In adults, eczema occurs most frequently on the hands and elbows, and in bending areas such as the inside of the elbows and back of the knees. In young children, eczema is often seen on the elbows, knees, face, neck, and scalp. Signs and symptoms of atopic eczema include: 1  Itchiness. 2  Skin redness.
Sphingolipids are composed of a backbone of sphingosine which is derived itself from glycerol. Sphingosine is N-acetylated by a variety of fatty acids generating a family of molecules referred to as ceramides. Sphingolipids predominate in the myelin sheath of nerve fibers.
Structure. Phospholipids are composed of two fatty acid tails attached to a glycerol head, according to Biology: Concepts and Connections.. The glycerol attaches to a phosphate group. The head is hydrophillic, meaning it's attracted to water.The tail is hydrophobic, or resistant to water.hospholipids are composed of two fatty acid tails attached to a glycerol head, according to Biology: Concepts and Connections.. The glycerol attaches to a phosphate group. The head is hydrophillic, meaning it's attracted to water. The tail is hydrophobic, or resistant to water.