exam 1

Sensory receptors

Cells that detect changes in the environment.

Myelin

Insulation around the axon that speeds up nerve conduction.

Oligodendrocytes

Glial cells in the CNS that produce myelin.

Schwann cells

Glial cells in the PNS that produce myelin.

Demyelinating disease

Conditions that damage the protective myelin coating on nerve cells.

Guillain-Barré syndrome (GBS)

A rare autoimmune disorder affecting peripheral nerves.

Multiple sclerosis (MS)

A chronic autoimmune disease that affects the CNS.

Ganglia

Clusters of neuron cell bodies in the PNS.

Nuclei

Clusters of neuron cell bodies in the CNS.

Autonomic Nervous System (ANS)

Regulates involuntary bodily processes.

Somatic Nervous System (SNS)

Controls voluntary movements and relays sensory information.

Synapse

A junction where neurons transmit impulses to each other.

Subthreshold stimulus

A stimulus that is not strong enough to trigger an action potential.

Excitatory postsynaptic potential (EPSP)

Membrane change that depolarizes a postsynaptic neuron.

Inhibitory postsynaptic potential (IPSP)

Membrane change that hyperpolarizes a postsynaptic neuron.

Resting Membrane Potential

Electrical charge across a membrane without ion movement.

Action potential

A rapid electrical signal generated by a neuron.

Repolarization

Return to resting potential after an action potential.

Depolarization

Change from negative to positive charge inside a cell.

Neurotransmitters

Chemicals that transmit signals across a synapse.

Meninges

Protective layers surrounding the brain and spinal cord.

Epidural hematoma

Blood collection between the skull and dura mater.

Subdural hematoma

Blood collection between the dura mater and brain surface.

Cerebrospinal fluid (CSF)

Fluid that cushions the brain and spinal cord.

Reflex arc

The pathway for reflex actions.

Flexor-extensor reflex

A protective spinal reflex that withdraws a limb.

Spinal tract

A bundle of nerve fibers named for its origin and termination.

Cauda equina

Collection of nerve roots at the end of the spinal cord.

Hypothalamus

Brain region controlling bodily functions and hormone release.

Pituitary gland

The master gland producing hormones affecting other glands.

Pineal gland

Gland regulating circadian rhythm and producing melatonin.

Reticular formation

A neural network regulating consciousness and arousal.

Primary motor area

Part of the brain controlling voluntary movements.

Frontal lobe

Brain region responsible for higher-level cognitive functions.

Parietal lobe

Processes sensory information from the body.

Cerebrovascular accident (CVA)

A stroke caused by interrupted blood flow to the brain.

Basal nuclei

Brain structures that initiate and control voluntary movements.

Parkinson's disease

A neurodegenerative disorder caused by loss of dopamine.

Anterior root

Contains motor neurons carrying signals away from CNS.

Posterior root

Contains sensory neurons carrying signals towards the CNS.

Dermatome

Skin area supplied by a single spinal nerve.

Referred pain

Pain felt in a different location from the source.

Acetylcholine

Neurotransmitter released by all preganglionic fibers.

Cranial nerves

Twelve pairs of nerves emerging directly from the brain.

Limbic system

Brain structure involved in emotional responses.

Olfactory receptors

Proteins detecting odors in the nasal epithelium.

Baroreceptors

Receptors detecting changes in blood pressure.

Nociceptors

Receptors detecting pain stimuli.

Thermoreceptors

Receptors detecting temperature changes.

Proprioceptors

Receptors providing information about body position.

Muscle spindles

Proprioceptive organs detecting muscle length changes.

Primary taste sensations

Sweet, sour, salty, bitter, and umami.

Refraction of light

Bending of light when passing between media.

Cornea

Main structure refracting light entering the eye.

Cataract

Clouding of the eye's natural lens.

Conductive hearing loss

Hearing loss due to outer or middle ear issues.

Sensorineural hearing loss

Hearing loss due to inner ear or auditory nerve issues.

Nearsightedness (myopia)

Condition making far objects appear blurry.

Farsightedness (hyperopia)

Condition making nearby objects appear blurry.

Eustachian tube

Tube connecting the middle ear to the throat.

Fovea centralis

Area of highest visual acuity in the retina.