Organ How it aids in digestion Enzymes for chemical breakdown (where is it produced) What it breaks down/absorbs Aborption? Mouth Mechanically and chemically breaks down food Amylase - salivary glands Carbohydrates No Stomach Liver Small Intestine Pancreas Large Intestine

Putting It All Together We will start with basic molecules that are important to life. Elements: C = Carbon H= Hydrogen O= Oxygen N= Nitrogen Water = H2O This means we have 2 hydrogen and 1 oxygen. Therefore, we can say the ratio of hydrogen to oxygen is 2:1

What are Carbohydrates? Monosaccharides: Single sugars, main energy source for most organisms Ex. Glucose (C6H12O6)

Disaccharides: Double sugars, 2 monosaccharides, used for transport C6H12O6 + C6H12O6  C12H22O11 + H2O maltose: glucose + glucose (grain sugar) sucrose: glucose + fructose (table sugar) lactose: glucose + galactose (milk sugar) Polysaccharides: 3 or more sugars = Polysaccharides (C150H300O150) starches, store energy for later use. (Cellulose- Found in plant cell walls; Glycogen found in the liver of humans) O OH CH2OH

Where does energy come from? Chemical Energy: Energy stored in molecules. Breaking chemical bonds releases energy. Specifically C-H Bonds Metabolism – the building up and breaking down of molecules. Dehydration synthesis – (loss of water to build) One water molecule is lost as two molecules join. (- H removed from one subunit, - OH from another, 1 water formed for every each building block) Hydrolysis – One water molecule is used as two molecules break apart

What are Lipids? LIPIDS –glycerol and three fatty acids, Contains large numbers of C-H bonds, (high energy) used for energy storage FATS - (fats & oils) Saturated: contains maximum number of hydrogen atoms, rigid, animal fats - solids at room temperature Unsaturated: carbon skeleton contains double bonds (C= C) structurally kinked, nonrigid, vegetable oils - liquids at room temperature

What has more energy? Fats have more than two times the energy of a large starch; plants immobile, can have bulky storage (starch) Fat more compact (for moving animals), cushions organs, insulates.

Proteins PROTEINS – made of amino acids. There are 20 different amino acids, contain carbon, hydrogen, oxygen and nitrogen, makes up your muscles, used for storage, enzymes, made from DNA 50% of the body’s dry weight is protein ***Structure determines function: amino acid sequence determines how it works***

Water Glucose Amino Acid (building block of proteins) Glycerol + 3 Fatty Acids = Lipid (fat)

Proteins Carbohydrates Fats Vitamins Fiber Substance Source Use in the Body Proteins Milk, eggs, lean meats, fish, beans, peas, cheese Growth, repair and maintenance of tissue, manufacture of enzymes Carbohydrates Cereals, breads, fruits, vegetables Source of energy Fats Fatty meats, bacon, cheese, butter, nuts, vegetable oils Source of energy, energy storage Vitamins Butter, milk, lean meats, fruits, leafy vegetables Growth, chemical processes Minerals Iron Iodine Calcium Meats, liver, nuts, cereals Iodized salt, seafood Whole-grain cereal, meats, milk, table salt, vegetables Production of hemoglobin(red blood cells) Thyroid gland Strong bones and teeth Fiber Whole-wheat bread, bran, whole-grain cereals, fruits, vegetables, nuts Keeps digestive system healthy The digestive system from the human body systems series (AGC/United Learning)

How do we measure food energy Carbohydrates, lipids and proteins all give the body energy but how do we measure that energy? Calorie = unit for measuring the amount of heat energy a food will provide Cal = 1 kcal or 1000 calories

Energy in food Carbohydrates – 4 kcal/gram Lipids – 9 kcal/gram Proteins – 4kcal/gram (proteins are only used when carbs and lipids are all used up)

Calorimeter Q = m x c x t Q = calorie m = mass of water c = constant (1 g/1°) t = temp change

Video on calories

Ticket out the door Using what you now know about macromolecules answer the following question on half piece of paper. If you knew you couldn’t eat for three days and you had one last meal what types of food would you load up on and why?