Lipids 1-2 Flashcards
Define the major lipid classes and their role in health and disease.
Fatty acids - essential for normal growth and development and may play an important role in the prevention and treatment of coronary artery disease, hypertension, diabetes, arthritis, other inflammatory and autoimmune disorders, and cancer. Can also cause worsened symptoms of ADHD, dermatitis and alopecia.
Triacylglycerol - When your body needs energy, it releases the triglycerides. Some triglycerides are important for good health. However, high triglyceride levels in your blood can raise your risk of heart disease and stroke. High blood triglycerides are a type of lipid disorder.
Phospholipid - Imbalances has been implicated with many neurological disorders , including bipolar disorders, schizophrenia, and neurodegenerative diseases such as Alzheimer’s, Parkinson’s, Niemann-Pick and Huntington diseases.
Glycolipid - Glycolipids are lipids with a carbohydrate attached by a glycosidic (covalent) bond. Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connections that allow cells to connect to one another to form tissues.
Steroids - Work by decreasing inflammation and reducing the activity of the immune system. Inflammation is a process in which the body’s white blood cells and chemicals can protect against infection and foreign substances such as bacteria and viruses.
Describe the structure and functions of cholesterol.
Cholesterol is a 27 carbon compound with a unique structure with a hydrocarbon tail, a central sterol nucleus made of four hydrocarbon rings, and a hydroxyl group. The center sterol nucleus or ring is a feature of all steroid hormones.
Describe the structure and functions of eicosanoids and steroid lipids.
Steroids are hormones that keep the cell membrane from becoming excessively fluid. Cholesterol is one of them (adds structure). Eicosanoids play a role in the generation of pain and fever and blood pressure, blood coagulation, and reproduction.
Describe in outline the processes of lipid digestion and absorption.
Crude emulsions of lipids enter the duodenum as fine lipid droplets and then mix with bile and pancreatic juice to undergo marked changes in chemical and physical form. Emulsification continues in the duodenum along with hydrolysis and micellization in preparation for absorption across the intestinal wall.
Describe how lipids are transported in the body and the role of lipoproteins in this
process.
Lipoproteins play a key role in the absorption and transport of dietary lipids by the small intestine, in the transport of lipids from the liver to peripheral tissues, and the transport of lipids from peripheral tissues to the liver and intestine (reverse cholesterol transport).
Describe the synthesis of free fatty acids and define the term ‘essential fatty acid’.
The term essential fatty acids (EFA) refers to those polyunsaturated fatty acids (PUFA) that must be provided by foods because these cannot be synthesized in the body yet are necessary for health.
In biochemistry, fatty acid synthesis is the creation of fatty acids from acetyl-CoA and NADPH through the action of enzymes called fatty acid synthases. This process takes place in the cytoplasm of the cell.
Describe the catabolism of fatty acids by beta-oxidation.
In biochemistry and metabolism, beta oxidation (also β-oxidation) is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA.
Describe the function, synthesis and metabolism of ketone bodies.
Ketone bodies have an important role as an energy source during starvation. In the liver, fatty acyl CoA is converted into ketone bodies (3-hydroxybutyrate [βOHB] and acetoacetate [AcAc]). The ketone bodies are efficiently metabolized in peripheral tissues except in the brain.
