Presentation on theme: "Chemical Compounds in Cells and in Our Food pp & pp"— Presentation transcript:
1 Chemical Compounds in Cells and in Our Food pp 52-55 & pp 505-517
2 Review of basic chemistry Element – any substance that cannot be broken down into a simpler substanceEx – carbon, nitrogen, oxygen, hydrogenAtom – smallest unit of an elementCompound – two or more elements chemically combinedEx – water, sugar, starchMolecule – smallest unit of most compoundsEx – H2O, C6H12O6, O2, CO2
3 Inorganic Compounds Don’t contain Carbon, Hydrogen, and Oxygen Ex – water (H2O), salt (Sodium chloride), CO2
5 Proteins Contain C, H, O, N and sometimes Sulfur Found in many foods In the cell, used as: part of cell membranesstructures of organellesmuscles in the body
6 Structure of Proteins Made of amino acids There are 20 different amino acids in living thingsThese aa’s link together to form a large molecule of aa’s in one protein.Change one aa, changes whole 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 Carbohydrates Energy rich C, H, and O Simple sugars - glucose Complex carbohydrates – made up of many simple sugars attached to each otherStarchCellulose – make up plant cell wallsFound in cell membranes, other cell parts, and store energy
10 Lipids Fats, oils, waxes Store energy Made of C, H, and O Contain more energythan carbs
11 Nucleic Acids DNA = deoxyribonucleic acid RNA – ribonucleic acid Made of C, H, O, N, and PhosphorusContain instructions for cells to carryout all their functions.
12 Water Makes up about two thirds of your body. Most chemical reactions occur in water.Essential for all life.
13 Food and Digestion- pp 504-530 Why do we need food?Material for growth, repairEnergyAllows body to maintain homeostasis
14 Nutrients – substances in food that provides body with raw materials and energy to carry out essential processesCarbohydratesFatsProteinsVitaminsMineralsWater
15 Energy Carbs, fats and proteins provide body with energy Amount of energy in food measured in caloriesOne calorie is the amount of energy to raise the temperature of 1 gram of water 1 degree Celsius
16 Calorie or calorie? Calorie – used to measure energy in foods. 1 Calorie = 1000 caloriesEx – 1 apple contains 50 Calories or 50,000 calories.The more calories a food has, the more energy it contains.
17 Amount of Calories needed? Depends on physical needs and age of the personVery active people need moreInfants and small children need moreOlder people need fewer
18 Carbohydrates 1 gram carbohydrates provides 4 Calories of energy Provide raw materials to make cell partsTwo groups:Simple carbohydratesComplex carbohydrates
19 Simple Carbohydrates = Sugars Found in fruits, vegetables, milkGlucose (C6H12O6) – major source of energy for your cells.Another simple sugar = fructose in fruits
20 Complex Carbohydrates Made of many simple sugars connectedStarch – found in potatoes, wheat, rice, cornFiber (Cellulose) – found in plants, but cannot be digested and passes through your digestive system - helps keep things moving along.
21 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 nutrientsFoods with lots of sugar usually have fewer other useful nutrients
22 FATS Contain more than 2x the energy of carbohydrates Store energy Parts of cellsProtect internal organsInsulate the body
23 Types of Fats Unsaturated Fats Saturated Fats Liquid at room tempreratureOilsConsidered good for youSaturated FatsSolid at room temperatureFrom animals; a few plants –coconut palmBad for you
24 Cholesterol Saturated fat found in meat, eggs, cheese, etc Necessary for cell membranes in animalsNot needed in diet; liver makes all that is needed.Can clog arteries and lead to heart attack
25 How much fat do we need?Should have no more than 30% of Calories in diet from fatShould particularly limit intake of saturated fats and cholesterolRead 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
26 Proteins in the diet For tissue growth and repair Enzymes speed up chemical reactionsCan be used for energy, but not usuallyAbout 12% of your daily Calorie intake should be protein
27 Amino Acids The body makes about half the amino acids it needs Rest come from foodComplete proteins -contain allof the essential amino acidsMeat and eggsIncomplete proteins – missingone or more essential amino acidBeans, grains, and nuts
28 VitaminsAct as helper molecules for a variety of chemical reactions in the body.The body makes some – K is made by bacteria in intestineThe rest come from foods – eating a wide variety of foods provides all the vitamins needed.
29 Types of vitamins – chart p 511 Fat soluble vitaminsDissolve in fatty tissue and are stored there.Includes vitamins A, D, E and KWater soluble vitaminsDissolve in water and not stored in bodyNeeded in diet every day.Includes vitamins B and C
30 Minerals Nutrients not made by living things In soil and absorbed by plantsIncludes calcium and ironSee chart - 512
31 Water People die within days of not having water Makes up about 65% of your body weightThe body’s most important functions take place in waterMakes up most of the body’s fluidsNutrients are dissolved in water in blood and transported around the bodyPerspirationNeed about 2 liter s of water per dayNeed more if weather is hot or your are exercising
32 Food Guide Pyramid Classifies food into 6 groups and indicates how many servingsfrom each groupshould be eaten per day
33 Food LabelsAllow you to evaluate a single food as well as compare the nutritional value of two foods.Tells:Serving sizeCalories from fat% daily value of one servingingredients