(11) Anatomy and physiology 1 final review

Autonomic Neural System

Autonomic Neural System

The part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes.

Sympathetic Branch

The part of the autonomic nervous system that increases heart rate, dilates bronchi, and slows digestion.

Parasympathetic Branch

The part of the autonomic nervous system that slows the heart rate and increases intestinal and gland activity.

CNS vs PNS

CNS is the central nervous system (brain and spinal cord) while PNS is the peripheral nervous system (nerves outside the CNS).

Thoracolumbar Outflow

The outflow of sympathetic nerves that arise from the thoracic and lumbar regions of the spinal cord.

Craniosacral Outflow

The outflow of parasympathetic nerves that originate in the brain stem and sacral spinal cord.

Resting Membrane Potential (RMP)

The electrical potential difference across the neuron membrane at rest, typically around -70 mV.

Depolarization

A reduction in the membrane potential difference, making it more positive.

Repolarization

The process of returning the membrane potential back to the resting state after depolarization.

Hyperpolarization

An increase in membrane potential, making the interior of the cell more negative than the resting potential.

Continuous Conduction

A type of nerve impulse conduction in unmyelinated neurons where the impulse travels along the entire length of the axon.

Saltatory Conduction

A type of nerve impulse conduction in myelinated neurons where the impulse jumps from one Node of Ranvier to another.

EPSP (Excitatory Postsynaptic Potential)

A postsynaptic potential that makes the neuron more likely to fire an action potential.

IPSP (Inhibitory Postsynaptic Potential)

A postsynaptic potential that makes the neuron less likely to fire an action potential.

Neurotransmitter Removal

The process by which neurotransmitters are cleared from the synaptic cleft after transmitting a signal.

Acetylcholine

A neurotransmitter involved in muscle activation and many other functions.

GABA (Gamma-aminobutyric acid)

An inhibitory neurotransmitter that reduces neuronal excitability throughout the nervous system.

Glutamate

An excitatory neurotransmitter that plays a key role in synaptic plasticity and memory.

Cauda Equina

A bundle of spinal nerves and spinal nerve rootlets that resemble a horse's tail.

Reflex Arc

The neural pathway that mediates a reflex action, usually involving sensory neurons, interneurons, and motor neurons.

Dorsal Roots

The sensory roots of spinal nerves that carry sensory information into the CNS.

Ventral Roots

The motor roots of spinal nerves that carry motor commands to muscles.

Phrenic Nerve

A nerve that innervates the diaphragm, crucial for breathing.

Dermatome

An area of skin supplied by a single spinal nerve root.

Vagus Nerve

Cranial nerve that controls functions of the heart, lungs, and digestive tract.

Substantia Nigra

A brain structure involved in the regulation of movement and affected in Parkinson’s disease.

Broca's Area

A region in the frontal lobe linked to speech production.

Wernicke's Area

A region in the temporal lobe associated with language comprehension.

Aphasia

A disorder that affects communication abilities, caused by brain damage.

Ischemic Stroke

A type of stroke caused by a clot blocking blood flow to the brain.

Hemorrhagic Stroke

A type of stroke caused by bleeding in the brain.

Cerebrospinal Fluid Flow

The movement of CSF through the ventricles, subarachnoid space, and around the brain and spine.

Action Potential

A rapid rise and fall in voltage or membrane potential across a cellular membrane, typically associated with the propagation of a signal along nerve cells.

Threshold Potential

The critical level to which a membrane potential must be depolarized to initiate an action potential, usually around -55 mV.

All-or-None Law

The principle that an action potential either occurs fully or does not occur at all, depending on whether the threshold is reached.

Refractory Period

The time period during which a neuron is incapable of initiating another action potential, allowing for directional flow of impulse.

Sodium Channels

Membrane proteins that allow sodium ions to enter the neuron, playing a key role during the depolarization phase of an action potential.

Potassium Channels

Membrane proteins that allow potassium ions to exit the neuron, contributing to repolarization after an action potential.

Propagation of Action Potential

The process of action potentials traveling along the axon to transmit signals from the neuron to other cells.

Node of Ranvier

Gaps in the myelin sheath along the axon that facilitate rapid conduction of action potentials through saltatory conduction.

Myelination

The process of forming a myelin sheath around the axons of neurons, enhancing the speed of action potential propagation through saltatory conduction.

Calcium Channels

Channels that open in response to depolarization, allowing calcium ions to enter the neuron and facilitating neurotransmitter release.

Cerebrum

The largest part of the brain, responsible for higher brain functions including thought, action, and sensory processing.

Cerebellum

Located under the cerebrum, it is responsible for coordination and balance.

Brainstem

The part of the brain that connects the cerebrum to the spinal cord, controlling basic life functions such as heartbeat and breathing.

Medulla Oblongata

The lowest part of the brainstem, it regulates vital functions such as heart rate and respiration.

Thalamus

Located above the brainstem, it acts as a relay station for sensory and motor signals to the cerebral cortex.

