A plough (UK) or plow (US; both /ËplaÊ/) is a tool or farm implement used in farming for initial cultivation of soil in preparation for sowing seed or planting to loosen or turn the soil. Ploughs were traditionally drawn by working animals such as horses or cattle, but in modern times are drawn by tractors.
Polar/Nonpolar Regions. In a biological membrane, the phospholipids are organized into a bilayer, which serves as the framework in which the other components of the membrane are embedded.
The Bilayer. The phospholipids organize themselves in a bilayer to hide their hydrophobic tail regions and expose the hydrophilic regions to water. This organization is spontaneous, meaning it is a natural process and does not require energy.This structure forms the layer that is the wall between the inside and outside of the cell.ince a lipid molecule contains regions that are both polar and nonpolar, they are called amphipathic molecules. Figure %: Basic Lipid Structure. The most abundant class of lipid molecule found in cell membranes is the phospholipid.