Introduction to the Nervous System

Question 1

What is it when a single cell stimulates multiple cells?

Answer 1

Divergence

Question 2

What is it when multiple cells stimulate a single nucleus of another neuron?

Answer 2

Convergence

Question 3

What is the directional term for “toward head”?

Answer 3

rostral

Question 4

What is the directional term for “toward tail”?

Answer 4

caudal

Question 5

What is the directional term for “incoming connections - axons/nerve impulses conducted/directed toward the next neuron”?

Answer 5

afferent (sensory)

Question 6

What is the directional term for “outgoing connections - axons/nerve impulses conducted/directed away from a neuron”?

Answer 6

efferent (motor)

Question 7

What develops into the spinal cord and the brain (CNS)?

Answer 7

neural tube

Question 8

The neural crest cells that were left behind eventually form the majority of what?

Answer 8

Peripheral Nervous System (PNS) including the dorsal root ganglia cells that are the cell bodies for all of the sensory side of the PNS, Schwann cells, and the ganglia of the autonomic nervous system.

Question 9

What are the cells that myelinate the PNS (both sensory and motor)?

Answer 9

Schwann cells

Question 10

The autonomic nervous system includes what 2 types of cells?

Answer 10

• sensory cells

- postganglionic motor cells

Question 11

Neural crest cells are responsible for the generation of what type of cells found in what layer of the epidermis?

Answer 11

melanocytes in Stratum Basale

Question 12

The neural tube is divided into what four plates?

Answer 12

• roof
• floor
• alar
• basal

Question 13

Which plate of the neural tube is located dorsal to sulcus limitans and forms the sensory and association part of the developing neural tube?

Answer 13

alar plate

Question 14

Which plate of the neural tube lies anterior to sulcus limitans and forms the motor part of the developing neural tube, including both alpha and gamma motor neurons?

Answer 14

basal plate

Question 15

Which two plates of the neural tube do not generate any neuronal components?

Answer 15

roof and floor plates

Question 16

What is the groove in the wall of the neural tube called?

Answer 16

sulcus limitans

Question 17

What two plates of the neural tube are separated by the sulcus limitans?

Answer 17

alar and basal plates

Question 18

The developing neural tube expands at the rostral end into what three primary vesicles?

Answer 18

• rhombencephalon
• mesencephalon
• prosencephalon

Question 19

What two secondary vesicles does the rhombencephalon further expand into?

Answer 19

• myelencephalon

- metencephalon

Question 20

What two secondary vesicles does the prosencephalon further expand into?

Answer 20

• diencephalon

- telencephalon

Question 21

The primary vesicle, mesencephalon, forms what brain region?

Answer 21

midbrain

Question 22

The secondary vesicle, myelencephalon, forms what brain region?

Answer 22

medulla oblongata

Question 23

The secondary vesicle, metencephalon, forms what brain region?

Answer 23

pons and cerebellum

Question 24

The secondary vesicle, diencephalon, forms what brain region?

Answer 24

thalamus and hypothalamus

Question 25

The secondary vesicle, telencephalon, forms what brain region?

Answer 25

cerebral hemispheres, basal ganglia

Question 26

Secondary brain vesicles result in the formation of what?

Answer 26

brain and brainstem

Question 27

The remainder of the neural tube, besides the secondary brain vesicles, forms what?

Answer 27

spinal cord

Question 28

The lumen of the neural tube expands with the developing vesicles and forms what?

Answer 28

the ventricular system

Question 29

What is continuous with the central canal of the spinal cord (a remnant of the neural tube)?

Answer 29

the ventricular system

Question 30

What secondary brain vesicle has two lateral ventricles?

Answer 30

telencephalon (cerebral hemispheres)

Question 31

What secondary brain vesicle contains the third ventricle of the brain (midline unpaired ventricle)?

Answer 31

diencephalon

Question 32

Where in the brain can you find the fourth midline unpaired ventricle?