Hypothalamus

A small region of the brain responsible for hormone production and regulation of many body functions, including temperature and hunger.

Spinal Cord

A long, thin bundle of nervous tissue that extends from the brainstem down the vertebral column, responsible for transmitting signals between the brain and body.

Dorsal Root

Nerve roots that carry sensory information to the spinal cord.

Ventral Root

Nerve roots that carry motor information away from the spinal cord.

Cauda Equina

A bundle of spinal nerves and nerve roots located in the lower part of the spinal canal.

Conus Medullaris

The tapered, lower end of the spinal cord, located at L1-L2 vertebral level.

Pia Mater

The delicate innermost layer of the meninges that directly covers the brain and spinal cord.

Arachnoid Mater

The middle layer of the meninges, located between the dura mater and pia mater.

Dura Mater

The tough outermost layer of the meninges, providing protection to the brain and spinal cord.

Cerebrospinal Fluid (CSF)

A clear fluid that surrounds the brain and spinal cord, providing cushioning and protection.

C5 Dermatome

Supplies sensation to the shoulder area and the lateral aspect of the arm.

C6 Dermatome

Supplies sensation to the lateral forearm and thumb.

C7 Dermatome

Supplies sensation to the middle finger and the posterior aspect of the arm.

C8 Dermatome

Supplies sensation to the ring finger and pinky finger, as well as the medial aspect of the forearm.

T1 Dermatome

Supplies sensation to the medial aspect of the arm and the axilla.

L1 Dermatome

Supplying sensation to the lower abdomen and groin.

L2 Dermatome

Supplies sensation to the upper thigh.

L3 Dermatome

Supplies sensation to the medial knee and the inner thigh.

L4 Dermatome

Supplies sensation to the medial ankle and foot.

L5 Dermatome

Supplies sensation to the lateral aspect of the leg and the dorsum of the foot.

S1 Dermatome

Supplies sensation to the posterior lateral part of the foot and the heel.

S2 Dermatome

Supplies sensation to the back of the thigh and part of the calf.

S3 Dermatome

Supplies sensation around the ischial tuberosity.

S4 Dermatome

Supplies sensation around the anal region.

Cranial Nerve I

Olfactory nerve; responsible for the sense of smell.

Cranial Nerve II

Optic nerve; responsible for vision.

Cranial Nerve III

Oculomotor nerve; controls most of the eye's movements, pupil constriction, and maintaining an open eyelid.

Cranial Nerve IV

Trochlear nerve; controls the superior oblique muscle of the eye, which is responsible for downward and lateral movement.

Cranial Nerve V

Trigeminal nerve; responsible for sensation in the face and motor functions such as biting and chewing.

Cranial Nerve VI

Abducens nerve; controls the lateral rectus muscle, responsible for moving the eye outward.

Cranial Nerve VII

Facial nerve; controls muscles of facial expression, and functions in the sense of taste and the regulation of glands.

Cranial Nerve VIII

Vestibulocochlear nerve; responsible for hearing and balance.

Cranial Nerve IX

Glossopharyngeal nerve; involved in taste, swallowing, and some functions of the salivary glands.

Cranial Nerve X

Vagus nerve; controls functions of the heart, lungs, and digestive tract.

Cranial Nerve XI

Accessory nerve; controls shoulder and neck muscles.

Cranial Nerve XII

Hypoglossal nerve; controls tongue movements.

EEG (Electroencephalogram)

A test used to detect abnormalities in the brain waves or electrical activity of the brain.

Delta Waves

Low-frequency brain waves (0.5-4 Hz) associated with deep sleep.

Theta Waves

Brain waves with a frequency of 4-8 Hz, commonly found in light sleep, relaxation, and during meditation.

Alpha Waves

Brain waves with a frequency of 8-12 Hz, associated with relaxed but alert states, often seen in wakeful resting.

Beta Waves

High-frequency brain waves (12-30 Hz) associated with active thinking, problem-solving, and focus.

Gamma Waves

Very high-frequency brain waves (above 30 Hz) associated with high-level cognitive functioning and information processing.

Importance of EEG

Used for diagnosing conditions such as epilepsy, sleep disorders, and measuring brain activity during different states.

Acetylcholine

An important neurotransmitter that plays a role in brain functions, such as memory, and body functions, such as muscle contractions.

GABA

Known for its calming effect and is thought to play a role in controlling anxiety, stress, and fear.

Glutamate

Stimulates nerve cells to send chemical messages; essential for learning, memory, and mood regulation.

Dopamine

Plays a role in many important body functions, including movement, memory, and pleasurable reward and motivation.

Serotonin

Regulates various activities, including behavior, mood, memory, and gastrointestinal homeostasis.

Norepinephrine

A neurotransmitter that plays an essential role in the regulation of arousal, attention, cognitive function, and stress reactions.

Epinephrine

A hormone and medication used to treat life-threatening allergic reactions and other medical emergencies.