SBI3C Ms. De Sousa

Introduction to Systems The human body is like a motorcyle. There are many systems (parts of the motorcycle) that work together to help it function properly If one system fails, the well being of hte human body is compromised.

Introduction to Systems In order for the systems to work effectively humans need to be healthy. What does it mean to be healthy? Need to be physically active Need to have a well balanced diet

Energy Source In order for an individual to be physically active, he/she must eat. Food is a source of energy that is broken down by the body and used for growth, maintenance and repair.

Caloric intake per day Age Sedentary 1 Level 1 Low Active 2 Level 2 Active 3 Level y y y y y y y y y y Males Age Sedentary Level Low Active Level Active Level 2-3 y y y y y y y y y y Females

Male vs. Females The amount of energy that people require depends on their : 1) physical activity levels 2) medical conditions 3) Female vs. Male Males usually have higher energy needs and must consume more energy (i.e. food) compared to females.

Food intake Food supplies the energy required for the body to function properly. If you eat more food than needed, the body will store it as surplus fat. Fat provides twice the energy of an equivalent mass of carbohydrates.

Canada’s food guide

Balanced diet Vegetables and Fruits: At least one dark green and one orange vegetable each day. Enjoy vegetables and fruit prepared with little or no added fat, sugar or salt. Have vegetables and fruit more often than juice.

Grain Products: Make at least half of your grain products whole grain each day. Choose grain products that are low in fat, sugar or salt. Balanced diet

Milk and Alternatives: Drink skim, 1% or 2% milk each day. Two cups of milk everyday for adequate vitamin D. Select lower fat milk alternatives. Balanced diet

Meat and Alternatives: Have meat alternatives such as beans, lentils and tofu often. Eat at least two Food Guide Servings of fish each week. Should be prepared with little or no added fat or salt. Balanced diet

A Balanced Diet

Essential Nutrients Our body requires essential nutrients so that it can grow and repair damaged tissues. Therefore, it is important for us to eat a balanced diet so that we can obtain these essential nutrients. There are 2 major groups of nutrients that are essential to our diet:. 1) Macromolecules: a very large organic molecule Need to be consumed in large amounts. Carbohydrates, proteins and fats. 2) Micronutrients: Only need small amounts Vitamins and Minerals

Carbohydrates Molecules that contain Hydrogen, Oxygen and Carbon Monosaccharides (simple sugars) or polysaccharides (complex sugars) Monosaccharides: Simple sugars Do not need to be broken down by the digestive system. Example: fructose and galactose. Polysaccharides: Complex Sugars Long chains of monosaccharides Example: starch

Macromolecules Monosaccharide Polysaccharide

Lipids (fats) Made up of carbon, hydrogen and oxygen Stores more energy than carbohydrates Saturated fats do not have a double bond and which makes it worse for your health Unsaturated fats have a double bond and are better for your health. Example: Fatty acid chains (long chains of carbon atoms)

Lipids (fatty acids)

Proteins Polymers made up of amino acids. There are 20 amino acids found in the foods we eat. 8 of those 20 amino acids are essential to our diets. Our body cannot produce them on our own. There are many proteins in our body and each one of them is different in terms of their shape, size and function.

Proteins