Metabolism breaks down large molecules like food into usable energy. This energy drives bodily processes critical to survival. In this video lesson, you will learn about the two forms of metabolism that break down and build up molecules and see examples of each.
Metabolism in Your Body
Have you ever wondered what happens to the food that you eat after it enters your body? As you probably know, food not only tastes good, but it also provides nutrition for all of the different components of your body - bones, muscles, brain function, and much more!
A salad is chock full of nutritious goodies, but your body can't do much with the food as it is. So as food enters your body, it gets broken down into molecular components so that you can actually use the nutrition these molecules provide. All of the physical and chemical activities in your body that convert or use energy are called metabolism. These include things like breathing, digesting food, and circulating blood.
But metabolism is a pretty broad term, and it includes all of the chemical activities in your body. We can think of metabolism in two separate forms: catabolism and anabolism. Catabolism involves all of the metabolic processes that tear down biomolecules, while anabolism is all of the metabolic processes that build biomolecules.
One way to remember which is which is to think of 'catastrophe' for catabolism and 'steroids' for anabolism. During a catastrophe like an earthquake, large buildings and other structures fall apart, just like molecules get broken apart during catabolic reactions. People use anabolic steroids to build up their muscles, just like anabolic reactions 'build' biomolecules.
Catabolism Breaks Down Molecules
Catabolic reactions are reactions that involve the breakdown of biomolecules, but what exactly does this mean? When you eat food, you chew it to make it easier to swallow, right? Catabolic reactions are similar in that they 'chew' up biomolecules to make them easier to utilize.
Digestion is a catabolic activity. Here, you begin with large food molecules, and then water is used to break the bonds in those molecules. These smaller molecules are then sent off to the cells in your body to participate in cellular respiration, which is a process that converts biochemical energy to ATP, a very high-energy molecule.
Cellular respiration is also a catabolic process because it breaks the small molecules from digestion into even smaller ones as ATP is created. These are both very important processes, because ATP is what your cells use to produce body heat, move your muscles, and other essential bodily functions.
Anabolism Builds Molecules
ATP not only provides energy to your cells, it also allows anabolic processes to occur. Anabolism is the reverse of catabolism, since these reactions build large biomolecules from smaller ones. And the molecules that are produced are the same types as what you find in food, such as carbohydrates and proteins. In a sense, these molecules are like your body's own version of the food it originally came from.
When your body builds muscle tissue, creates new cells, or mineralizes bone, these are all anabolic activities. They take smaller molecules that were broken down during catabolism and use them to build new, stronger material in your body.
These two forms of metabolism work together to create a balance in your body. In healthy muscle tissue, muscle breakdown (catabolism) is equal to muscle building (anabolism). But if you were to start exercising and eating more, anabolic reactions would be more prevalent as your body builds muscle mass. However, if you stop eating and exercising, the catabolic reactions take over as your muscle mass (and you!) begin to waste away.
Metabolism refers to all of the physical and chemical activities in your body that convert or use energy. These processes are what keep you alive and healthy and work together to keep an internal balance.
Catabolism involves all of the metabolic processes that break down biomolecules. These are activities like digestion and cellular respiration. The reverse of catabolism is anabolism, which involves all of the metabolic processes that build biomolecules. Anabolic processes allow your body to do things like build muscle mass, mineralize bone, and create new cells.
Molecules that are built during anabolic reactions are similar to the molecules you take in as food. In fact, if you become food for something else, its body will use catabolism to break down your biomolecules into small, usable ones and then build larger biomolecules through anabolism. You can see how these two metabolic processes simply recycle energy and nutrients through different organisms, allowing them to break down and build up the specific biomolecules they need to survive.
You should have the ability to do the following after this lesson:
- Define metabolism
- Summarize the role of ATP in metabolism
- Differentiate between catabolism and anabolism
- Identify examples of catabolism and anabolism