Living systems rely on their environment for survival, and the evolution of environmental adaptation is closely linked to the evolution of life itself. Environmental adaptation in animals and humans also includes adaptive behavior. In this article, we will be focusing on neurons and nervous system and their impact on brain structure and function as well as behavior.
The nervous system processes and transmits information throughout the body. It instructs the body on how to respond to stimuli, such as controlling the body temperature when environment changes. It is also responsible for reflex actions; they are quick and automatic action that does not involve the brain, this function protects the body from harm, such as quickly react when touching a hot surface, sneezing, and blinking the eye. In humans and other vertebrates, the nervous system can be broadly divided into two sections: the central nervous system and the peripheral nervous system. The brain and spinal cord make up the central nervous system (CNS), this is where all information analysis happens. On the other hand, the peripheral nervous system (PNS) is made up of all the neurons and sections of neutrons that are located outside of the central nervous system.
Neurons are the primary nerve cells of the body, they are specialized to carry electrical impulses form one place to another, and a bundle of neurons is called a nerve. Each neuron features a long axon, so they can carry messages up and down the body. When stimulated, neurons generate electrical nerve impulses that travel along the axon. Both sensory and motor neurons are a part of the PNS. Sensory neurons gather information from the body’s internal and external environments and transfer it to the central nervous system for processing. For example, sensory neurons in your fingertips would alert your central nervous system if you touched on a hot surface. The motor neurons are responsible for sending messages from the central nervous system to the sensory neurons. The basic functions of a neuron are receiving signals; integrate incoming signals; communicate signals to target cells.
Neurons are connected by interneurons, which are found only in the CNS. Both sensory and interneuron neurons can send information to and receive information from these other neurons. For instance, if you touched a hot surface, the signal from the sensory neurons in your fingertips would travel to interneurons in our spinal cord. While some of these interneurons would send a signal up the spinal cord to neurons in the brain, where it would be interpreted as pain, others would send a signal to the motor neurons controlling your finger muscles, forcing you to release your hand from the hot surface.
The nervous system provides the foundation for how organisms interact with and adjust to their surroundings. It guides the body’s reactions to stimuli like temperature changes and helps the body process and transmit information throughout. This complex network of neurons and nerve pathways supports adaptive behaviors that are crucial for survival in a changing environment.
Reference:
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Rudge, P. , Loewy, . Arthur D. , Nathan, . Peter W. , Matthews, . Peter B.C. , Ratcliff, . Graham , Haines, . Duane E. , Lentz, . Thomas L. and Noback, . Charles R. (2024, April 22). human nervous system. Encyclopedia Britannica. https://www.britannica.com/science/human-nervous-system
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