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Chemical Energy

Chemical Energy. Review of basic chemistry. Element – any substance that cannot be broken down into a simpler substance Ex – carbon, nitrogen, oxygen, hydrogen Atom – smallest unit of an element Compound – two or more elements chemically combined Ex – water, sugar, starch

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Chemical Energy

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  1. Chemical Energy

  2. Review of basic chemistry • Element – any substance that cannot be broken down into a simpler substance • Ex – carbon, nitrogen, oxygen, hydrogen • Atom– smallest unit of an element • Compound – two or more elements chemically combined • Ex – water, sugar, starch • Molecule – smallest unit of most compounds • Ex – H2O, C6H12O6, O2, CO2

  3. Inorganic Compounds • Don’t contain Carbon, Hydrogen, and Oxygen • Ex – water (H2O), salt (Sodium chloride), CO2

  4. Organic Compounds • Contain Carbon, Hydrogen and Oxygen • Includes: Carbohydrates Proteins Lipids Nucleic Acids

  5. Proteins • Contain C, H, O, N and sometimes Sulfur • Found in many foods • In the cell, used as: part of cell membranes structures of organelles muscles in the body

  6. Structure of Proteins • Made of amino acids • There are 20 different amino acids in living things • These aa’s link together to form a large molecule of 50-3000 aa’s in one protein. • Change one aa, changes whole protein

  7. Protein

  8. Enzymes • Special kinds of proteins • Chemicals that speed up chemical reactions in the body without being used up themselves. • Here the enzyme helps break a large molecule into 2 smaller ones. Some enzymes join two small molecules to make one larger one.

  9. Enzymes • Special kinds of proteins • Chemicals that speed up chemical reactions in the body without being used up themselves. • Here the enzyme helps break a large molecule into 2 smaller ones. Some enzymes join two small molecules to make one larger one.

  10. Carbohydrates • Energy rich • C, H, and O • Simple sugars - glucose • Complex carbohydrates – made up of many simple sugars attached to each other • Starch • Cellulose – make up plant cell walls Found in cell membranes, other cell parts, and store energy

  11. Lipids • Fats, oils, waxes • Store energy • Made of C, H, and O • Contain more energy than carbs

  12. Nucleic Acids • DNA = deoxyribonucleic acid • RNA – ribonucleic acid • Made of C, H, O, N, and Phosphorus • Contain instructions for cells to carry out all their functions.

  13. Water • Makes up about two thirds of your body. • Most chemical reactions occur in water. • Essential for all life.

  14. Food and Digestion- • Why do we need food? • Material for growth, repair • Energy • Allows body to maintain homeostasis

  15. Nutrients – substances in food that provides body with raw materials and energy to carry out essential processes • Carbohydrates • Fats • Proteins • Vitamins • Minerals • Water

  16. Energy • Carbs, fats and proteins provide body with energy • Amount of energy in food measured in calories • One calorie is the amount of energy to raise the temperature of 1 gram of water 1 degree Celsius

  17. Calorie or calorie? • Calorie – used to measure energy in foods. • 1 Calorie = 1000 calories • Ex – 1 apple contains 50 Calories or 50,000 calories. • The more calories a food has, the more energy it contains.

  18. Amount of Calories needed? • Depends on physical needs and age of the person • Very active people need more • Infants and small children need more • Older people need fewer

  19. Carbohydrates • 1 gram carbohydrates provides 4 Calories of energy • Provide raw materials to make cell parts • Two groups: • Simple carbohydrates • Complex carbohydrates

  20. Simple Carbohydrates = Sugars • Found in fruits, vegetables, milk • Glucose (C6H12O6) – major source of energy for your cells. • Another simple sugar = fructose in fruits

  21. Complex Carbohydrates • Made of many simple sugars connected • Starch – found in potatoes, wheat, rice, corn • Fiber (Cellulose) – found in plants, but cannot be digested and passes through your digestive system - helps keep things moving along.

  22. How much carbohydrates do you need? • 50-60% of Calories should come from carbs. • Complex carbs are better to eat than simple carbs – sugars give a quick burst of energy, but starches are a longer, more even energy source. • Foods high in complex carbs usually have other useful nutrients • Foods with lots of sugar usually have fewer other useful nutrients

  23. FATS • Contain more than 2x the energy of carbohydrates • Store energy • Parts of cells • Protect internal organs • Insulate the body

  24. Types of Fats • Unsaturated Fats • Liquid at room temprerature • Oils • Considered good for you • Saturated Fats • Solid at room temperature • From animals; a few plants – coconut palm • Bad for you

  25. Cholesterol • Saturated fat found in meat, eggs, cheese, etc • Necessary for cell membranes in animals • Not needed in diet; liver makes all that is needed. • Can clog arteries and lead to heart attack

  26. How much fat do we need? • Should have no more than 30% of Calories in diet from fat • Should particularly limit intake of saturated fats and cholesterol • Read labels – look for palm or coconut oil, hydrogenated or partially hydrogenated oils – these are bad for you and you should avoid them if you can

  27. Proteins in the diet • For tissue growth and repair • Enzymes speed up chemical reactions • Can be used for energy, but not usually • About 12% of your daily Calorie intake should be protein

  28. Amino Acids • The body makes about half the amino acids it needs • Remainder come from food • Complete proteins -contain all of the essential amino acids • Meat and eggs • Incomplete proteins – missing one or more essential amino acid • Beans, grains, and nuts

  29. Vitamins • Act as helper molecules for a variety of chemical reactions in the body. • The body makes some – K is made by bacteria in intestine • The rest come from foods – eating a wide variety of foods provides all the vitamins needed.

