Transcript Protein
Protein •Definition •Functions •Incomplete vs. Complete •Sources Introductory Video 1 Functions • Grows and repairs tissues • Regulates body functions • Transports nutrients and oxygen • Supplies energy when carbohydrates and fats don’t supply adequate amounts McGill Video 2 Structure Structure Structure of Amino Acids: McGill Video 3 Amino Acids •The main component of every cell in the human body •Amino Acids are the building blocks of Protein •20 Amino Acids •9 are Essential McGill Video Methionine Tryptophan Threonine Valine Isoleucine Leucine Proline Histidine Lysine Arginine Semi-essential – needed for children 4 Sources Essential/Complete Essential Amino Acids are required by animals but can only be supplied by the diet (not synthesized in the body) Animal sources • Supply all 9 essential Amino Acids •Examples: Chicken, Fish, Milk, Eggs *Soy* Incomplete Plant sources •Supply only a few essential Amino Acids •Examples: Peanut Butter, Legumes, Rice 5 Review the bar graphs below that represent the proportion of amino acids in corn and rice. These two food sources are considered to be incomplete proteins because: Combinations You can combine two incomplete sources of protein to make it complete. • Peanut Butter and Bread • Beans and Rice • Hummus and Pita Chips McGill Video 7 Amounts Too Much Protein in the Diet • Increases workload of the digestive system • Strains the liver and kidneys Ketosis – body burns fat instead of glucose for energy - causes organs to fail, gout, bad breath Too Little Protein in the Diet • Causes malnutrition, increased risk of infection • Could possibly cause early death Kwashiorkor – bloated stomach 8 RDA Recommended Dietary Allowance for Protein Grams/Day Children ages 1 – 3 Children ages 4 – 8 Children ages 9 – 13 Girls ages 14 – 18 Boys ages 14 – 18 13 19 34 46 52 Women ages 19 – 70+ 46 Men ages 19 – 70+ 56 Examples of Protein: 1 egg = 6 g 1 c. milk = 8 g 8 oz. yogurt – 11 g 1 c. beans = 16 g 3 oz. meat = 21 g 9 Calories per gram Protein = 4 calories/gram So how many estimated calories from protein does an egg contain? 6 grams x 4 calories = 24 calories 10 Calories per gram Protein = 4 calories/gram How many calories from protein are in a cup of milk? 11 Eggs – The “Perfect” Protein Why are Eggs considered the “perfect” protein? •Highest Quality Protein •Contain ALL 20 Amino Acids •Helps you feel full •Possesses many nutrients Benefit of Eggs Video 12 Parts of an Egg Parts of a Chicken Egg Description of Each Part Shell The hard coating of an egg, made of calcium carbonate. Gas can exchange but nothing else can enter. Inner and Outer Membrane Outer – shell is built around this and prevents dirt and bacteria from entering. Inner – Surrounds the white and the yolk. Air Sac Empty space located at the large end of the egg; the larger the air sac, the older the egg. Albumen The white part of an egg. There is no fat in the white. Germinal Spot/Disc A white spot on the yolk. This is where the sperm enter the egg and contains the egg’s DNA. “Nucleus” Yolk Contains all the fat and cholesterol of an egg and essential nutrients. Chalaza Twisted strands of fibers. Holds the yolk in the center of the egg. 13 Parts of an Egg How well do you know the parts of an egg? Test your knowledge: Parts of an Egg Board Activity 14 Parts of an Egg GROUP ACTIVITY: Carefully break a raw egg into a custard cup or bowl. Inspect the yolk and white and feel both with your fingers. Answer the questions on the study sheet provided. 15