TOPIC 3 Energy systems 2 Relationship Between Nutrition

TOPIC 3 Energy systems

2 Relationship Between Nutrition, Environment and Health External Environment Religion Food Security/Insecurity Culture Agriculture Politics Economics Education Health Service Social Status Food Security/Insecurity Nutritional Status Optimal Nourished Under-nourished Over-nourished Malnourished Nutritional Requirements Growth and Development Pregnancy and Lactation Internal Environment Sport and Exercise Elderly DNA/RNA Cells Organs Central Nervous System Metabolism Disease

3. 1. 1 List the macronutrients and micronutrients. � Macronutrients are nutrients that provide calories or energy and are required in large amounts: Lipid (fat) carbohydrate and protein. � Micronutrients are nutrients required by humans in small amounts to orchestrate a wide variety of physiological functions but are not made by the organism Vitamins Minerals Water Fiber

Carbohydrates 4 � Food Sources Include: Functions: � cereals � sweeteners Fuel for your body � fruit Energy storage � dairy � bread � Rice � Grains

Fat 5 � Food Sources Include: Functions: � Meat � Dairy Products Fuel storage � oil Hormones � nuts Cell storage � bacon � margarine, butter

Protein 6 � Food Sources: � Meat � Chicken � Fish � Eggs blocks � Cheese � Milk � Beans � Tofu (soy) Functions: Structure Storage Enzymes Muscle building

Water 7 � Food Sources � Beverages � Fruits � Vegetables � Ice Cream Reactions Functions: Excretion Lubrication Transport Medium for

Vitamins 8 � Food Sources Functions: � Fruits Energy release from macronutrients � Vegetables Immune function � Fatty Fish Eyesight � Bone Health

Minerals 9 � Food Sources: � Fruits teeth � Vegetables � Fatty Fish � Milk Functions: Mineralization of bones and Blood oxygen transport Defense against free radicals Acid base balance

3. 1. 3 State the chemical composition of a glucose molecule. � Glucose – monosaccharide Carbon, Hydrogen and Oxygen. � It’s chemical formula is C 6 H 12 O 6 � 1: 2: 1 ratio �

3. 1. 5 Explain how glucose molecules can combine to form disaccharides and polysaccharides

Carbohydrates 12 � � � Monosaccarides have one sugar molecule � fruits, vegetables and honey Disaccharides have 2 sugar molecules � sugar, milk Polysaccharides have many sugar molecules � rice, potatoes, corn and wheat

Condensation Reaction 13 � � � the linking of a monosaccharide to another monosaccharide, disaccharide or polysaccharide by removal of a water molecule Joule: a unit of energy (just like a calorie). Joule is the energy obtained from food. 1 calorie = approximately 4 joules

Test Your Knowledge: 14 � Place the major CHO sources with the correct country: � sweet potato � maize � cassava � wheat � rice � potato

3. 1. 6 State the composition of a molecule of triglycerol. � Also known as triglyceride which is a lipid/fat � consists of a glycerol and 3 fatty acid chains � Stored in adipose tissue and skeletal muscle

Structure of triglycerol. glycero l Saturated Fatty acid Unsaturated Fatty acid

3. 1. 7 Distinguish between saturated and unsaturated fatty acids What difference do you notice between the two?

18 Unsaturated vs Saturated Fatty Acids Unsaturated Saturated Double bonds No double bonds between carbon atoms Come from plant based foods Come from animal sources Examples include peanuts, cashew nuts, rapeseed and sunflower oil, olive oil and avocado Tropical oils such as coconut and palm oil. Fat in and around meat, chicken, pork Liquid at Room Solid at Room

To Think About: Trans Fat 19 Describe a trans fat. � Why is this harmful? � Should the government have put a ban on foods with trans fat? Why or why not? � Discuss with your elbow partner. �

3. 1. 8 State the chemical composition of a protein molecule. � � � Protein molecules consist of Carbon, Hydrogen, Oxygen and Nitrogen. The smallest part of a protein is called an amino acid. There are 20 different amino acids Compose blood tissue, muscle tissue, hormones and enzymes

3. 1. 9 Distinguish between an essential and a nonessential amino acid. � � � Essential amino acids NOT synthesized by the human body and must be obtained by diet Non-essential amino acids can be synthesized by the human body How would this impact a vegetarian?

22 3. 1. 10 Describe current recommendations for a healthy balanced diet � � � Balanced diet: a diet that provides all nutrients in the right amount in order to maintain health and prevent nutrient excess or deficiency diseases Dietary recommendations: recommended amounts of essential nutrients in the diet Dietary guidelines: recommended amounts of foods, food groups or meals

3. 1. 10 Describe current recommendations for a healthy balanced diet.

