Which macromolecule is the primary source of long-term energy storage?

Prepare for the Virginia HESI Level 4 Test with an array of study materials including flashcards and multiple choice questions. Each question comes with hints and detailed explanations to assist in your exam preparation. Get set to ace your test!

Multiple Choice

Which macromolecule is the primary source of long-term energy storage?

Explanation:
Lipids provide the body's longest-lasting energy reserve. They pack about 9 kilocalories per gram, more than twice the energy per gram of carbohydrates, which give around 4 kcal/g. Because lipids are stored as triglycerides in adipose tissue with little associated water, they store energy very densely by weight, whereas carbohydrate stores (as glycogen) are hydrated and bulky. When energy is needed, triglycerides are mobilized, fatty acids are released and oxidized to generate ATP for extended periods, such as fasting or sustained activity. Proteins can be used for energy but are mainly for tissue maintenance, and nucleic acids store genetic information rather than energy. So lipids are the primary source of long-term energy storage.

Lipids provide the body's longest-lasting energy reserve. They pack about 9 kilocalories per gram, more than twice the energy per gram of carbohydrates, which give around 4 kcal/g. Because lipids are stored as triglycerides in adipose tissue with little associated water, they store energy very densely by weight, whereas carbohydrate stores (as glycogen) are hydrated and bulky. When energy is needed, triglycerides are mobilized, fatty acids are released and oxidized to generate ATP for extended periods, such as fasting or sustained activity. Proteins can be used for energy but are mainly for tissue maintenance, and nucleic acids store genetic information rather than energy. So lipids are the primary source of long-term energy storage.

Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy