2Section Objectives:Interpret the different functions of the digestive system organs.Outline the pathway food follows through the digestive tract.Identify the role of enzymes in chemical digestion.
3Functions of the Digestive System The main function of the digestive system is to disassemble the food you eat into its component molecules so that it can be used as energy for your body.Digestion is accomplished through a number of steps.
4Digestionchemical process by which food is broken down into smaller molecules used by the body.
447. Pancreas secretes pancreatic fluid into the small intestine. Helps digest fats, proteins, and carbohydrates. Pancreatic fluid is a mixture of enzymes and sodium bicarbonate.Insulin controls the uptake of glucose by the cells.
458. LiverLargest internal organ, serves as the body’s primary storage place main chemical factory and detoxification site.Gets blood from intestines before the blood goes to the rest of the body.Cross-section of a normal liver.The holes are bile ducts.
47LiverHepatitis - infection of the liver by a virus. Can be sexually transmitted, by blood products, or feces.Hepatic Cell Carcinoma
48LiverCirrhosis - scarring of the liver, can be caused from Hepatitis or alcoholism.Results can be death.Cirrhosis
499. Gall Bladderstores bile made by the liver. Takes water from solution making bile more concentrated. Bile then is released into small intestine as needed.stone that stuckinto the cystic ductGall stones
50Gall Bladder cont. Calcified Stones taken out from surgically removed
55Section Objectives:Recognize the contribution of the six classes of nutrients to body nutrition.Identify the role of the liver in food storage.Relate caloric intake to weight loss or gain.
56The Vital NutrientsSix basic kinds of nutrients can be found in foods: carbohydrates, fats, proteins, minerals, vitamins, and water.You supply your body with these nutrients when you eat foods from the five main food groups.
621. SugarsA. Glucose - sugar cells obtain most of their energy from C6H12O6.B. Glycogen - made up of thousands of glucose units.(Body stores glycogen in the liver and muscles, if an excess then stored as fat.)
632. Starches made of many sugars. Aka complex carbs. Ex: Breads, pasta and potatoes.
643. Cellulose/Fibercontained in cell walls of plants. Fiber that aids in digestion. May help provide some protection against heart disease and some types of cancer.
65B. Fats - Lipidsstore other nutrients and are a source of stored energy.Made of three fatty acids joined by glycerol molecule.Use lipids to make cell membranes, hormones, oils in hair and skin.Two types - Saturated and Unsaturated fats.(Unsaturated fat is considered the healthier of the two, because it is liquid at room temperature.)
66C. Proteinsthe construction materials for the body parts such as muscle, skin and blood.1. Amino Acids - make up proteins.There are 20 Amino AcidsNote: Essential amino acids can not be made by the body, there are eight of these. A proper diet would provide these for the body. Foods such as meats, eggs and dairy products contain them.
67Minerals and vitamins Fluorine (F) Calcium (Ca) Iodine (I) Phosphorus (P)Iron (Fe)Copper (Cu)Sodium (Na)Potassium (K)Magnesium (Mg)Sulfur (S)
68D. Vitaminscomplex organic molecules that are needed by the body in very small amounts.Two types:1. Water soluble - dissolve in water. Cannot be stored in the body, so must have regularly. Ex: B1(Thiamin), B2 (Riboflavin), Niacin, B6, B12, C.2. Fat Soluble - stored in fat or liver for future use by the body. Ex: Vit. A, D, E, K
69This table lists foods that contain fat-soluble and water-soluble vitamins. FunctionSourceFat-solubleAMaintain health of epithelial cells; formation of light absorbing pigment; growth of bones and teethLiver, broccoli, green and yellow vegetables, tomatoes, butter, egg yolkDAbsorption of calcium and phosphorus in digestive tractEgg yolk, shrimp, yeast, liver, fortified milk; produced in the skin upon exposure to ultraviolet rays in sunlightEFormation of DNA, RNA, and red blood cellsLeafy vegetables, milk, butterGreen vegetables, tomatoes, produced by intestinal bacteriaKBlood clotting
70Minerals and vitamins Vitamins Function Source Niacin Water-solubleB1Sugar metabolism; synthesis of neurotransmittersHam, eggs, green vegetables, chicken, raisins, seafood, soybeans, milkB2 (riboflavin)Sugar and protein metabolism in cells of eyes, skin, intestines, bloodGreen vegetables, meats, yeast, eggsNiacinEnergy-releasing reactions; fat metabolismYeast, meats, liver, fish, whole-grain cereals, nutsB6Fat metabolismSalmon, yeast, tomatoes, corn, spinach, liver, yogurt, wheat bran, whole-grain cereals and bread
71Protein metabolism; wound healing Minerals and vitaminsVitaminsFunctionSourceWater-solubleB12Red blood cell formation; metabolism of amino acidsLiver, milk, cheese, eggs, meatsPantothenic acidAerobic respiration; synthesis of hormonesMilk, liver, yeast, green vegetables, whole-grain cereals and breadsFolic acidSynthesis of DNA and RNA; production of red and white blood cellsLiver, leafy green vegetables, nuts, orange juiceBiotinAerobic respiration; fat metabolismYeast, liver, egg yolkCProtein metabolism; wound healingCitrus fruits, tomatoes, leafy green vegetables, broccoli, potatoes, peppers
73E. Mineralsinorganic substances that perform vital functions in the body.Calcium - found in dairy products . Necessary for strong bones and teeth, muscle and nerve activity and blood clotting.Potassium , Sodium , and Magnesium - Necessary for nerve and muscle activity.
