International Sports Sciences Association (ISSA) Trainer Practice Exam

Which of the following describes a major function of peptides?

1. Energy production

2. Oxygen transport

3. Cell signaling

4. Muscle contraction

The correct answer is: Cell signaling

Peptides play a significant role in cell signaling, which is crucial for various biological processes. They are short chains of amino acids that can act as signaling molecules in the body. When released, peptides can interact with specific receptors on the surface of cells, triggering a response that can influence a wide range of functions, such as hormone regulation, immune responses, and neurotransmission. This cell signaling capacity is essential for maintaining homeostasis and enabling communication within and between different cells and tissues. For example, certain peptides known as neuropeptides influence brain function and mood, while others, like insulin, regulate glucose metabolism. The ability of peptides to serve as messengers in the body underlines their importance in health and disease, highlighting why cell signaling is considered a major function of peptides.