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 heart is the most important muscle of the body because it is the organ that pumps the blood throughout the body to carry out oxygen and nutrients, and helps collect and el â¦ iminate carbon dioxide and other wastes from the body.1 person found this useful.ell I really believe the most important muscle in your body is your heart since it is vital to your existence. It helps oxygenated blood pump out to all your muscle and other body organs and the brain to help with All your body's movement and activities of day to day living. 2 people found this useful. 4 Jays.