Calories

How much energy is lost, and how is done?

60% of our energy is lost as heat. We produce as much heat as 75-watt bulb, but we aren't scorching to the touch bc our lost energy is spread throughout our body surface.

Calorie vs calorie?

A calorie raises the temp of gram of water by 1 degree Celsius. A Calorie, aka kilocalorie or 1000 calories. This raises temp of 1000 grams of water by 1 degree C (or theoretically 1 gram by 1000 degree C).

What molecule do we use to directly power metabolism?

ATP, hydrolysis of a mole of ATP molecule releases about 7 Calories of energy

What are the different types of food?

Fat: 9 Calories per gram. Protein: 4 Calories per gram. Carbs: 4 Calories per gram. Alcohol: 7 Calories per gram. This can be a big factor in over-eating. Let's say you are an average Joe who doesn't really know their nutrition facts. Because some foods are more calorie dense than others, like chicken wing vs celery, for the same volume of food, he would be eating more chicken wings than celery sticks in order to be full.

What if we eat more than we need?

It is stored as GLYCOGEN or FAT. As glycogen (polysaccharide), the excess energy is put into glycogen form and stored into the liver/muscle for quick access. One day's worth of energy is usually in store as glycogen. As fat, 0.3kg of fat with supply a day of energy, so most people(in first world countries) can last for weeks without food.

What is the basal metabolic rate?

This is the minimum number of kcals you need to consume while at rest in order to fuel all essential process for a given amount of time.

What is the metabolic rate?

This is the rate of energy consumption by an animal, so the sum of all the energy used by biochemical reactions over a period of time. This depends a lot on activity level.

What is the significance of Calories?

Well, for energy.