Lipids PDF

LIPIDS - an oily organic compound insoluble in water but soluble in organic solvents. - A group of compounds responsible for energy storage, structure of the cell membrane, coordinating physiological processes, waterproofing, insulation and protection in our body. Structure of L...

LIPIDS - an oily organic compound insoluble in water but soluble in organic solvents. - A group of compounds responsible for energy storage, structure of the cell membrane, coordinating physiological processes, waterproofing, insulation and protection in our body. Structure of Lipids Glycerol Backbone - three-carbon alcohol molecule Saturated and unsaturated fatty acids - Hydrocarbon chains with a Carboxyl group(-COOH) at the and Phosphate groups, sugars and others - additional groups exclusive to more complex lipids. CLASSIFICATION OF LIPIDS 1. Simple Lipids - composed of long chain fatty acids - may either be free or combined with an alcohol by an ester linkage - ex. Fats(Triglycerides ) - primary storage form of energy in animals including humans. - composed of glycerol and three fatty acids Waxes - found in animal coatings and plant cuticles. - bonded to long-chain alcohols, primarily used for water repellency 2. Complex Lipids Phospholipids - Contain a glycerol backbone, two fatty acids, and a phosphate group. They are a major component of cell membranes, forming the lipid bilayer. Glycolipids- Composed of a carbohydrate attached to a lipid, they play roles in cell recognition and signaling. 3. Derived Lipids Steroids - these include cholesterol, which is crucial for membrane fluidity and steroids hormones like Cortisol, testosterone and estrogen. Terpenes - A large diverse class of organic compounds produced by plants, contributing to the formation of Vitamins (like Vitamin A) and pigments. Example of Lipids Triglycerides - found in animal fat and vegetable oil.  Phospholipids - Found in cell membranes such as phosphatidylcholine. Cholesterol - found in animal cell membrane and serves as a precursor for steroid hormones. Steroids hormones - include testosterone, estrogen and cortisol. Waxes - found in beeswax, earwax and the cuticle of plants. LIPIDS ROLE IN METABOLIC PROCESSES 1. Lipids, particularly triglycerides, serve as a major energy reserve. When carbohydrates are scarce, the body breaks down these fats for energy. 2. Phospholipids and cholesterol are integral to cell membranes, providing structure and fluidity essential for cell function. 3. Certain lipids, such as steroid hormones and eicosanoids, act as signaling molecules that regulate various physiological processes, including inflammation, metabolism, and immune responses. 4. Lipids provide insulation for body organs and help protect them from physical shock. 5. Lipids facilitate the absorption of fat-soluble vitamins (A, D, E, and K) and other essential nutrients.