Biology STAAR (State of Texas Assessments of Academic Readiness) Practice Test

What is the main function of the nervous system?

1. To produce hormones for bodily functions

2. To facilitate gas exchange in the body

3. To carry messages from the brain throughout the body

4. To support and protect internal organs

The correct answer is: To carry messages from the brain throughout the body

The main function of the nervous system is to carry messages from the brain throughout the body. This system is responsible for coordinating and controlling many bodily functions by transmitting signals that communicate information between different parts of the body. It enables the body to respond to stimuli, regulate bodily processes, and maintain homeostasis. The nervous system is composed of the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, which encompasses all the peripheral nerves. These structures work together to ensure that information is processed quickly and accurately, allowing for reactions to environmental changes and effective functioning of organs and systems within the body. In the context of the other functions listed, the production of hormones pertains to the endocrine system, which is primarily responsible for regulating physiological processes through chemical messengers. Gas exchange is a function of the respiratory system, where oxygen and carbon dioxide are exchanged in the lungs. Supporting and protecting internal organs is the role of the skeletal system and various connective tissues in the body. Thus, the nervous system's unique role in signal transmission distinguishes it from these other systems.