explain how muscles and organs get energy
Answers
explain how muscles and organs get energy by eating food.
The first law of thermodynamics states that energy cannot be created, but must be transferred or converted from one form to another. Like an automobile only runs on gasoline, the human body runs on only one kind of energy: chemical energy. More specifically, the body can use only one specific form of chemical energy, or fuel, to do biological work – adenosine triphosphate (ATP).
ATP – the gas in the tank
So, how does the human body make ATP, the only fuel it can convert to energy? Our bodies have three different chemical systems that convert energy. Most everyone knows that we use proteins, carbohydrates and fats for energy. Calories are measurement of a unit of heat or food energy. For example, we can achieve four calories per gram of proteins and carbohydrates, and nine calories per gram from fats.
But how do we convert these potential energy substances into ATP? This is where three energy systems come into play.
Energy System 1: Ready fuel for immediate energy
The Immediate Energy system, or ATP-PC, is the system the body uses to generate immediate energy. The energy source, phosphocreatine (PC), is stored within the tissues of the body. When exercise is done and energy is expended, PC is used to replenish ATP. Basically, the PC functions like a reserve to help rebuild ATP in an almost instantaneous manner.
So, in the quadriceps and hamstring muscle groups of an average athlete, a specific quantity of ATP and PC stored within the muscle. These stored substrates are ready and waiting to be chemically transformed to fuel biological work process – such as contracting a muscle. This system gives athletes a readily available store of energy which can be accessed without delay.
What’s the downside?
The average athlete will have approximately 285 grams of stored ATP in his or her entire body. That amount of ATP will be consumed in a just few seconds of work. At any time, athletes have only about 10 seconds worth of ATP-PC.
A supplement called creatine monohydrate that can increase the amount of PC stored in the muscles. It is one of the most researched ergogenic aids available and it does work. However, it can cause muscle cramps and it is not recommended for use during hot weather.
Energy System 2: Glucose-fueled quick energy
The glycolytic system, sometimes called anaerobic glycolysis, is a series of ten enzyme-controlled reactions that utilize carbohydrates to produce ATP and pyruvate as end products.
Glycolysis is the breakdown of glucose. Technically, glycolysis can use glucose or glycogen in its chemical reactions. The glucose must enter the cell membrane to begin the process. Upon entering the cell, the glucose will begin a transformation that will produce a net of two ATP and two pyruvate molecules. These 10 reactions occur very rapidly. Glycolysis is the preferred energy system by the human body when any sort of exercise work is required. The process is fast, there is generally plenty of glucose available and the reactions can occur anywhere within the cell’s sarcoplasm.