Lipid Bilayer.A plasma membrane is made up of Lipid Bilayers, which consists of polar phosphate heads, which are hydrophilic or water loving, and non-polar fatty acid tails, which are hydrophobic. Proteins are embedded in the membrane as well.Cell membranes are known to have holes, or selective permeable.
A water molecule (H2O) will have a slightly positive side, and a slightly negative side. The oxygen side of water is the one that is negative, while hydrogen side tends to be more positive. When a molecule has a half negative and half positive side like water does, it is called a polar molecule. :D
1- the reactions that cause milk to spoil are slower at lower temperatures.
This is a combustion reaction because products of the reaction include carbon dioxide and water.