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.
The Peloponnesian War had a lasting effect on the Greek world. Both Sparta and Athens were weakend. Thebes, defeated Sparta at the Battle of Leuctra in 371 BC to become the most powerful Greek polis, and then, Philip II of Macedonia defeated Thebes and the Greek allies to become master of the Greek world.