* Glycogen: This is the primary storage form of carbohydrates in animals. It is a branched polymer of glucose that is stored mainly in the liver and muscles. When the body needs energy, glycogen is broken down into glucose, which can be used by cells for energy production.
* Fat (triglycerides): This is the primary storage form of energy in animals. Fat is stored in specialized cells called adipocytes. When the body needs energy, fat is broken down into fatty acids and glycerol, which can be used by cells for energy production.
* Proteins: While proteins are primarily used for building and repairing tissues, they can also be used as an energy source in times of need. They are stored in the muscles and other tissues. When the body needs energy from protein, it breaks down the protein into amino acids, which can be used by cells for energy production.
Here's a breakdown by animal type:
* Mammals: Primarily store energy as glycogen and fat.
* Birds: Store energy as fat, particularly in the form of subcutaneous fat (beneath the skin).
* Fish: Store energy as fat in their liver and muscles.
* Insects: Store energy as glycogen and fat, sometimes in specialized structures like fat bodies.
It's important to note that the specific form and location of food storage can vary widely between different species.