Answer 32

found in the pons and medulla and below the cerebellum

Question 33

What divides the cerebral hemispheres from each other and from the cerebellum?

Answer 33

longitudinal and transverse fissures

Question 34

What divides the frontal lobe and parietal lobe (pre- and post central gyri - primary motor and sensory cortices)?

Answer 34

central sulcus

Question 35

What is the midline extension of the pre- and post central gyri called?

Answer 35

paracentral lobule

Question 36

What divides the temporal lobe from the frontal and parietal lobe?

Answer 36

lateral sulcus

Question 37

An imaginary line stretching between what two areas separates the occipital lobe from the parietal and temporal lobes?

Answer 37

parieto-occipital notch and pre-occipital notch

Question 38

What is the midline sulcus marking the area of the primary visual cortex called?

Answer 38

calcarine sulcus

Question 39

What separates the midline part of the occipital lobe from the parietal lobe?

Answer 39

parieto-occipital sulcus

Question 40

What is known as the midline sulcus?

Answer 40

Cingulate sulcus

Question 41

What are the connective tissue membranes covering the CNS called?

Answer 41

meninges

Question 42

Most external layer and toughest layer covering the CNS?

Answer 42

Dura mater

Question 43

Enfolding of the meningeal layer of the dura mater results in the formation of what openings between the two layers of the dura?

Answer 43

Dural sinuses

Question 44

What function as the outflow pathway for venous blood and cerebrospinal fluid?

Answer 44

dural sinuses

Question 45

Due to the rigidity of the attachments of the dural sinuses to the brain, space occupying lesions cause what clinical problem?

Answer 45

herniations

Question 46

What layer of the dura is fused with the periosteum of the skull at the foramen magnum?

Answer 46

periosteal dura

Question 47

What layer of the dura is continuous into the vertebral canal and covers the spinal cord?

Answer 47

meningeal dura

Question 48

What structure of the dura separates the cerebral hemispheres?

Answer 48

Falx cerebri

Question 49

What structure of the dura separates the cerebral hemispheres from the cerebellu, also limiting the posterior cranial fossa?

Answer 49

Tentorium cerebelli

Question 50

What is the opening in the tentorium cerebelli surrounding the brainstem (midbrain) as it passes out of the middle cranial fossa into the posterior cranial fossa called?

Answer 50

Tentorial notch

Question 51

Which dural sinus is on the superior edge of falx cerebri?

Answer 51

superior sagittal sinus

Question 52

Which dural sinus is on the inferior edge of falx cerebri?

Answer 52

inferior sagittal sinus

Question 53

Which dural sinus connects the inferior and superior sagittal sinuses across tentorial cerebelli?

Answer 53

straight sinus

Question 54

What is the point posteriorly on tentorium cerebelli where the straight sinus and transverse sinuses join called?

Answer 54

confluens of sinuses

Question 55

Which dural sinus are at the posterior edge of tentorium cerebelli and carry venous blood toward the internal jugular vein?

Answer 55

Transverse sinus

Question 56

Which dural sinus is considered the last part of the sinus system that is continuous with the internal jugular vein through the jugular foramen?

Answer 56

Sigmoid sinus

Question 57

What is the "squeezing" of nervous tissue through an opening such as the tentorial notch?

Answer 57

herniation

Question 58

Three common sites of herniation?

Answer 58

1) subfalcine - cingulate gyrus under the falx cerebri 2) transtentorial or uncal - uncus through the tentorium cerebrelli (tentorial notch) 3) tonsillar - cerebellar tonsils through the foramen magnum

Question 59

What is it called when a skull fracture tears the middle meningeal artery resulting in an arterial bleed with blood accumulating between the dura mater and the skull?

Answer 59

epidural hematoma

Question 60

What is the delicate non-vascular connective tissue membrane layer of the brain?

Answer 60

arachnoid mater

Question 61

What are the attachments from the outer arachnoid layer to the pia mater called?

