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.
In contrast, the long isoprene or. fatty-acid tails of a phospholipid are nonpolar. Water mole-. cules cannot form hydrogen bonds with the hydrocarbon tail, so they do not interact with this part of the molecule. Compounds that contain both hydrophilic and hydrophobic. elements are amphipathic (âdual-sympathyâ).