METABOLISM AND NUTRITION By: Tallie and Bella

VOCAB  Acetyl-CoA: A molecule formed from pruvic acid in the mitochondria when oxygen is present; a key molecule in the metabolism of carbohydrates, proteins, and lipids.  Anabolism: Building up, or synthesis, reactions that require energy and make complex molecules out of two or more smaller ones; opposite of catabolism.  Basal metabolic rate: Amount of energy that is necessary to maintain life and keep the body functioning at a minimal rate.  Catabolism: reactions that break down large molecules into two or more smaller ones with release of energy; opposite of anabolism  Citric acid cycle: Aerobic series of reactions that follow glycolysis in glucose metabolism to release energy and carbon dioxide; also called Krebs cycle.

VOCAB PART 2  Complete protein: a protein that contains all of the essential amino acids.  Core temperature: the temperature deep in the body; temperature of the internal organs.  Glycolysis: Anaerobic series of reactions that produces two molecules of pyruvic acid from one molecule of glucose; first series of reactions in the catabolism of glucose.  Thermogenesis: Production of heat in response to food intake.

INTRODUCTION  Metabolism – the sum of all chemical reactions in the body. Within a cell, the reactions are called cellular metabolism. Enzymes speed up the reactions.  Nutrition – the acquisition, assimilation, and utilization of the nutrients that are contained in food.

METABOLISM OF ABSORBED NUTRIENTS  Anabolism uses energy to build large molecules break down into smaller ones. Catabolic reactions within the cell that release energy for use by the cell are termed cellular respiration  Catabolism releases energy when large molecules break down into smaller ones.

BASIC STEPS IN GLYCOLYSIS, CITRIC ACID CYCLE, AND ELECTRON TRANSPORT 1.The catabolism of glucose is glycolysis, which takes place in the cytoplasm, which takes place in the cytoplasm and is anaerobic. 2.Two pyruvic acid molecules are produced from one molecule of glucose and there is a net gain of 2 ATP. 3.If oxygen is present, pyruvic acid enters the mitochondria for the aerobic phase of cellular respiration. 4.The pyruvic acid is incorporated into acetyl-CoA, which enters the citric acid cycle. 5.The complete breakdown of glucose produces 36 – 38 ATP.

HOW IS ENERGY FROM FOOD MEASURED?  Energy from food is measured in Calories. One Calorie is the amount of energy required to raise the temperature of one kilogram of water from 14 degrees Celsius to 15 degrees Celsius.

ESSENTIAL AMINO ACIDS AND NONESSENTIAL  Essential amino acids must be supplied in the diet; they cannot by synthesized in the body.  Nonessential amino acids can by synthesized from other amino acids that are available.  Complete proteins contain all the essential amino acids.  Incomplete proteins lack one or more of the essential amino acids. In complete proteins should be eaten in combination that provide all the essential amino acids.

BASIC ELEMENTS OF NUTRITION  Carbohydrates: provide energy, add bulk to the diet, and are used to synthesize other compounds  Proteins: provide structure, regulate the body.  Lipids: an important source of energy provide essential fatty acids, transport vitamins, are components of certain structural elements, providing head insulation, and form protective cushions.

CONT.  Fiber is important because is adds bulk to the diet, enhances absorption or nutrients, and helps move the feces in the large intestine. (Many diseases are related to decreased dietary fiber).  Vitamins: organic molecules that are necessary for good health.  Minerals: inorganic substances that are necessary in small amounts to maintain good health  Water: essential component of the diet the average adult requires about 2.5 liters of water each day. Water is integral part of body cells, providing a medium for chemical reactions, is a transport medium, is a lubricant, and helps maintain body temperature.

BODY TEMPERATURE  Core temperature: the temperature of the internal organs  Shell temperature: the temperature of the body surface  Heat is produced by the catabolism of nutrients. The body produces additional heat by muscular contraction (shivering) and increasing metabolic rate (Hormones). Heat is conserved by constriction of cutaneous blood vessels, which keeps the blood warmer by keeping it away from the cold surface body.  Heat is lost from the body through radiation, conduction, convection, and evaporation.  Body temperature is regulated by a homeostatic negative feedback mechanism that is integrated by the hypothalamus of the brain.

CHAPTER RECALL 1)Anaerobic catabolism of glucose 2)Acquisition, assimilation, and utilization of nutrients 3)Smaller molecules react to produce larger molecule and water 4)Production of glycogen from glucose 5)Process in catabolism of fatty acids 6)Temperature of internal organs 7)A,D,E,K 8)Glucose, fructose, and galactose 9)Produces ammonia and a ketaoacid from an amino acid 10)Production of heat in response to food intake A)Beta Oxidation B)Core temperature C)Deamination D)Dehydration Synthesis E)Fat-soluble vitamins F)Glycogenesis G)Glycolysis H)Monosaccharides I)Nutrition J)Thermogenesis

RECALL ANSWERS 1)Anaerobic catabolism of glucose 2)Acquisition, assimilation, and utilization of nutrients 3)Smaller molecules react to produce larger molecule and water 4)Production of glycogen from glucose 5)Process in catabolism of fatty acids 6)Temperature of internal organs 7)A,D,E,K 8)Glucose, fructose, and galactose 9)Produces ammonia and a ketaoacid from an amino acid 10)Production of heat in response to food intake 1) Glycolysis 2) Nutrition 3) Dehydration Synthesis 4) Glycogenesis 5) Beta Oxidation 6) Core temperature 7) Fat-soluble vitamins 8) Monosaccharides 9) Deamination 10) Thermogenesis