Chapter 14: The brain and Cranial Nerves

Question 1

when is brain fully grown and what is the final weight?

Answer 1

age 20, 3 lbs

Question 2

brain requires __% of the total O2 content

Answer 2

20%

Question 3

there is permanent damage with more than ___ min without oxygen

Answer 3

5

Question 4

Has a limited storage capacity for ______ and must be continually supplied

deficiency may produce?

Answer 4

glucose

mental confusion, dizziness, convulsions, and unconsciousness

Question 5

major parts of the brain

Answer 5

brain stem, diencephalon, cerebrum, and cerebellum

Question 6

Protective Covering of the Brain

Answer 6

cranial bones and the cranial meninges which are continuous with the spinal meninges

Question 7

2. Three extensions of the meningeal layer of the dura mater that separate parts of the brain

Answer 7

a. Falx Cerebri:
b. Falx Cerebelli:
c. Tentorium Cerebelli

Question 8

Falx Cerebri

Answer 8

separate right and left cerebral hemisphere

Question 9

falx cerebelli

Answer 9

found between right and left halves of cerebellum

Question 10

tentorium cerebelli

Answer 10

separate cerebellum from occipital lobe

Question 11

Description of Cerebrospinal fluid (CSF):

Answer 11

clear, colorless fluid with a total volume in the adult of 100-200 ml

Question 12

four (4) CSF filled cavities within the brain

Answer 12

ventrices

1. lateral ventricle
2. 3rd ventricle
3. 4th ventricle
4. capillaries

Question 13

1. Lateral Ventricles (or First and Second Ventricles

Answer 13

principle site of CSF production

Question 14

Third Ventricle

Answer 14

drains the lateral ventricles

Question 15

Fourth Ventricle

Answer 15

drains 3rd ventricle

Question 16

4. CSF is formed by filtration of blood water through a network of ____________ and __________ cells called __________ _________.

Answer 16

filtration of blood water through network produced at rate 1 liter per dayy and epidemal cells (coroid plexus)

Question 17

C. Pathway of CSF Flow: __________ __________ → __________ __________ → __________ __________ → __________ __________ → __________ _________

Answer 17

lateral ventrices → foramen of monroe → 3rd ventricle → 4th ventricle → aqueduct of sylvius (cerebral aqueduct) → central canal of spinal cord

Question 18

Most of the CSF is reabsorbed by

Answer 18

arachnoid villi of the superior sagittal blood sinus

Question 19

hydrocephalus

Answer 19

if CSF cannot circulate or drain properly due to an obstruction in the ventricles or subarachnoid space, a buildup will occur causing increased pressure on the brain

symptoms: headache, nausea

Question 20

Medulla Oblongata (Develops from the Hindbrain) is Continuous with

Answer 20

upper part of the spinal cord

Question 21

white matter in Medulla oblongata are portions of ______ tracts and _____ tracts

2 parts

Answer 21

portions of myelinated motor (descending) and sensory (ascending) tracts

a. Pyramids: largest motor tracts
b. Decussation: neurons in the left cerebral cortex control skeletal muscles on the right side of the body

Question 22

Gray Matter in medulla oblongata are _____ for origin for CN ____ through ____ and _________ centers

control 4 things

Answer 22

nuclei, CN 8 through 12, autonomic reflex

a. Respiratory (regulates breathing rhythm)
b. Cardiac Control (regulates force and rate of heartbeat)
c. Vasomotor (vessel vasoconstriction)
d. Coughing, vomiting, sneezing, swallowing, and hiccupping

Question 23

Pons (develops from the Hindbrain) separates

Answer 23

medulla from the midbrain

Question 24

White Matter in pons ______ different levels of the brain by way of ______ and relays ______

Answer 24

interconnects, tracts

nerve impulses related to voluntary skeletal movements from the cerebral cortex to the cerebellum

Question 25

Gray Matter in pons are _____ for origin of CN ___ ___ ___ ___ and ______ ______ centers

Answer 25

nuclei, CN 5, 6, 7, 8, pneumotaxic & apneustic

Question 26

Midbrain connects

Answer 26

pons and diencephalon

Question 27

Cerebral Aqueduct transports

Answer 27

CSF

Question 28

White Matter tracts in Midbrain are organized into ____ ______ that convey _____ and _____ impulses

Answer 28

cerebral aqueducts, motor, sensory

Question 29

Gray Matter in Midbrain are _____ for origin for CN ___ and ___ and the ______ _______

Answer 29

nuclei, 3 and 4, corpora quadrigemina (two pairs of rounded nuclei)

Question 30

2 parts of gray matter in midbrain centers for what?

Answer 30

a. Superior Colliculi: visual reflex center | b. Inferior Colliculi: auditory reflex center

Question 31

Reticular Formation

Answer 31

column of gray matter interspersed among fibers of white matter that extends from the medulla to the thalamus

Question 32

Ascending sensory pathways are relayed to the _____ and then the _____

Answer 32

thalamus and then the cerebral cortex

Question 33

Reticular Activating System (RAS) functions

Answer 33

1. regulation of muscle tone (motor function) 2. arousal from sleep (stim from eyes, ears, skin) 3. maintain consciousness & alertness

Question 34

Gray Matter in cerebellum description

Answer 34

convoluted outer surface called the cerebellar cortex

Question 35

Two cerebellar hemispheres are interconnected by region called the __________

Answer 35

vermis

Question 36

Cerebellar Nuclei is made up of

Answer 36

several, gray matter

Question 37

White Matter in cerebellum is found and arranged into 3?

Answer 37

found deep in the cortex three (3) cerebellar tracts called the superior, middle, and inferior cerebellar peduncles

Question 38

cerebellum coordinates all

Answer 38

somatic motor activity

Question 39

superior tract in cerebellum is made up of _____ that carry _____ from _______ to _____ (3)

Answer 39

mostly efferent fibers that carry impulses from cerebellum to midbrain, thalamus and cortex

Question 40

Cerebellar middle tract carries

Answer 40

fibers form cortex

Question 41

inferior cerebellar peduncle

Answer 41

ascending afferent fibers from cord and medulla

Question 42

4 cerebellar functions

Answer 42

1. Error Control in Body Movements: executes the movement intended by the cerebral cortex 2. Predictive Function: detects speed and progress of body movements 3. Efficient Body Movement: influences antagonistic muscles 4. Maintains Muscle Tone: to maintain posture and equilibrium

Question 43

Injury to the cerebellum results in

Answer 43

Cerebellar Ataxia