Understanding the Nervous System Quiz

Study Notes

Nervous System

The nervous system is a complex network of cells, fibers, and structures that transmit information between different parts of the body. It is responsible for generating and sending electrochemical signals throughout the body. The nervous system consists of two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS).

Central Nervous System (CNS)

The CNS is made up of the brain and spinal cord. It controls thought, movement, and emotion, as well as breathing, heart rate, hormones, and body temperature. The brain is the most complex organ in the body and uses about 20% of the total oxygen we breathe. It consists of an estimated 100 billion neurons, which are connected to thousands more.

Brain

The brain can be divided into four main lobes: temporal, parietal, occipital, and frontal. It is protected by the skull (the cranial cavity) and is housed within a protective triple-layered membrane called the meninges.

Spinal Cord

The spinal cord runs from the back of the brain, down the center of the spine, stopping in the lumbar region of the lower back. It is responsible for transmitting sensory information to the brain and motor commands from the brain to the rest of the body.

Peripheral Nervous System (PNS)

The PNS includes all of the nerves that branch out from the spinal cord to different parts of the body. It is made up of two main types of nerves: sensory nerves, which transmit information from the body to the brain, and motor nerves, which transmit information from the brain to the body.

Nervous System Disorders

Common problems of the nervous system include epilepsy, meningitis, multiple sclerosis, Parkinson's disease, sciatica, shingles, and stroke.

Nervous System Structure and Function

The nervous system uses tiny cells called neurons to send messages back and forth from the brain, through the spinal cord, to the nerves throughout the body. Billions of neurons work together to create a communication network. Different neurons have different jobs, such as sensory neurons that send information from the eyes, ears, nose, tongue, and skin to the brain, and motor neurons that carry messages away from the brain to the rest of the body to allow muscles to move.

Neurons consist of a cell body and various extensions called dendrites and axons. Dendrites act like antennae, receiving signals from other neurons and passing them on to the cell body. The signals are then passed on via the axon, which can be up to a meter long. The nervous system has two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS).

Central Nervous System (CNS)

The CNS includes the nerves in the brain and spinal cord. It is safely contained within the skull and vertebral canal of the spine.

Voluntary Nervous System (Somatic Nervous System)

The somatic nervous system controls all the things that we are aware of and can consciously influence, such as moving our arms, legs, and other parts of the body.

Involuntary Nervous System (Autonomic Nervous System)

The autonomic nervous system regulates processes in the body that we cannot consciously influence, such as breathing, heartbeat, and metabolic processes. It is constantly active and can react quickly to changes, altering processes in the body to adapt.

Peripheral Nervous System (PNS)

The PNS includes all of the nerves outside of the CNS. It is further divided into the somatic nervous system, which controls voluntary movements, and the autonomic nervous system, which controls involuntary functions.

Involuntary Nervous System (Autonomic Nervous System)

The autonomic nervous system is further divided into the sympathetic and parasympathetic nervous systems. The sympathetic nervous system prepares the body for physical and mental activity, while the parasympathetic nervous system is responsible for bodily functions when we are at rest.

Enteric Nervous System (Gastrointestinal Nervous System)

The enteric nervous system is a separate nervous system for the bowel, which autonomously regulates bowel motility in digestion.

Nervous System Disorders

Some common problems of the nervous system include epilepsy, meningitis, multiple sclerosis, Parkinson's disease, sciatica, shingles, and stroke.

Conclusion

The nervous system plays a critical role in controlling and coordinating the functions of the body. It consists of the brain and spinal cord, which make up the central nervous system, and all other nerves, which make up the peripheral nervous system. The nervous system uses neurons to send messages and is responsible for generating and sending electrochemical signals throughout the body. It is divided into the somatic and autonomic nervous systems, which control voluntary and involuntary functions, respectively. Understanding the structure and function of the nervous system is essential for maintaining its health and preventing disorders.

Description

Test your knowledge about the structure and functions of the nervous system including the central nervous system, peripheral nervous system, neurons, and nervous system disorders. Learn about the divisions of the autonomic and somatic nervous systems.