Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy (MPAS) > Lecture 3: Nervous system II > Flashcards

Lecture 3: Nervous system II Flashcards

1
Q

What is the ventricular system?

A

4 fluid-filled cavities (~150 ml) within the
brain

2 lateral ventricles connected to midline 3rd ventricle (level of diencephalon) by inter- ventricular foramina (foramina of Monro)

3rd ventricle connected to 4th ventricle by the midline cerebral aqueduct (level of midbrain)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Floor and roof of 4th ventricle

A

floor is pons/medulla

roof is cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Flow of CSF in ventricular system

A

2 lateral ventricles into midline 3rd ventricle which drains into 4th ventricle via cerebral aqueduct (narrowest part of icv system)

4th ventricle drains into sub-arachnoid space of cranial cavity median aperture and 2 lateral apertures.

Circulates around brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What produces the CSF? How much?

A

Choroid plexus (highly vascular tissue found within ventricles)

500 ml per day (volume of subarachnoid space is only 150 ml)

Constantly produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the CSF?

A

clear fluid derived from plasma of

the highly vascularized choroid plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does choroid plexus look like?

A

appears as tufts of material in all 4 ventricles (suspended within CSF of ventricles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is choroid plexus made of?

A

specialized epithelial cells that determine which solutes enter the CSF and which don’t

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where is CSF absorbed?

A

Absorbed into blood through arachnoid granulations in venous sinuses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens if production of CSF is higher than absorption?

A

Hydrocephalus

Also happens if CSF accumulates in the ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

CSF functions

A
  1. Provides protection: provides buoyancy of brain within cranium
  2. Maintains constancy of environment for brain tissue (provides nutrients & ions)
  3. Removes cellular waste products – CSF eventually goes to venous blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Composition of CSF

A

relatively constant

change is indication of pathological process (examined by lumbar puncture; lumbar cistern is at base of spinal cord)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What drains the CSF from the subarachnoid space into the venous sinuses?

A

Arachnoid villi (tufts of arachnoid that extend through dura into venous sinus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where are the arachnoid villi most numerous?

A

superior sagittal sinus and are seen as arachnoid granulations

(see figure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What supplies brain oxygen?

A

internal carotid (anterior) and vertebral arteries (posterior)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What part of brain do the internal carotids oxygenate?

A

telencephalon (ant., med., & lat.) and diencephalon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What part of brain do the vertebral arteries oxygenate?

A

posterior & inferior parts of telencephalon (occipital and inferior part of temporal lobes)

brainstem

cerebellum

cervicalspinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Major branches of internal carotid

A
  1. Posterior communicating artery (connects anterior and posterior circulation)
  2. Anterior cerebral artery (medial and superior surfaces of frontal and parietal lobes)
  3. Middle cerebral artery (lateral cortical and subcortical)

(see figure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What connects the anterior cerebral arteries?

A

Anterior communicating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does occlusion of the anterior cerebral artery cause?

A

sensory and motor deficits of the contralateral body (lower limbs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What parts of brain are supplied by the middle cerebral artery?

A

large portion of motor and pre-motor areas in frontal lobe

large area in parietal lobe

superior surface, and anterior pole of temporal lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does occlusion of the middle cerebral artery cause?

A

sensory and motor deficits of the contralateral body (trunk upper limbs, head/face)

language deficits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do the vertebral arteries form?

A

Basilar artery

Basilar artery ascends along the pons before splitting into posterior cerebral arteries (left and right)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What parts of the brain to the posterior cerebrals supply

A

Occipital lobe

Inferior surface of temporal lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What connects the posterior cerebral to the anterior cerebral?

A

Posterior communicating artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do the vertebral arteries supply before forming the basilar artery?

A

Cervical spinal cord via the anterior spinal artery

26
Q

Anterior spinal artery

A

Midline artery

Descends along the anterior medial sulcus of the medulla and the spinal cord

(see figure)

27
Q

Components of the circle of Willis

A
  1. Ant. Cerebral,
  2. Ant. communicating,
  3. Ant. cerebral,
  4. Internal carotid
  5. Post. communicating,
  6. Post. cerebral,
  7. Post. communicating,
  8. Internal carotid
28
Q

What is the advantage of the circle of Willis?

A

Allows the other blood vessels to provide blood in case of blockage

CNS is very metabolically active

Requires uninterrupted blood flow, otherwise neurons will diw

29
Q

Stroke

A

occurs when blood supply to the brain is interrupted

Loss of consciousness, electrical activity ceases, irreversible damage

30
Q

Ischemic stroke

A

Occlusion of vessel

31
Q

Hemorrhagic stroke

A

more commonly involves smaller vessels under chronic hypertension

also subarachnoid hemorrhage (due to aneurysms)

32
Q

What is a sinus?

A

a channel carrying venous blood

All venous blood in the brain drains into a venous sinus (several venous sinuses in the cranial cavity)

Convey venous blood from brain to internal jugular veins

33
Q

Sinus vs vein

A

functionally similar to a vein but has a different structure

34
Q

Pressure of sinuses vs arteries

A

Sinuses have low pressure compared to arteries

35
Q

What are the three midline sinuses that carry the bulk of the brain’s venous blood?

