Lipid functions

1. ANIMAL BIOCHEMISTRY Presented by: Hina Amir Functions of Lipids

2. FUNCTIONS OF LIPIDS ENERGY INDUSTRY IMMUNITY SIGNALING VITAMIN MEMBRANES LIPIDS

3. Lipids form excellent energy storage molecules As lipid deposits in stroma of the chloroplast Carry 9 kilocalories of energy as opposed to 4 kilocalories that carbohydrates Waxes stored in plan kton as biofuel Adipose tissue of vertebrates . Fats in seeds Energy storage

4. Lipids or Glucose for Energy? More reduced state (more H bound to C)  More potential for oxidation Less reduced state (more O bound to C)  Less potential for oxidation

5. 2. Thermal insulation Fat conducts heat slowly and therefore the triglycerides, which are stored as fat in vertebrates, are important for maintaining optimum temperature. It help in conserving energy of organisms undergoing hibernation.

6. Mechanical protection Adipose tissue act as physical cushion in the palms of the hands , soles of the feet, and around the eyes kidneys . Waterproofing The waxy cuticle on the leaf epidermis or as oils on birds’ feathers.

7. Buoyancy Since fat is less dense than water, fat reserves provide buoyancy for aquatic animals.

8. In the liver cholesterol is the precursor of the bile acids, 24 steroid carboxylic acids that aid in the digestion of foods, especially lipids, and, when linked with the amino acids glycine or taurine , form the bile salts As digestive enzyme

9. Platelet-activating factor (PAF) is a potent mediator that occurs at very low concentrations in cells and tissues Immune response

10. Dipalmitoyl lecithin:surfactant . Absence of it causes respiratory distress. As surfactant

11. Phosphatidylethanolamine in addition to phosphatidylserine ( found in most tissues) are also found in cell membranes. Phosphatidylserine also plays a role in apoptosis (programmed cell death). Apoptosis

12. While studying sleep inducing substances researchers point out that certain lipids or lipids derivatives are involved in sleep induction ; Prostaglandin in rodents, primates, and most probably in humans as well Sleep Induction

13. Liposomes when combined with tissue-specific antibodies function as carriers of drugs in the circulation, targeted to specific organs, e.g. in cancer therapy . Plant-derived isoprenoid compounds include rubber, camphor (used in several cough preparations) : Isoprene unit. Medicine

14. Arachidonic acid is the eicosanoid precursor Eicosanoids are three groups of structurally related compounds Prostaglandins Leukotrienes Thromboxanes Biological functions:

15. Biological Processes Regulated by Eicosanoids Blood clotting(prostaglandin) dilates blood vessels inhibits platelet aggregation Inflammatory response

16. Lipid rafts are plasma membrane microdomains rich in cholesterol and sphingolipids . important for neuronal cell adhesion, axon guidance and synaptic transmission. crucial for neural development and function. Neural functioning

17. Insect cuticle waterproof and prevent from desication Stress Tolerance in Cyanobacteria I n plants the leaves are covered by waxy cuticles, which prevent excess water loss or entry . Carnuba, from Brasilian wax palm In animals, such as ducks, oil is found on their feathers to ensure excess water is not absorbed. In vertebrates , a waxy layer is found on their skin and fur. Some bees are able to synthesise their own wax, which is used to construct a honeycomb . Beeswax Structural support

18. Lauric acid is a medium chain fatty acid antiviral, antibacterial, and antiprotozoal. destroy lipid-coated viruses such as HIV, herpes, influenza, pathogenic bacteria. Coconut oil. Function as antibacterial

19. Cholesterol is vital in producing vitamin D and some hormones Gibberellins – plant growth substances e.g. carotenes, photosynthetic pigments, coloration pigments, steroid hormone. Precursor

20. While plant oils such as cotton, coconut, palm, castor beans, soy, and sunflowers are also natural sources of stearic acid, Soap making. deodorants foundation creams, hand lotions, hair straightening products, and shaving creams . Cosmetic industry Fatty acids are the main component of soap, where their tails are soluble in oily dirt and their heads are soluble in water to emulsify and wash away the oily dirt.

21. Numerous plant oils, or lipids, go into making natural insecticides. Catnip oil repels mosquitoes by irritating them, canola oil controls a variety of insects. Citronella oil is used in candles, lotions, sprays and wipes to repel insects. Citrus oils, pine oil and mint oil also are used to produce insecticides. In pesticides

22. Biodiesel is a clean-burning fuel produced from plant lipids such as soybean oil and will be a good source of feul in near future. Lubricants palm, sunflower, soybean oils are used to make industrial bio-lubricants. engine oil, grease and metalworking fluids. Fuel + lubricant

23. CONCLUSION