Neurological System

Question 1

Dendrites

Answer 1

Receives electrical signals FROM other neurons

Question 2

Axon

Answer 2

Transmits electrical signal TO other neurons

Question 3

Glial cells

Answer 3

Supporting cells for functioning of the brain. Three types in CNS are: astrocytes, oligodendrocytes, microglia. One in PNS is: Schwann Cell

Question 4

Astrocytes

Answer 4

Looks like “stars” surrounding the capillaries of the brain. Nutrient supplier and toxin filter, forms tight junctions with the capillaries. The filtering property is referred to as “blood-brain barrier.”

Question 5

Schwann cells

Answer 5

Forms supporting structure for nerves (unlike astrocytes, which is for capillary). Myelinated nerves have Schwann cells that wrap around the nerve outside the myelination, and un-myelinated nerves have Schwann cells that do not wrap, but simply support the nerve fiber.

Question 6

Gray and white matter in terms of myelination

Answer 6

gray = no myelination, white = myelination

Question 7

Resting Membrane Potential

Answer 7

-70mV, for neurons. Na-K pump maintains this -70mV difference. Na-K pump lets three Na out two K in, so net potential is negative.

Question 8

Depolarization of neuron

Answer 8

Neuron gets excitory stimulus, and when enough signal causes sodium gates to open (and Na rushes in to depolarize) this occurs. +30mV is reached at the end of depolarization.

Question 9

Repolarization of neuron

Answer 9

After depolarization, potassium gates open and K gets out to polarize the electrical system. Sodium gates close at the same time.

Question 10

Hyperpolarization of neuron

Answer 10

After repolarization, potassium gates close and a brief moment where larger than 70mV voltage difference occurs.

Question 11

Refractory period

Answer 11

Repolarization + hyperpolarization period is referred to as this, since no stimulus can cause the system to react. This period is also necessary to stop electrical signal from traveling the opposite way.

Question 12

Nodes of Ranvier

Answer 12

Saltatory conduction occurs due to this structure. The myelin sheath prevents normal influx of Na+ and helps propagate signal more efficiently.

Question 13

Chemical Synapse, Synaptic Cleft

Answer 13

Electrical signal causes release of chemicals (neurotransmitters) which travel through this

Question 14

Role of Ca++ in Synapse

Answer 14

When action potential reaches the synaptic knob, calcium gates open and let calcium in. Vesicles containing neurotransmitter merge with synaptic knob, releasing the chemicals.

Question 15

Neurotransmitters

Answer 15

Can be inhibitory or excitatory. K+/Cl- opening will hyperpolarize and thus inhibit. K+/Na+ opening will depolarize and thus excite. Either direct or second messenger stimulation of gated channels can occur.

Question 16

Ventricles of the Brain

Answer 16

Fluid-filled parts on the brain.

Question 17

Sulcus, Gyrus

Answer 17

Respectively, parts of the brain that fold inward (valley), parts of the brain that fold outward (trough).

Question 18

Cerebrum

Answer 18

Contains cortex and corpus callosum, the outer parts of the brain that we normally associate with folding.

Question 19

Diencephalon

Answer 19

Contains thalamus, pineal body, hypothalamus

Question 20

Brain stem

Answer 20

Contains midbrain, pons, medulla oblongata

Question 21

Four lobes of cerebrum

Answer 21

Frontal, occipital, parietal, temporal

Question 22

Superior frontal gyrus

Answer 22

Located in frontal lobe, located nearest to center and cuts frontal lobe in half vertically. Left and right brain both has superior frontal gyrus.

Question 23

Central sulcus

Answer 23

Separates the frontal lobe from parietal lobe, cuts entire brain in half horizontally.

Question 24

Inferior temporal gyrus

Answer 24

Bottom left/right gyrus in brain in temporal lobe

Question 25

Superior temporal gyrus

Answer 25

This gyrus borders frontal lobe from temporal robe

Question 26

Hippocampus

Answer 26

Spatial navigation, consolidation of short term memory to long term memory. Located near the midbrain, one on both sides of the brain

Question 27

Sylvian fissure

Answer 27

Fissure between temporal and frontal brain

Question 28

Precentral and Postcentraul Gyrus

Answer 28

Motor and sensory information processed (respectively), located near the central sulcus of the frontal brain. Called sensorimotor strip.