  30. Types of Vitamins • Fat soluble vitamins • Dissolve in fatty tissue and are stored there. • Excess buildup can be dangerous • Includes vitamins A, D, E and K • Water soluble vitamins • Dissolve in water and not stored in body • Needed in diet every day. • Includes vitamins B and C

  31. Fat-Soluble Vitamins • Vitamin A • Vitamin D • Vitamin E • Vitamin K

  32. Water-Soluble Vitamins • Vitamin B-Complex • Thiamin (vitamin B1) • Riboflavin (vitamin B2) • Niacin (nicotinamide, nicotinic acid) • Vitamin B6 (pyridoxine, pyridoxal, pyridoxamine) • Folacin (folic acid) • Vitamin B12 • Vitamin C

  33. Minerals • Nutrients not made by living things • In soil and absorbed by plants • Body needs 15 minerals for cell function and structure • Includes calcium, phosphorus and iron • Large amounts can be toxic

  34. Minerals • Calcium: A mineral important for strong teeth and bones and for muscle and nerve function. The major mineral constituent of bone. • sources: milk and milk products, fish with bones that are eaten, turnip and mustard greens, tofu, almonds and broccoli. • Chloride: A mineral that regulates body fluid volume, concentration and acid-base balance. Balance intertwined with that of sodium • Chromium: A mineral important in regulating blood glucose. sources: brewer's yeast, whole grains and meats • Copper: A mineral that is important for nerve function, bone maintenance, growth, blood formation and utilization of glucose. • sources: organ meats, sea foods, nuts and seeds

  35. Minerals • Fluoride: A mineral that is important to dental and bone health. Greatly improves resistance to cavities • sources: fluoridated water, foods cooked in or containing fluoridated water, fish with bones that are eaten, and tea • Phosphorus: A mineral essential to bone formation and maintenance, energy metabolism, nerve function and acid balance. • sources: meat, poultry, fish, eggs, dairy products and cereal products. • Potassium: A mineral that is essential for nerve function, muscle contraction and maintenance of normal blood pressure. - sources: fruits and vegetables.

  36. Vitamin and Mineral Deficiencies • Lack of Vitamin D disrupted absorption of calcium as a child.

  37. Vitamin and Mineral Deficiencies and Diseases

  38. Vitamin and Mineral Deficiencies

  39. Toxicity of Minerals and Vitamins • High levels of fluoride can be toxic • Fluorosis • Kidney Disease • More harmful to babies

  40. Water • People die within days of not having water • Makes up about 65% of your body weight • The body’s most important functions take place in water • Makes up most of the body’s fluids • Nutrients are dissolved in water in blood and transported around the body • Perspiration • Need about 2 liter s of water per day • Need more if weather is hot or your are exercising

  41. Because it is mostly water, the filling of a hot apple pie is much more likely to burn your tongue than the crust. Water releases a lot of heat as it cools. During freezing weather, farmers protect citrus crops by spraying them with water.

  42. Thermochemistry Thermochemistry is the study of energy changes that occur during chemical reactions and changes in state. • The energy stored in the chemical bonds of a substance is called chemical potential energy. • Heat, represented by q, is energy that transfers from one object to another because of a temperature difference between them. • Heat always flows from a warmer object to a cooler object.

  43. Energy Transformations • In an endothermic process, the system gains heat as the surroundings cool down. • In an exothermic process, the system loses heat as the surroundings heat up. • A system as the part of the universe on which you focus your attention. • The surroundings include everything else in the universe. • The law of conservation of energy states that in any chemical or physical process, energy is neither created nor destroyed.

  44. Heat Flow • Measured in two common units 1. the calorie 1 cal = 4.184 J 2. the joule 1 J = 0.2390 cal • The energy in food is usually expressed in Calories. • (1 Calorie = 1 kilocalorie = 1000 calories)

  45. Heat Capacity • Depends on both its • mass • chemical composition. • The amount of heat needed to increase the temperature of an object exactly 1°C is the heat capacity of that object.

  46. Specific Heat The specific heat capacity, or simply the specific heat (“c”), of a substance is the amount of heat it takes to raise the temperature of 1 g of the substance 1°C. Specific heat typical unit of measure is degrees Celsius is used!

  47. Calorimetry Calorimetry is the precise measurement of the heat flow into or out of a system for chemical and physical processes. • In calorimetry, the heat released by the system is equal to the heat absorbed by its surroundings. Conversely, the heat absorbed by a system is equal to the heat released by its surroundings.

  48. The insulated device used to measure the absorption or release of heat in chemical or physical processes is called a calorimeter. • The heat content of a system at constant pressure is the same as a property called the enthalpy (H) of the system.

  49. Energy Transformations: Digestion • Begins in Mouth • Mechanical – Grinding of food, muscles in mouth • Chemical - Digestion of starches begins with enzymes in salivary glands To Esophagus Mechanical - Peristalsis – Involuntary Movement of food through the esophagus To Stomach Chemical – Triggered by hormones, Acids and Enzymes breakdown foods Mechanical – Stomach churns food into chyme Electrical – Nerves signal movement of organs

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