The functions of organs and organ systems in our body must be coordinated to maintain homeostasis. Coordination involves the interaction and complementary functioning of two or more organs. For example, during physical exercises, there is an increased demand for energy to support heightened muscular activity. This requires an increased supply of oxygen, which in turn necessitates a higher rate of respiration, increased heartbeat, and enhanced blood flow through blood vessels. When the physical exercise stops, the activities of the nerves, lungs, heart, and kidneys gradually return to their normal states. Thus, during physical exercises, the functions of muscles, lungs, heart, blood vessels, kidneys, and other organs are coordinated.

In our body, the neural system and the endocrine system jointly coordinate and integrate the activities of all organs to ensure synchronized functioning. The neural system provides a network of point-to-point connections for quick coordination, while the endocrine system ensures chemical integration through hormones. This chapter focuses on the neural system of humans and mechanisms of neural coordination, such as nerve impulse transmission and impulse conduction across a synapse.

Overview

The neural system of animals consists of highly specialized cells called neurons, which can detect, receive, and transmit different kinds of stimuli. The complexity of the neural organization varies across species:

1.Lower Invertebrates: In organisms like Hydra, the neural system is composed of a simple network of neurons.

2.Insects: The neural system is more organized, featuring a brain along with several ganglia and neural tissues.

3.Vertebrates: The neural system is highly developed and complex.