Lipids are used by organisms for energy storage, as a signalling molecule (e.g., steroid hormones), and as a structural component of cell membranes. Although there is no single common structure for lipids, the most commonly occurring class of lipids are triglycerides, which are fats and oils.ipid Structure. The second most abundant class of lipids are the phospholipids, which are found in animal and plant cell membranes. Phospholipids also contain glycerol and fatty acids, plus the contain phosphoric acid and a low-molecular-weight alcohol.
As soon as this was over, Plataea was besieged by a combined force of Sparta and Thebes. In 431 B.C. when the corn was ripe, King Archidamus with a large Peloponnesian army invaded Attica, in an effort to destroy the Athenian countryside. This he did, causing the country people to flee to the city of Athens.
Kimon was exiled by an angry public, and the alliance between Sparta and Athens crumbled. Two years later the First Peloponnesian War (460-446) began. This was not really a single fifteen year long struggle, but was a series of clashes between Athens, Sparta and their allies.