My Plate

Student Thinking Questions 25 � � � Complete the student thinking questions found in your student workbook. Research of dietary recommendations between two countries of your choice. What are the similarities and differences between the two countries? Why do you think there are differences? Once you have finished, complete the questions 1 - 4 under research of dietary

3. 1. 13 State the energy content per 100 g of carbohydrate, lipid and protein. � � Energy in 100 grams: � Carbohydrate = 1600 k. J (400 calories) � Protein = 1700 k. J (400 calories) � Fat =3700 k. J (900 calories) Both carbohydrates and lipids can be used for energy storage in humans. Carbohydrates are usually used for energy storage over short periods and lipids for long term storage.

Observe the following chart. What do you notice among the nutrients?

3. 1. 12 Discuss how the recommended energy distribution of the dietary macronutrients differs between endurance athletes and nonathletes. � � � Using your textbook, complete the chart found on your student workbook. “the more glycogen, the further and faster the player ran”-what does this quote mean to you? Review your chart—describe what the information means to you in your daily life? How could you use this information to better train an athlete?

Carbs During prolonged, aerobic exercise, energy is provided by the muscle glycogen stores – which directly depend on the amount of carbohydrates ingested. � This is not the only reason why dietary carbohydrates play a crucial role in athletic performance; they have also been found to prevent the onset of early muscle fatigue and hypoglycaemia during exercise. �

Carbs By keeping carbohydrate intake high, an athlete therefore replenishes his glycogen energy stores, and reduces the risk of rapid fatigue and a decline in performance. � At the same time, carbohydrate intake should not be so high as to drastically reduce the intake of fat, because the body will use fat as a substrate once glycogen stores are depleted. �

Protein � The use of body protein in exercise is usually small, but prolonged exercise in extreme sports can degrade muscle, hence the need for amino acids during the recovery phase.

3. 2. 1 Outline the terms metabolism, anabolism, aerobic catabolism and aerobic catabolism. � � � Metabolism: All the biochemical reactions that occur within an organism, including anabolic and catabolic reactions Anabolism: Energy requiring reactions whereby small molecules are built up into larger ones Catabolism: Chemical reactions that break down complex organic compounds into simpler ones, with the net release of energy. Aerobic catabolism refers to processes which require oxygen. Anaerobic catabolism is independent of the presence of oxygen.

3. 2. 2 State what glycogen is and its major storage sites. � � � Glycogen comes from the Greek world glykr meaning “sweet” Animals store polysaccharides as glycogen in the liver and muscle. When the diet provides more glucose than the tissue requires, your body stores glucose as glycogen.

3. 2. 3 State the major sites of triglyceride storage. � Major storage site of triglycerides are adipose tissue (fat) and skeletal muscle.

3. 2. 4 Explain the role of insulin in the formation of glycogen and the accumulation of body fat. � � � Insulin is a hormone that informs the body’s cells that the animal is well fed Causes liver and muscle cells to take in glucose and store it in the form of glycogen Causes fat cells to take in blood lipids and turn them into triglycerides

3. 2. 4 � � Ingest cabohydrates > increase in blood glucose > insulin is released by pancreas After a meal, insulin concentrations rise and cells uptake glucose thereby decreasing the level of glucose in the blood

Exercise and Insulin 37 � � In response to exercise, we need muscle to use glycogen and not store it in muslce and liver When you exercise, insulin concentration goes down

Visual

3. 2. 5 Outline the terms glycogenolysis and lipolysis. Glycogenolysis the breakdown of glycogen to glucose. � In the liver, the breakdown of glycogen results in elevated blood glucose. � In the muscle, the breakdown of glycogen is used by the muscle for energy. There is no release of glucose into the blood stream from the muscle. � This occurs as a result of the hormone glucagon. �

Lipolysis � � Lipolysis is the process of releasing triglycerides from the body’s fat stores Excess fat is stored in adipose tissue and muscles Free fatty acids are released into the blood stream and throughout the body breakdown of adipose tissue by glucagon and adrenaline to increase blood sugar

3. 2. 6 Outline the functions of glucagon and adrenaline during fasting and exercise.

