1. Nutrition

2. Nutrients  Chemicals in food that cells need  Macronutrients - large amounts daily  Micronutrients - smaller amounts daily  Food contains some combinations of 6 kinds of nutrients

3. Macronutrients  3 kinds: 1. Carbohydrates  major source of energy  made of C, H, O  used for energy quickly  if energy not required stored for later use: glycogen in animals – stored in liver & muscles cellulose in plants – stored in cell walls

4. Types of Carbs 1. Monosaccharide – simple sugars ex glucose (and its isomers) broken down by mitochondria to release energy leftover C used to build new molecules 2. Polysaccharides – complex carbohydrates starches ex. grains, rice, potatoes etc broken down into simple sugars during digestion excess sugar stored as glycogen in liver to be broken down if sugar levels too low

5. 3. Cellulose  cell walls  fibre ex. fruits, vegetables, whole grains, etc.  body can’t break it down  ‘sweeps’ materials through the digestive system more quickly  reduces risk of heart disease & colon cancers

6. 2. Proteins  control every body function  enzymes – speed up reactions  made of combinations of over 20 amino acids  bodies can make 12 of these a.a  8 need to come from diet  important for vegetarians/vegans to get these

7. Types of Proteins TypeExample  Structuraltendons, cartilage, hair, nails  Contractilemuscles  Transporthaemoglobin, myoglobin  Storagemilk, nuts, seeds  Hormonalinsulin, growth hormone  Enzymecatalyses cells rxns  Protectionimmune response

8. How complex are proteins? The image on the right shows a ball- and-stick model of a single amino acid. In the top right corner are molecules of glucose and ATP, the energy molecule of the human body, for comparison.

9. 3. Lipids (Fats)  long-term energy storage  fat-soluble vitamins  insulate and protect organs  make up cell membrane  steroid hormones  made of fatty acids and glycerol  3 types: 1. Saturated Fatty Acids  is saturated (full) of H atoms, can’t bond with any more  it is solid at room temperature (animal fat)

10. 2. Unsaturated Fatty Acids  has room to bond with 2 more hydrogen  is liquid at room temp. (plant fats – oils) 3.Trans fats:  partially hydrogenated (added H) unsaturated fats  Solid at room temp, often used in frying fast foods  Even small amounts in our diet are linked to heart disease.

11. Micronutrients  2 kinds: 1. Vitamins:  organic nutrients (C)  allow bodies to assemble the 3 macronutrients  water soluble – not stored in body, need to consume every day. ex B, C  fat soluble – stored in fats ex A, D, E, K 2.Minerals:  inorganic  needed daily through food to keep body systems running properly

12. Water  most important nutrient  75% body mass is water  consumed in lg quantities on a regular basis.  every cell needs water to complete its processes  many body processes take place in or use water  lost through sweating, breathing, urination

13. NutrientSome Functions Carbohydrates Provide carbon chains for building other molecules; used as primary fuel source Proteins Provide raw materials for growth and repair, and to make enzymes and other proteins; help transport oxygen; may be used as a fuel Fats Provide raw materials for building cellular membranes, nerve cells, and certain hormones; used as fuel Vitamins Help growth of skin cells; improve night vision and blood clotting; metabolize energy; prevent cellular damage; increase absorption of other nutrients; assist enzymes Minerals Help form and maintain bones and teeth; maintain acid-base balance; metabolize energy; improve muscle function WaterMakes up the bulk of blood and other bodily fluids