body system also I am going to explain the physiology of the three named body systems in relation to energy metabolism.he respiratory allows the digestive tract to function and same for the digestive system. Also they both work together to provide energy to body cell. The metabolism is tied to the respiratory system because the system is responsible for providing oxygen in oneâs body. Digestive System.