The liver and kidneys must work hard to use protein to meet energy needs because ____.Multiple choice question.carbohydrates are less available than protein as an energy sourceproteins require a lot of processing to produce energyproteins are more easily absorbed than carbohydrates

The liver and kidneys must work hard to use protein to meet energy needs because proteins require a lot of processing to produce energy.

Here's why:

1. Proteins are complex molecules: Proteins are made up of amino acids and are more complex than carbohydrates. This complexity means that the body needs to work harder to break them down into usable components.

2. Deamination process: Before proteins can be used for energy, they must undergo a process called deamination. This process occurs primarily in the liver and involves removing the amino group from the amino acid. This process requires energy and produces ammonia, a toxic byproduct that the kidneys must filter out and excrete from the body.

3. Energy production: Once deamination has occurred, the remaining components of the protein can enter the Krebs cycle (also known as the citric acid cycle or TCA cycle) for energy production. This process also requires several steps and thus, more energy.

So, while proteins can be used as an energy source, they require more processing by the liver and kidneys compared to carbohydrates, making it a more energy-intensive process.