3. 2. 6 � � During fasting and exercise the blood glucose level drops and therefore the release of glucagon and adrenaline will result in an increase of blood glucose. Glucagon and adrenaline stimulate the breakdown of glycogen in the liver to increase blood glucose levels during long periods of exercise and times of fasting

3. 2. 7 Explain the role of insulin and muscle contraction on glucose uptake during exercise. Insulin will result in an increased uptake of blood glucose into the liver and muscle. � Muscle contraction will also result in an increase of blood glucose uptake from the blood due to higher energy demands. �

3. 3. 1 Draw a diagram to show the ultrastructure of a generalized animal cell. With ribosomes Apparatus

3. 3. 2 Draw a diagram to show the ultrastructure of a mitochondrion.

3. 3. 3 Define the term cell respiration. � The controlled release of energy in the form of ATP

Cell and Energy Metabolism

3. 3. 4 Explain how adenosine can gain and lose a phosphate molecule. � � � ATP is made up of adenosine and three phosphate groups ATP releases a great deal of energy when their bonds are broken ATP is the energy currency of the cell

ATP

50 Draw the following diagram in your workbook � ENERGY IN ADENOSINE � � P P + P P ENERGY OUT ADENOSINE P P P

3. 3. 5 Explain the role of ATP in muscle contraction. Muscle contraction requires lots of energy � All muscle fibers have the capacity to produce ATP using carbohydrates and fats � The release of energy caused by the breakdown of ATP to ADP provides the energy for muscle contraction. � In muscle there is sufficient ATP present to allow just two seconds of muscle activity �

ATP in Muscle Contraction � � After the two seconds, the muscle must use ATP from another source This energy (ATP) comes from different energy systems

3. 3. 6 Describe the re-synthesis of ATP by the ATP-CP system (creatinine phosphate system) Creatine phosphate (a high energy molecule) is broken down to provide a phosphate molecule for the re-synthesis of ATP during the initial stages of exercise � Occurs quickly and is important during hard exercise � Short lived—works for 20 seconds and then you need another way of getting ATP � Give an example of during what sport you may use this energy system? �

3. 3. 6 Describe the re-synthesis of ATP by the ATP–CP system.

3. 3. 7 Describe the production of ATP by the lactic acid system Also known as anaerobic glycolysis—the breakdown of glucose to pyruvate without the use of oxygen. Pyruvate is then converted into lactic acid, which limits the amount of ATP produced (2 ATP molecules). � The lactic acid system is generally used for high to medium intensity activities lasting no longer than 2 minutes. � Lactic acid accumulates in the muscle and causes discomfort and reduces the ability of muscle to contract > slow down �

3. 3. 7 Describe the production of ATP by the lactic acid system.

3. 3. 8 Explain the phenomena of oxygen deficit and oxygen debt � � � � Oxygen debt now excess post exercise oxygen consumption (EPOC) These terms refer to a lack of oxygen while training Oxygen Deficit. While exercising intensely the body is sometimes unable to fulfill all of its energy needs. In order to make up the difference without sacrificing the output, the body must tap into its anaerobic metabolism. This where the body goes into a mix of aerobic and anaerobic energy production. While not hugely detrimental, oxygen deficits can grow to a level that the anaerobic energy system cannot cover. This can cause performance to deteriorate.

Oxygen Debt This term describes how the body pays back its debt incurred above after the exercise is over. � You will notice that even after you have finished racing you will continue to breath hard. � At this point your body is still trying to repay the oxygen debt that was created when you were working hard. � Technically, it is excessive post-exercise oxygen consumption (EPOC). �

Describe the differences between these two diagrams

3. 3. 9 Describe the production of ATP from glucose and fatty acids by the aerobic system. Within the Mitochondria is the Krebs cycle and electron transport chain > produce ATP from all main food groups-usually carbs and fats � Proteins are used for 15 percent of resting energy metabolism � Fats are broken down by beta oxidation that also liberates electrons to produce ATP (energy) �

3. 3. 9 Key Points 61 � Beginning of exercise: � anaerobic system that dominates energy provision � ATP within muscle provides energy for 2 seconds � Creatine phosphate fades after 20 seconds � Then lactic acid system dominates but is short lived � Finally aerobic energy system dominates � Fats are only used during aerobic activities

Aerobic system

A comparison of anaerobic and aerobic glycolysis-Draw this in your workbook

3. 3. 10 Discuss the characteristics of the three energy systems and their relative contributions during exercise

3. 3. 11 Evaluate the relative contributions of the three energy systems during different types of exercise. Independent research: � Using the diagrams in your student workbook, your textbook and the internet, compare three energy systems with 3 different types of exercise: � ATP-PC � LACTIC ACID � OXYGEN �