Answer 61

arachnoid trabeculae

Question 62

What is the potential space between the dura and the arachnoid called?

Answer 62

subdural space

Question 63

Are the arachnoid and dura attached?

Answer 63

NO

Question 64

Venous bleeding into the potential space between the dura and the arachnoid is called what?

Answer 64

subdural hematoma

Question 65

What are small extensions of the arachnoid membrane that function as a "one-way" gate for the uptake of CSF into the venous vascular drainage of the brain?

Answer 65

arachnoid granulations or villae

Question 66

What is the vascular connective tissue membrane of the brain called?

Answer 66

pia mater

Question 67

What is the space called that lies between the pia mater and arachnoid mater and contains CSF?

Answer 67

subarachnoid space

Question 68

What are enlarged areas of subarachnoid space called?

Answer 68

cisterns

Question 69

What can be identified in the subacrachnoid space?

Answer 69

the arterial and venous branches that supply the cortical regions for the brain

Question 70

What is it when there is bleeding in the subarachnoid space resulting from a trauma?

Answer 70

subarachnoid hemorrhage

Question 71

How is the spinal cord anchored within the spinal canal?

Answer 71

the pia intima that is adhered tightly to the spinal cord and the denticulate ligaments that are segmentally paired extensions that cross the subarachnoid space, pierce the arachnoid mater and attach to the dura

Question 72

What are the cavities within the CNS, derived developmentally from the neural tube?

Answer 72

ventricles

Question 73

What substance do ventricles produce?

Answer 73

Cerebrospinal fluid (CSF)

Question 74

What ventricles occur in each of the two cerebral hemispheres?

Answer 74

lateral ventricles

Question 75

Lateral ventricles are continuous with what?

Answer 75

a single midline third ventricle through interventricular foramen (of Monro)

Question 76

The third ventricle is continuous caudally with what?

Answer 76

the cerebral aqueduct of Sylvius in the midbrain

Question 77

The cerebral aqueduct empties into what?

Answer 77

fourth ventricle of the pons and medulla

Question 78

What is the fourth ventricle continuous with?

Answer 78

the remnants of the central canal of the spinal cord

Question 79

The fourth ventricle communicates with the subarachnoid space through what structures?

Answer 79

- two lateral apertures (Foramina of Lushka) | - one midline aperture (Foramen of Magendie)

Question 80

What is secreted by the ependymal cells that line the ventricular system?

Answer 80

Cerebrospinal fluid (CSF)

Question 81

Function of CSF?

Answer 81

reduces the relative mass of the brain and also cushions the brain

Question 82

What can result in the build up of interventricular pressure and/or intracranial pressure?

Answer 82

any blockage of the flow of CSF

Question 83

What results from blockage of normal flow of CSF our of the ventricular system?

Answer 83

Obstructive hydrocephalus

Question 84

What results from absorption or circulation problems with CSF?

Answer 84

Communicating hydrocephalus

Question 85

What joins the endothelial cells of the blood capillaries in the CNS?

Answer 85

tight junctions (forms a barrier that allows for the selective exchange of only small molecules - blood brain barrier)

Question 86

What substances are actively transported across the blood brain barrier for the nourishment of the CNS?

Answer 86

glucose and amino acids

Question 87

What substances are restricted from crossing the blood brain barrier?

Answer 87

large proteins (ex: antibiotics)

Question 88

What types of cells control the permeability of the endothelial cells by influencing the physiology of endothelial cell membranes?

Answer 88

glial cells

Question 89

What happens to the blood brain barrier if the glial cells are disrupted?

Answer 89

the glial cells no longer control the endothelial cells and the barrier is made more permeable

Question 90

Those areas of high activity show the _________ uptake of necessary substances across the blood brain barrier. An increase in perfusion rate of the capillary beds is found in areas of ________ physiological activity along with the ________ areas of oxygen uptake.

Answer 90

highest; greatest; greatest