Physiology Review

Olfactory nerve (1)

sense of SMELL

Optic nerve (2)

transmitting VISUAL information

Oculomotor nerve (3)

moves the eyeball

Trochlear nerve (4)

innervates the eyelid muscle

Trigeminal nerve (5)

main sensory nerve of the face

Abducens nerve (6)

controls the lateral rectus muscle

Facial nerve (7)

innervates the muscles of facial expression

Vestibulocochlear nerve (8)

hearing and balance

Glossopharyngeal nerve (9)

swallowing, speech, and saliva

Vagus nerve (10)

innervates thoracic and abdominal organs

Accessory nerve (11)

innervates the shoulder muscles

Hypoglossal nerve (12)

supplies the tongue and is important for chewing and speech

Soma/cell body

The part of the neuron that interprets the signal

Nucleus

Stores the genetic material and is the “brain” of the neuron

Axon Hillock

Connects the axon to the cell body

Axon

Sends signals through neurotransmitters

Myelin Sheath

An insulating layer around nerves that is made up of lipids and fats, these conduct impulses faster than axons without it

Dendrites

The part of the neuron that receives a signal

Terminals

They are located at the end of the axon

Nodes of Ranvier

The gaps in between the myelin sheaths

Role of Na+

The ion that rushes into the cell, making it more positive (depolarization)

Role of K+

The ion that flows out during repolarization in attempt to rebalance the charges

Role of Na/K pump

Maintains the resting potential

Role of ATP

The energy used to rebalance the ions (resting potential) and is the energy needed to start the Na/K pump

Polarization

No ions move through voltage-gated channels (1)

Depolarization

The stage at which the mV of a neuron is increasing because Na+ is flowing into the cell (2)

Repolarization

The stage at which the mV of a neuron is decreasing because K+ is flowing out of the cell (3)

Hyperpolarization

Caused by K+ continuing to leave the cell, eventually bringing it back to its resting state(4)

Somatic

Voluntary branch of the nervous system

Autonomic

Involuntary branch of the nervous system

Sympathetic

Fight or flight response

Parasympathetic

Rest and digest response

Afferent

Nerves that travel from PNS to CNS

Efferent

Transmits from CNS out to the rest of the body

Central Nervous System

Brain and Spinal Cord/Column

Peripheral Nervous System

Cranial Nerves and Spinal Nerves

Oligodendrocytes produce

MULTIPLE myelin sheaths in the CNS

Schwann Cells produce

ONE myelin sheath in the PNS

Brain Stem

Responsible for basic life support

Cerebrum

Controls higher brain functions, including sensory perception, storing memory, reasoning, and determining intelligence

Frontal Lobe

Responsible for conscious, voluntary thought and attention, processing and making decisions, personality and language (primary motor cortex)

Parietal Lobe

The part of the brain that processes hearing and touch and relays it to the frontal lobe (primary sensory cortex)

Temporal Lobe

The part of the brain that stores memory and processes emotion

Occipital Lobe

The part of the brain that processes vision

Hippocampus

Holds our short-term memory (AKA brain’s librarian)

Cerebellum

The coordination center of the brain that is responsible for controlling movement and posture

Corpus Callosum

The part of the brain that connects the two hemispheres

Thalamus

The brain’s “relay station” where most information from the outside world passes through

Hypothalamus

The part of the brain that controls the endocrine system

Epithalamus

Forms the pineal gland which secretes melatonin, and regulates the day/night cycle

Amygdala

The part of the brain that processes stress and fear (primitive survival response center of the brain)

Ventricles

Cavities in the brain that are filled with cerebrospinal fluid

Meninges

Outer membranes surrounding the brain

Dorsal Root Ganglion

How impulses from receptors in the PNS and relayed to the spinal cord (this also contains unipolar cell bodies of sensory neurons)

Reflex arc

The nerve pathway which makes a rapid, autonomic response to a stimulus possible

Receptor

Receives stimulation which sends an impulse (in the PNS)

Sensory Nerve

Afferent impulses travel up this to the spinal cord

Interneuron

They send efferent impulses down motor neurons to the effector muscles which causes an action to occur

Motor Nerve

Nerves that control muscle movement

Effector

The muscles/organs that respond to the information received by sensory reception

Dura mater

Thick outer layer that adheres to the inside of the skull

Arachnoid mater

Web-like middle layer spanning fissures of brain; arteries and veins run on top of it

Pia mater

The meninge that is microscopic

Resting membrane potential

\-70 mV

Threshold potential

\-55 mV