Calories Application of energy

Combustion Reactions A chemical reaction that has oxygen as a reactant. Is this exothermic or endothermic?

Is cellular respiration a combustion reaction? How can we measure aerobic respiration?

How else can we measure it? Energy: the capacity to do work Calorie: a unit that measures energy Heat energy required to raise the temperature of one gram of water by one degrees Celsius Calorie = kilocalorie : heat energy required to raise the temperature of one kilogram (1000 grams) by one degrees of Celsius

Food Items that “ have Calories ” Carbohydrates - provide energy (4 cal/gram) Fats & Oils - provide energy (9 cal/ gram) Proteins - provide energy (4 cal/ gram) Vitamins- CANNOT provide energy Minerals- CANNOT provide energy Water- CANNOT provide energy

Energy Provided by Food Carbohydrates - provide energy (4 cal/gram) Fats - provide energy (9 cal/ gram) Proteins - provide energy (4 cal/ gram) Calorie: energy required to raise 1g of water 1 o C Which has the most calories per serving?

Calorimetry Lab. NO TOLERANCE POLICY 1.Did you write down the mass of food and crucible? 2.Did you write down the initial temperature of water? Now you are ready to burn food. 1.Did you dump out the water, empty food remnants and clean off can and crucible? 2.Proceed back to step 1.

Food usage in your body Food “has calories” ie. food has energy Bonds are broken from carbohydrates, fats/ oils and proteins. “doing nothing” requires energy- to breathe, pump blood, blink, swallow, etc. “doing nothing” = resting metabolic rate Technically basal metabolic rate

Metabolic Rates Basal Metabolic Rate = “doing nothing” Resting Metabolic Rate = your body is constantly building things and breaking down things Both REQUIRE ENERGY (ATP) What does this have to do with weight gain and loss?

Weight Gain Eat more, exercise less More Calories and less exercise = use ______ ATP to maintain daily activities Body is working less hard so will store excess energy as starch (glycogen) or fat to make ATP later when needed Loss Eat less, exercise more Less Calories and more exercise = ______ ATP to maintain daily activities Body is working harder so will use need more energy and will use starch storage and perhaps fat to convert to ATP

Summarize past two Weeks

Questions on Calorie WS/ Lab