Physiology_Lecture_Outline/md6

Meninges

Three layers of protective tissue that cover the brain and spinal cord.

Dura Mater

The tough outer layer of the meninges that provides a strong protective barrier.

Arachnoid Mater

The middle layer of the meninges with a web-like structure, helping to cushion the brain.

Pia Mater

The thin inner layer of the meninges that adheres tightly to the brain and spinal cord.

Cerebrospinal Fluid (CSF)

Fluid that circulates around the brain and spinal cord, providing protection and nourishment.

White Matter

Made up of bundles of nerve fibers (axons) covered in myelin, responsible for signal transmission.

Gray Matter

Contains the cell bodies of neurons; involved in processing information and higher brain functions.

Axons

Long nerve fibers that transmit electrical signals between neurons.

Myelin

A fatty substance that covers axons, speeding up electrical signal transmission.

Action Potential

An electrical signal that travels along nerve fibers, crucial for communication within the nervous system.

Depolarization

The process of making the membrane potential of a neuron more positive during an action potential.

Repolarization

The process of returning the membrane potential to a negative value after depolarization.

Hyperpolarization

A phase where the membrane potential temporarily becomes more negative than the resting potential.

Resting Membrane Potential

The stable voltage of a neuron at rest, typically around -70 mV.

Sympathetic Nervous System

Part of the autonomic nervous system that prepares the body for 'fight or flight' responses.

Parasympathetic Nervous System

The division of the autonomic nervous system responsible for 'rest and digest' activities.

Thalamus

Acts as the brain’s relay station, directing sensory information to appropriate areas.

Cerebellum

Responsible for coordination and balance of voluntary movements.

Medulla

Regulates vital life functions, including heart rate, blood pressure, and breathing.

Pons

Connects different parts of the brain and regulates sleep cycles and breathing.

Olfaction

The sense of smell, involving detection of chemical molecules in the air.

Gustation

The sense of taste, involving detection of chemicals dissolved in food.

Taste Buds

Specialized structures on the tongue that contain gustatory cells for taste perception.

Neurotransmitters

Chemical messengers released by neurons to communicate with other cells.

Ligand-gated Ion Channels

Ion channels that open in response to binding of a specific chemical messenger.

Synaptic Clef

The space between the presynaptic and postsynaptic neurons where neurotransmitters are released.

Skeletal Muscle

Muscle under voluntary control that allows for movement of the body.

Reflex Arc

The neural pathway that mediates a reaction to a stimulus without involving the brain.

Ion Channels

Proteins that allow ions to flow into or out of the cell, crucial for action potentials.

Epidural Space

The area between the dura mater and the walls of the vertebral canal, significant for anesthesia.

Subarachnoid Space

Region between the arachnoid mater and pia mater, containing CSF.