Contextualization
The energy that fuels our bodies and allows us to do everything from running to thinking comes from the food we eat. This energy-rich food comes in the form of carbohydrates, proteins, and fats, and is broken down through a process called digestion. The energy released is then stored as a molecule called ATP (adenosine triphosphate), which is used by our cells as a source of energy.
However, the energy stored in food isn't a form that our bodies can directly use. It must be converted into ATP through a series of biochemical reactions. This process is called cellular respiration, and it occurs in the mitochondria of our cells.
Animals, including humans, are heterotrophs, which means they must consume other organisms or their by-products to get the energy they need. This energy is transferred through a food chain or food web from producers (plants) to consumers (animals) and then to decomposers (bacteria and fungi).
Understanding the process of energy transfer in animals is crucial for understanding how ecosystems function. It allows us to understand how energy flows from the sun, through plants, to herbivores, carnivores, and decomposers. It also helps us understand how changes in one part of the food web can affect other parts.
Introduction
The energy in our food is ultimately derived from the sun. It is captured by plants through a process called photosynthesis, where they use sunlight, carbon dioxide, and water to produce glucose and oxygen. This glucose is used by plants to provide energy for growth and reproduction.
When animals eat plants, they consume this stored energy. Some of the energy is used by the animal to power its own body functions, and some is stored as fat or used for growth and reproduction. When animals eat other animals, they are getting the energy that those animals obtained by eating plants.
This transfer of energy from one organism to another is never 100% efficient. Some energy is always lost as heat, and some is used by the organism for things like movement and digestion. This is why there are typically fewer top predators in an ecosystem than there are herbivores. There simply isn't enough energy available to support large numbers of top predators.