A
  1. Superior sagittal sinus: superior margin of falx cerebri
  2. Inferior sagittal sinus: inferior margin of falx and flows into:
  3. Straight Sinus: junction of cerebral falx and cerebellar tentorium

(see figure)

36
Q

What are the major paired sinuses?

A
  1. Transverse sinus
  2. Inferior Petrosal Sinus
  3. Sigmoid sinus: joins with inferior petrosal to form internal jugular vein

(see figure)

37
Q

Blood flow through venous sinuses from superficial cerebral veins

A

Superficial cerebral veins drain into Superior sagittal sinus which flows into the Confluence, then Transverse, then Sigmoid, then Internal Jugular

The internal jugular vein drains the blood from the brain and returns it to heart

38
Q

Blood flow through venous sinuses from deep cerebral veins

A

Deep cerebral veins drain into the Inferior sagittal sinus to form the Straight sinus into transverse sinus, then Sigmoid, then Internal Jugular

The internal jugular vein drains the blood from the brain and returns it to heart

39
Q

What are the cranial nerves

A

12 pairs of nerves that arise from the brain and innervate head & neck (mainly), but also thorax & abdomen

Nerves may be efferent (i.e., a motor nerve), afferent (i.e., a sensory nerve), or mixed (both sensory and motor fibres)

40
Q

Which nerves arise from the midbrain?

A

III, IV

41
Q

Which nerves arise from the pons?

A

V, VI, VII, VIII

42
Q

Which nerves arise from the medulla?

A

IX, X, XI, & XII

43
Q

12 cranial nerves

A 
I. Olfactory 
II. Optic
III. Occulomotor 
IV. Trochlear
V. Trigeminal 
VI. Abducens
VII. Facial
VIII. Vestibulocochlear
IX. Glossopharyngeal 
X. Vagus
XI. (Spinal) Accessory 
XII. Hypoglossal

Oh Once One Takes The Anatomy Final Very Good Vacations Are Heavenly

44
Q

CNI

A

Olfactory n.

Carries olfactory information from olfactory epithelium through the foramina of cribiform plate

45
Q

CNII

A

Optic n.

Carries visual information from retina through the optic canal

46
Q

CN VIII

A

Vestibulocochlear n.

Carries balance and hearing from inner ear (cochlea and vestibular apparatus) through the internal auditory meatus

47
Q

Sensory nerves:

A

I, II, VIII

48
Q

Cranial nerves: motor

A

3 nerves for extra-ocular muscles (enter orbit through superior orbital fissure): III, IV, VI

XI, XII

49
Q

CN III

A

Occulomotor n.

innervates 4 of the 6 extrinsic muscles of eye, and intrinsic muscles (iris and ciliary body/lens)

50
Q

CN IV

A

Trochlear n.

innervates superior oblique (pulls eye down when adducted)

51
Q

CN VI

A

Abducens n.

innervates lateral rectus (abducts the eye)

52
Q

What is diplopia?

A

Double vision

53
Q

CN XI

A

Spinal Accessory n.

innervates the sternocleidomastiod (rotates the head) & trapezius muscles (shrugs the shoulders).

54
Q

CN XII

A

Hypoglossal n.

innervates the intrinsic and extrinsic muscles of tongue. (sticking out your tongue)

55
Q

Where do CN XI and CN XII exit cranium?

A

CN XI exits cranium via jugular foramen while CN XII exits via hypoglossal canal

56
Q

Mixed cranial nerves

A

V, VII, IX, X

57
Q

CN V

A

Trigeminal n.. 3 branches V1, V2, V3

V1 (Ophthalmic n. - Sup. Orb. Fiss.) – Somatosensory from cornea, nose, and forehead.

V2 (Maxillary n. - f. rotundum) – Somatosensory from maxilla, upper lip & teeth, hard palate.

V3 (Mandibular n. - f. ovale) Somato-sensory mandible, lower lip & teeth, ant. 2/3 tongue; Motor to muscles of mastication

58
Q

CN VII

A

Facial n. (Internal Aud. Meatus)

Sensory – Taste: Ant. 2/3 of Tongue

Motor – Muscles of facial expression

Motor (Visceral) - All glands (salivary) of face/oral cavity except parotid gland

59
Q

CN IX

A

Glossopharyngeal n. (Jugular f.)

Sensory – Taste and somatosensation: Post. 1/3 of
Tongue

Motor – Assist in swallowing

Motor (Visceral) – Parotid gland

60
Q

CN X

A

Vagus n. (Jugular f.)

Sensory – Taste: Epiglottis; Visceral sensory from resp. tract and viscera

Motor – Swallowing (vomiting)

Motor (Visceral) – Respiratory tract, heart, and esophagus, stomach, intestines

61
Q

How to remember function of cranial nerves

A 
I. Olfactory (S) 
II. Optic (S)
III. Occulomot. (M) 
IV. Trochlear (M)
V. Trigeminal (B) 
VI. Abducens (M)
VII. Facial (B)
VIII. Vestibulocochlear (S)
IX. Glossopharyngeal (B) 
X. Vagus (B)
XI. (Spinal) Accessory (M) 
XII. Hypoglossal (M)

Some Say Marry Money, But My Brother Says Big Brains Matter More

Anatomy (MPAS) (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions