Unit 9: Nervous System

Multiple Sclerosis (MS)

An autoimmune disease characterized by the demyelination of neurons in the nervous system.

Demyelination

The loss of myelin sheath from around the nerve fibers, leading to impaired signal transmission.

Neurologist

A medical doctor specializing in the diagnosis and treatment of nervous system disorders.

MRI (Magnetic Resonance Imaging)

A non-invasive imaging technology used to visualize internal structures of the body, particularly useful for brain scans.

Lumbar puncture (spinal tap)

A medical procedure where a needle is inserted into the spinal canal to collect cerebrospinal fluid.

Lesions

Areas of tissue that have been damaged or altered due to disease, often seen in brain scans.

Neurologial symptoms of MS

Include sensory loss, vision problems, muscle cramps, and cognitive difficulties.

Neurons

The functional units of the nervous system responsible for transmitting information.

Myelin sheath

A protective covering that insulates axons and facilitates faster transmission of nerve impulses.

Nodes of Ranvier

Gaps in the myelin sheath that enable rapid conduction of nerve impulses.

CNS (Central Nervous System)

The part of the nervous system consisting of the brain and spinal cord.

PNS (Peripheral Nervous System)

Nerves that connect the central nervous system to the rest of the body.

Somatic Nervous System

The division of the peripheral nervous system that controls voluntary muscles.

Autonomic Nervous System

Controls involuntary bodily functions such as heartbeat and digestion.

Parasympathetic Nervous System

The part of the autonomic nervous system responsible for rest and digest functions.

Sympathetic Nervous System

The part of the autonomic nervous system responsible for the fight or flight response.

Neuroglial Cells

Cells that provide support and protection for neurons.

Astrocytes

Neuroglia that support neurons by providing nutrients and maintaining the blood-brain barrier.

Oligodendrocytes

Cells in the CNS that produce myelin for axons.

Microglial Cells

Immune cells of the central nervous system that remove debris and pathogens.

Synapse

The junction between two neurons where neurotransmitters are released and received.

Neurotransmitter

Chemical messengers that transmit signals across a synapse from one neuron to another.

Excitatory neurotransmitters

Substances that enhance the likelihood of a neuron firing an action potential.

Inhibitory neurotransmitters

Substances that decrease the likelihood of a neuron firing an action potential.

Acetylcholine

A neurotransmitter involved in muscle activation and memory.

Dopamine

A neurotransmitter associated with mood, pleasure, and reward.

Serotonin

A neurotransmitter that helps regulate mood, sleep, and appetite.

Endorphins

Neurotransmitters that act to reduce pain and promote feelings of pleasure.

Antagonist

A molecule that blocks or inhibits the action of a neurotransmitter.

Agonist

A molecule that mimics the effect of a neurotransmitter on the postsynaptic neuron.

Epilepsy

A neurological disorder characterized by epileptic seizures due to excessive electrical activity in the brain.

Meningitis

An inflammation of the protective membranes covering the brain and spinal cord, typically due to infection.

Cerebrospinal Fluid (CSF)

A clear liquid that surrounds and cushions the brain and spinal cord.

Cerebrum

The largest part of the brain responsible for higher mental functions such as thought and action.

Cerebellum

Part of the brain that regulates balance and coordination.

Brain Stem

Part of the brain that controls basic life functions such as breathing and heartbeat.

Hippocampus

A brain structure involved in the formation of memories.

Amygdala

A brain structure involved in emotion regulation and fear response.

Ventricles

Fluid-filled cavities in the brain that contain cerebrospinal fluid.

Thalamus

A relay station for sensory and motor signals in the brain.

Hypothalamus

A brain region controlling hormones, temperature, and other autonomic processes.

Pituitary Gland

The master gland of the endocrine system, regulating various hormones and bodily functions.

Action Potential

A rapid change in electrical potential across a neuron's membrane that allows the nerve impulse to travel.

Depolarization

The process during the action potential when the inside of the neuron becomes more positive relative to the outside.

Repolarization

The return of the membrane potential to its resting state after depolarization.