Question 29

Parieto-occipital fissure

Answer 29

Fissure between parietal and occipital lobes

Question 30

Calcarine fissure

Answer 30

Fissure in the occipital lobe responsible for visual information processing

Question 31

Cerebellum

Answer 31

Posture, coordination, timing/precision of movements

Question 32

Brainstem

Answer 32

Respiration, heart function, gastrointestinal motor. Conducts electricity from spinal cord to cerebral cortex. Includes pons, medulla oblongata, and midbrain.

Question 33

Medulla oblongata

Answer 33

Involuntary functions of the heart, respiratory, and gastrointestinal

Question 34

Pons

Answer 34

Contain clusters of neurons (is a nuclei) that deal with sleep, respiration, swallowing, bladder control, eye movement, facial sensation, etc. Relays information between cerebellum and cerebral cortex.

Question 35

Basal ganglia

Answer 35

Located right below the cerebrum, curved shape. Habits, obsessive-compulsive behaviors, addiction, emotional response. Includes globus pallidus, putamen, caudate.

Question 36

Globus pallidus

Answer 36

Regulates voluntary movements, looks like a disk. Surrounds the thalamus.

Question 37

Putamen

Answer 37

Regulates voluntary movements, looks like a fruit on a branch (hence the name, from greek origins)

Question 38

Caudate nucleus

Answer 38

Regulates voluntary movements, looks like a ring

Question 39

Thalamus

Answer 39

Regulates consciousness, sleep, alertness. Surrounds the mid-brain, two parts on left and right.

Question 40

Commissural, association, and projection fibers of the white matter

Answer 40

Respectively, axon fibers that connect one cerebral hemisphere to the other, connect one cerebral hemisphere to itself or the basal ganglia, and connect cerebrum and basal ganglia to the spinal cord.

Question 41

Optic chiasm

Answer 41

Part of the optic nerves that cross each other. Located below cerebrum, in front of midbrain. Can be seen as fibers behind eyes that cross like an X.

Question 42

Cerebrospinal fluid

Answer 42

Provides buoyancy to brain to prevent blocking of blood vessels, cushions cortex from damage, protects cortical neurons from toxins through cleansing of this

Question 43

CSF Flow

Answer 43

Generated in choroid plexus of lateral ventricle (the ventricle most near the center of the brain), into 3rd ventricle (below the lateral ventricle), then into 4th ventricle located way below 3rd ventricle. Flows through the rest of the brain below skull and below superior sagittal sinus, in subarachnoid space. Absorbed over time into venous blood of superior sagittal sinus.

Question 44

Aqueduct of Sylvius

Answer 44

Connects 3rd and 4th ventricle, shows as small opening at the center of the brain in MRI scans.

Question 45

Brain coverings

Answer 45

From outside to inside, skull, dura mater, arachnoid, pia mater. Arachnoid is filled with spider-like projections.

Question 46

Spinal cord composition

Answer 46

White matter for communication with the brain, gray matter for reflex arc. Dorsal (back) and ventral (front) roots connect to spinal cord, conveys sensory and motor information, respectively (like how precentral gyrus is in front and controls motor, and how postcentral gyrus controls sensory).

Question 47

Infundibulum

Answer 47

Stalk that connects to pituitary gland

Question 48

Three types of three-neuron reflex arcs

Answer 48

Ipsilateral (motor and sensory from same side of the body), contraleteral (sensory ennervates motor on the other side of the body), intersegmental (sensory ennervates motor on different columns of spine)

Question 49

Locations of major autonomic pathways

Answer 49

Sympathetic: influences the body with nerves from the thoracic (upper five spines) and lumbar levels (bottom spines) of the spinal cord. Usually accompanied by ganglia parallel to the spine. Parasympathetic: influences the body with nerves from the brain stem (vagus nerves) and nerves from the sacral ("tail bone") regions.

Question 50

Cranial X nerve

Answer 50

Another name for vagus nerve, which is primarily motor/sensory nerve for autonomic parasympathetic system.