Spread spectrum. In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth.
Lipids are one of the four major groups of organic molecules; the other three being proteins, nucleic acids (DNA), and carbohydrates (sugars). Lipids are made up of the same elements as carbohydrates: carbon, hydrogen, and oxygen.
The structure of a cell membrane is made up of proteins and phospholipids. Phospholipids are organic compounds made out of fats, or oils. These materials make up the majority of the membrane's surface. Proteins reside within the crevices built into the membrane.