Nervous System Overview

The largest part of the brain, responsible for higher cognitive functions like thinking, memory, and language.

A group of structures deep within the brain involved in planning, movement, and coordination.

A structure in the brain involved in forming new memories.

The central relay station for sensory information.

A structure responsible for regulating body temperature, hunger, thirst, and sleep.

Part of the nervous system made of the brain and spinal cord.

Part of the nervous system that connects the CNS to the rest of the body.

The subdivision of the PNS responsible for voluntary control of skeletal muscles.

Sensory neurons carry sensory impulses from the periphery to the central nervous system (CNS). They act like messengers, bringing information about your senses, like touch, taste, and smell, to the brain and spinal cord.

Golgi Type I neurons have long axons that can reach remote peripheral organs. Imagine them as long-distance runners, connecting different parts of the nervous system.

Golgi Type II neurons have short axons that stay within the cerebral cortex or spinal cord. Think of them as local messengers, communicating within a specific area.

The nerve cell body, or soma, is the control center of a neuron. It contains the nucleus and other important components for the neuron's function.

Nissl bodies are small granules found in the cytoplasm of neurons. They synthesize proteins, which are essential for the neuron's function.

Dendrites are branched processes of a neuron that transmit impulses towards the nerve cell body. Think of them as receivers, gathering information from other neurons.

The axon is a long, thin process of a neuron that transmits impulses away from the nerve cell body. Think of it as a transmitter, sending information to other neurons or muscle cells.

The epineurium is a membrane that covers the entire nerve. It provides protection and support for the nerve fibers.

A type of nerve injury where the endoneurium is interrupted, but the epineurium and perineurium remain intact. Recovery is slow.

The process of degeneration that occurs in the axon of a nerve fiber distal to the injury site.

A process that occurs in the neuron cell body after an injury to its axon, leading to changes in the cell body.

A type of nerve injury where all coverings of the nerve are interrupted, leading to complete nerve damage.

A process of nerve regeneration where a new axon grows from the cell body to the site of injury.

The cytoplasm within the axon, containing structures like mitochondria, neurofibrils, and axoplasmic vesicles.

The membrane covering the axon, responsible for regulating what enters and exits the axon.

The process by which proteins synthesized in the cell body are transported along the axon.

The fatty sheath covering the axon, responsible for faster conduction of nerve impulses.

Gaps in the myelin sheath where the axolemma is exposed, allowing for saltatory conduction.

The segment of the axon between two Nodes of Ranvier, covered by myelin.

The process of forming the myelin sheath by Schwann cells, starting in the 4th month of fetal development.

A thin membrane surrounding the axon, containing Schwann cells with flattened nuclei, and essential for myelin sheath formation.

A protein that promotes the growth and survival of neurons, particularly in sympathetic and sensory neurons.

One of the subunits of NGF, responsible for its ability to stimulate nerve growth.

A protein found in the brain and sperm that promotes the survival of sensory and motor neurons.

A protein secreted by peripheral nerves, ocular muscles, and cardiac muscle that protects neurons in specific regions.

A protein found in neuroglial cells that protects dopaminergic neurons, critical for movement control.

A protein originally discovered for its role in promoting the growth of fibroblasts, but also known to protect neurons.

A protein that acts on various neurons, including motor neurons, and regulates neurotransmitter release.

A classification of nerve fibers based on their structural features, distribution, origin, and function.

Nerve fibers that release acetylcholine (ACh) as their neurotransmitter. They play a crucial role in various functions, including muscle contraction, heart rate regulation, and cognitive processes.

Nerve fibers that release noradrenaline (norepinephrine) as their neurotransmitter. They are involved in regulating various physiological processes, such as heart rate, blood pressure, and stress response.

The thickest type of nerve fiber, classified into subtypes based on their speed and function. These fibers are responsible for transmitting rapid and precise signals, including those involved in muscle contraction and sensory perception.

Thinner than Type A fibers, these myelinated nerve fibers transmit signals at a moderate speed. They are involved in various functions, including sensory perception, pain transmission, and autonomic regulation.

The thinnest and unmyelinated nerve fibers, transmitting signals at the slowest speed. They are responsible for carrying pain sensations, temperature signals, and autonomic functions.

The ability of a nerve fiber to respond to a stimulus by generating an action potential. It is a fundamental property of nerve cells, allowing them to communicate with each other and the rest of the body.

The rapid depolarization and repolarization of a nerve fiber membrane, creating a brief electrical signal that travels along the nerve. It is the primary way nerve cells communicate with each other and the rest of the body.

The period after an action potential during which the nerve cell is less likely to generate another action potential. This limits the rate of nerve impulse transmission.