Bio 1_LC_Carbohydrates and Lipids (1) PDF

ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No....

ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER TOPIC 1 LEARNING CONTENT BIOMOLECULES: CARBOHYDRATES AND LIPIDS Biological Molecules The major categories of Biological molecules are: Carbohydrates Proteins Lipids (Fats) Nucleic Acids (This will only cover Carbohydrates and Lipids) All of these molecules exist primarily as organic polymers in living things. A polymer is a molecule that is made up of small repeating units called monomers. Polymer Monomer Carbohydrate Monosaccharide Protein Amino acid Nucleic Acid Nucleotide Each of the above categories has different monomers however they all join together the same way through a condensation synthesis reaction. Furthermore, all the polymers listed above can break down into their monomers through a hydrolysis reaction. A. Carbohydrates Functions for quick and short-term energy storage in all organisms. have structural function in plants, bacteria and insects. have a cell recognition role – the ‘glycoprotein’ cell markers on the outside of the membrane are referred to as the glycocalyx. These markers are individualized and this is the mechanism by which donor organs are rejected by recipients. These are the basis for the A, B, O blood groups The glycocalyx also helps cells adhere to each other.  ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER Structure All carbohydrates have approximately 2 hydrogen atoms and 1 oxygen atom (ie. water) for each carbon atom hence the name ‘hydrates of carbon’. Usually, the formula for carbohydrates is given as the molecular formula which gives clues about the structure of the molecule, however the empirical formula of a carbohydrate is sometimes used. ex: glucose molecular formula is C6H12O6, whereas the empirical formula is CH2O. Although easier to write, it happens to have the same empirical formula as formaldehyde and can be therefore confusing. There exist two categories of carbohydrates: Simple and Complex Simple carbohydrates include the monosaccharides and the disaccharides. A monosaccharide is a 3 to 7 carbon chain or ring. A disaccharide is when two monosaccharides are joined through a condensation synthesis reaction. Monosaccharides Disaccharides glucose maltose (glucose + glucose) fructose sucrose (glucose + fructose) galactose lactose ( glucose + galactose) Complex carbohydrates (Polysaccharides) are polymers and are made up of many monosaccharides joined together. Starch, glycogen and cellulose are three examples.  ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER Starch is a storage form of glucose in plants. Up to 4 000 glucose units per starch molecule. There is some side branching, so these 4000 are not all in a single line. Ingested starch gets broken down to glucose by digestive enzymes (both salivary and pancreatic amylase and maltase) and then the body stores it as Glycogen. Glycogen is a storage form of glucose in animals. Considerably more side branching than starch molecules. Glycogen storage is largely in the liver, and the liver slowly releases hydrolyzed glycogen (glucose) into the bloodstream between meals to maintain 0.1% glucose concentration.  ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER Cellulose is a structural polysaccharide used in plant cell walls. Cellulose is also long chains of glucose monomers, but every second bond joining monomers is upside down. This alternation makes this molecule indigestible and is commonly referred to as fiber. Carbohydrates provide body with energy! What should you eat the night before playing the big game? Candy bar or pasta? Candy bar: contains simple sugars, provides a short burst of energy Pasta: contains starch which takes longer to break down, provides longer- lasting energy *We can’t digest cellulose- it is used as fiber, or roughage instead. (Called insoluble fiber in food products) Ex. : corn Carbohydrates: Source of Foods Simple carbs (simple sugars) are found in most candy and sweet drinks, fruit, vegetables, and milk. They are quickly digested and give a short burst of energy.  ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER Complex carbs (like starches) are found in pasta, bread, potatoes, legumes & corn. They take longer to digest and provide energy longer. How many Carbohydrates do you need? The Dietary Guidelines for Americans recommend that carbohydrates make up 45% to 65% of total daily calories. So if you get 2,000 calories a day, between 900 and 1,300 calories should be from carbohydrates. That translates to between 225 and 325 grams of carbs a day. You can find the carbohydrate content of packaged foods on the Nutrition Facts label. The label shows total carbohydrates — which can include fiber, total sugars and added sugars. B. Lipids (Fats and Oils, Phospholipids, and Steroids) Functions Fats function as energy storage molecules, insulators against heat loss, and cushion tissue for organs. Oils are generally something in our diet, however they are converted to fats in our bodies and therefore only function as a nutrient. Phospholipids are the main component of membranes. Steroids generally act as hormones (messenger molecules) and are also components of cell membranes (cholesterol) Structure All lipids are insoluble in water on their own. Emulsifiers allow lipids to mix into water. An emulsifier has a nonpolar end that points towards the fat/oil and a polar end that allows it to be dissolved into water. Bile contains emulsifiers.  ATENEO DE DAV AO UNIVERSITY Km 7 Central Park Blvd, Talomo, 8016 Davao City, Philippines Tel No. +63 (82) 221.2411 local 8608 E-Mail: [email protected] * www.addu.edu.ph In Consortium with Ateneo de Zamboanga University and Xavier University SENIOR HIGH SCHOOL – BIOLOGY AND EARTH & LIFE SCIENCE CLUSTER Fats and oils OR triglycerides OR neutral fats All formed from one glycerol molecule reacted with three fatty acid molecules through a condensation synthesis reaction. Fatty acids come in two varieties: Saturated: the carbon chain is completely surrounded by hydrogen; only single covalent bonds between the carbons. Solid at room temp. Unsaturated: the carbon chain is partially surrounded by hydrogen because of some double bonds between the carbon atoms. Liquid at room temp. Often they are hydrogenated in foods. Philippines starts ban on trans fat in prepackaged processed food products: This policy is meant to address the high consumption of trans fat, which increases the risk of developing coronary heart disease and other diseases. The Food and Drug Administration (FDA) is taking steps in eliminating trans-fat in the American diet. Adding Hydrogen Partially hydrogenated oils are the primary dietary source of artificial trans-fat in processed food. Phospholipids These are similar to the triglycerides except there are only 2 fatty acids. Instead of a third, there is a phosphate/nitrogen group. The phosphate/Nitrogen group is charged and phospholipids therefore have non-polar hydrophobic regions (fatty acids and the glycerol) and polar hydrophilic regions (the phosphate/nitrogen group). Steroids Basic structure is 4 fused carbon rings with various functional groups around the outside. Cholesterol is the classic steroid and is the precursor for many other hormones in the body (ex. Testosterone, and estrogen). Cholesterol is a component of cell membranes.