74F. Waternecessary for life. Lose 3-5 liter of water a day through sweat , urine, etc.About 67% of your body mass is water.90% of the plasma is water.
75F. Water 3 Functions: 1. To transport nutrients and wastes 2. Cool body3. Necessary for chemical reactions.
79Calorieamount of heat energy needed to raise the temperature of 1 gram of water by 1oC Measurement for energy.
80Calories and Metabolism The energy content of food is measured in units of heat called Calories, each of which represents a kilocalorie, or 1000 calories.Some foods, especially those with fats, contain more Calories than others.
81Metabolic RateBasal Metabolic Rate (BMR) - rate of metabolism at rest. BMR is equal to the numbers of kilocalories an animal uses in a set amount of time to maintain homeostasis.
844 Diseases from poor nutrition 1. Scurvy - caused from a lack of Vit. Cdisease sailor once got because of the long voyage and poor diet.
85Scurvy - vitamin C deficiency. The effects of scurvy
864 Diseases from poor nutrition cont. 2. Night Blindness - caused from lack of Vit. A3. Beriberi - Lack of B1. Most common in Asia where diet is mainly rice.4. Rickets - caused from lack of Vit. D.Rickets
872 Eating Disorders1. Bulimia - consume lots of food, but then binge. Possible problems, swollen salivary glands, kidney, liver and pancreas problems, tooth decay from stomach acid.2. Anorexia - over exercise, but does not eat. Starvation occurs.
90Endocrine glandsseries of ductless glands that release chemicals (hormones ) directly into the blood stream.
91HormonesChemicals released in one part of an organism that affects another part. (Chemical messengers)
92Two groups of hormones based on how they act on their target cells. A. Amino acid hormones - amino acids make proteins.B. Steroid hormones - made from lipids . Can alter genetic activity of some cells.
93Hypothalamus - portion of the brain that controls the pituitary gland. Indirectly controls growth, development and activities of the reproductive system.
94Negative feedback system - self regulating system of the endocrine system. As the hormone increases level in the blood production of the hormone at the gland decreases. (equilibrium)
95Oxytocin -for uterus contraction during birth. (stored in the posterior pituitary gland)
96Pituitary gland -master endocrine gland - growth hormone produced here. Indirectly controls growth, development and activities of the reproductive system.Controls many other glands.
98hGH - human growth hormone - stimulates division and growth of bone, muscle, and other body cells. Stimulates liver cells to release glucose (for energy) into blood during times of growth.
99Robert Pershing Wadlow - Giant Robert Pershing Wadlow was born on Feb. 22, 1918 in Alton, Illinois. At the time of his death at age 22, he was 8' 11.1" tall & 490 pounds, which made him the tallest person in history according to the Guinness Book of Records.
100His parents, Addie and Harold Wadlow, always loved & protected him to the best of their abilities, honoring his desire to be treated as a "normal" person. They even destroyed his personal belongings after his death so that no one could profit from the exploitation of them. Robert promoted the International Shoe Company, which provided his size 37 shoes to him for free. Traveling for the shoe company, he visited over 800 towns and 41 states.
101Robert's size was attributed to an overactive pituitary gland, which produced much higher than normal levels of growth hormone. Because of the extremely long legs caused by pituitary giantism, he had little sensation in his feet and did not feel any chafing until blisters formed. While making an appearance in 1940, a fatal infection set in when such a blister formed due to the braces he had to wear to strengthen his overly long legs. On the 15th of July, Robert Wadlow passed away in his sleep from the infection.