Introduction and Gross Brain

Question 1

what is the bony structure surrounding the brain?

Answer 1

skull

Question 2

what is the bony structure surrounding the spinal cord?

Answer 2

vertebral canal

Question 3

what type of muscle is innervated by fibers of the somatic nervous system?

Answer 3

allows for contraction of striated muscle

provides sensation from the external environment to the level of consciousness

Question 4

how many angular degrees separate the horizontal plane from the coronal plane?

Answer 4

90 degrees

Question 5

name the three embryological subdivisions of the brain

Answer 5

rhombencephalon- most caudal subdivision
mesencephalon- midbrain
prosencephalon- cerebrum

Question 6

name the minor subdivisions of the hindbrain and forebrain

Answer 6

rhombencephalon- myelencephalon (medulla oblongata) and metencephalon (pons and cerebellum)
prosencephalon- diencephalon (in between brain) and telencephalon- cerebral hemispheres and corpus striatum of the basal ganglia

Question 7

what are the ventricular cavities of each of the subdivisions of the brain?

Answer 7

spinal cord- central canal
rhombencephalon- 4th ventricle
midbrain- cerebral aqueduct
diencephalon- 3rd ventricle
telencephalon- lateral ventricles (1st and 2nd)

Question 8

name the structural and functional unit of the nervous system

Answer 8

neuron. receive and transmit bioelectrical signals: to and from other neurons
from specialized receptors
to and from muscles and glands

Question 9

list the twelve cranial nerves by name and number

Answer 9

I – Olfactory
	II – Optic
	III – Oculomotor
	IV – Trochlear
	V – Trigeminal
		V1 – Opthalmic Division
		V2 – Maxillary Division
		V3 – Mandibular Division
	VI – Abducens
	VII – Facial
	VIII – Vestibulocochlear
	IX – Glossopharyngeal
	X – Vagus
	XI – Accessory
	XII - Hypoglossal

Question 10

name the components of brainstem

Answer 10

medulla oblongata
pons
midbain

Question 11

name the lobes of the cortex

Answer 11

Frontal – motor
Temporal – hearing
Parietal – direction of frontal cortex, touch
Occipital – vision

Question 12

name the borders of each of the lobes of the cortex laterally

Answer 12

frontal lobe lies rostral to the central sulcus and superior to lateral fissure
occipital lobe lies behind an imaginary line drawn from parieto-occipital sulcus to the preoccipital notch
temporal lobe lies below the lateral fissure and an imaginary extension drawn caudally to the occipital lobe
parietal lobe occupies the remainder of the lateral surface

Question 13

name the borders of each of the lobes of the cortex medially

Answer 13

frontal lobe lies above corpus callosum and rostral to central sulcus
occipital lobe lies behind the parieto-occipital sulcus
parietal lobe lies in between
temporal lobe lies in front of the occipital lobe and lateral to the brainstem

Question 14

ipsilateral

Answer 14

the axon (tract) courses and/or terminate on the same side as its cell body (nucleus)

Question 15

contralateral

Answer 15

the axon (tract) courses and/or terminates on the side opposite its cell body (nucleus

Question 16

bilateral

Answer 16

the axon (tract) divides and courses and/or terminate on both sides

Question 17

decussation

Answer 17

fibers ascend/descend as they cross

Question 18

commissure

Answer 18

fibers pass directly from one side to the other

Question 19

list the three meninges

Answer 19

dura mater- 2 layers- outer- endosteum of the skull
inner- meningeal layer of dura
arachnoid mater- thin layer that adheres tightly to the inside of the dura
pia mater- layer that immediately covers the brain

Question 20

list the two clinically significant potential meningeal spaces

Answer 20

epidural space- potential space between the skull and dura mater
subdural space- potential space between the dura mater and the arachnoid

Question 21

major blood supply to the dura over the parietal lobe

Answer 21

middle meningeal artery and branches

Question 22

epidural hematoma

Answer 22

result of blood entering the epidural space; often the result of damage to the middle meningeal artery
expanding hematoma puts pressure on the brain

Question 23

subdural hematoma

Answer 23

result of blood entering the subdural space; often the result of damage to small veins

Question 24

what is the rostral extent of the subarachnoid space along the optic nerve?

Answer 24

The optic nerve is a tract within the brain.
Meninges cover the optic nerve.
The subarachnoid space extends along the optic nerve to the back of the eye.
An abnormal increase in CSF pressure (hydrocephalus) is reflected by changes in the optic papilla (choked disk; papilledema).

Question 25

what is the falx cerebri? what does it separate?

Answer 25

it is a dural septae formed by dura mater reflecting upon itself. The falx extends ventrally in the sagittal plane from the skull to the corpus callosum and separates the cerebral hemispheres. The superior sagittal sinus occupies the upper edge of the falx.

Question 26

what is the tentorium cerebelli? what does it separate?

Answer 26

The tentorium separates the cerebellum below from the occipital lobe above. The tentorium extends around the brainstem. The opening created by the brainstem is called the tentorial incisure (notch). The tentorium cerebelli divides the cranial cavity into the: Supratentorial space Infratentorial space

Question 27

supratentorial space contains

Answer 27

cerebrum

Question 28

infratentorial space contains

Answer 28

cerebellum

Question 29

what is the origin, course and point of resorptions of cerebrospinal fluid?

Answer 29

``` Cerebrospinal fluid (CSF) is produced by vascular tufts located in the lateral, third and fourth ventricles. CSF exits the ventricular system into the subarachnoidspace. CSF is reabsorbed into the superior sagittal sinus through the arachnoid granulations. ```

Question 30

Name the vessels involved in the posterior (vertebral-basilar) and anterior (internal carotid) blood supply to the brain.

Answer 30

``` Posterior blood supply of brain -Vertebral artery -becomes basilar a. Anterior blood supply of brain -ICA, becomes middle cerebral a. ```

Question 31

vessels of circle of willis

Answer 31

Anterior ICaa. becomes middle cerebral aa., Middle cerebral aa. give off anterior cerebral aa., which is connected by ant. communicating a. Posterior Posterior cerebral aa. connected to ICaa. by post. communicating aa. Posterior cerebral aa. merge to form basilar a. Basilar a. splits posteriorly into vertebral aa. A&P connected by post. communicating aa.

Question 32

3 major vessels that supply cerebral cortex

Answer 32

-anterior, middle, and posterior cerebral aa. Lateral brain -supplied by middle cerebral a. -ant. & post. cerebral aa. wrap around to supply edges near longitudinal fissure Medial brain -superior rostral supplied by anterior cerebral a. -inferior caudal supplied by posterior cerebral a.