21 - The Nervous System

Question 1

CNS, central nervous system consists of…

Answer 1

the brain and spinal cord

Question 2

afferent nerve

Answer 2

sensory nerve

-transmits impulses to the nervous system

Question 3

efferent nerve

Answer 3

motor nerve

-transmits impulses from brain or spinal cord to muscle

Question 4

• destruction of motor neurons by disease
• interruption of reflex arc responsible for muscle tone
• muscle deprived of innervation
• low muscle tone
• peripheral nerve destruction

Answer 4

Flaccid paralysis

Question 5

• reflex arc not disturbed
• injury to cortical neurons stops voluntary control
• muscle retains innervation
• increased muscle tone

Answer 5

spastic paralysis

Question 6

anencephaly

Answer 6

• failure of normal development of brain and cranial cavity

- multifactorial inheritance

Question 7

-alpha-fetoprotein leaks from fetal blood into amniotic fluid through open neural tube defect; high levels found in amniotic fluid

Answer 7

spina bifida

Question 8

voluntary motor activity is controlled by the _____________ system and the ______________ system.

Answer 8

pyramidal system and extrapyramidal system

Question 9

-controls voluntary motor functions

Answer 9

pyramidal system

Question 10

-regulates muscle groups concerned primarily with balance, posture, and coordination

Answer 10

extrapyramidal system

Question 11

• from congenital obstruction of aqueduct or absence of openings in roof of 4th ventricle
• head enlarges as ventricles dilate because cranial structures have not fused

Answer 11

congenital hydrocephalus

Question 12

protein produced by fetal liver early in gestation. sometimes produced by tumor cells. level is elevated in amniotic fluid when fetus has neural tube defect.

Answer 12

alpha fetoprotein (AFP)

Question 13

• obstruction of cerebral spinal fluid (CSF) by tumor or adhesions blocking opening in 4th ventricle
• ventricles dilate but head does not enlarge because cranial structures are fused

Answer 13

acquired hydrocephalus

Question 14

treatment of hydrocephalus

Answer 14

-inserting a plastic tube into a dilated ventricle and rerouting (shunting) the fluid into another part of the body where it can be absorbed.

Question 15

any injury to brain tissue from disturbance of blood supply to brain

Answer 15

stroke, or cardiovascular accident

Question 16

most common; thrombosis of cerebral artery narrowed by arteriosclerosis

Answer 16

cerebral thrombosis

Question 17

occurs less frequently; blockage of cerebral artery by fragment of blood clot from an arteriosclerotic plaque or from heart

Answer 17

cerebral embolus

Question 18

most serious type of stroke; usually from rupture of a cerebral artery in person with hypertension

Answer 18

cerebral hemorrhage

Question 19

ischemic infarct

Answer 19

no blood leaks into brain

Question 20

hemorrhagic infarct

Answer 20

blood leaks into damaged brain tissue

Question 21

• sclerosis of major artery from aorta that supplies brain

- common affected site: carotid artery in neck; arteriosclerotic plaque may narrow lumen and reduce cerebral blood flow

Answer 21

arteriosclerosis of extracranial arteries

Question 22

cerebral angiogram

Answer 22

• dye is injected into the carotid and vertebral arteries that arise from the arch of the aorta to the brain
• the course of the dye is followed by serial x ray studies

Question 23

temporary cerebral dysfunction as a result of transient obstruction of a cerebral vessel by a bit of atheromatous debris or blood clot usually embolized from an arteriosclerotic plaque in the carotid artery

Answer 23

transient ischemic attack (TIA)

Question 24

About 1/# of patients with TIAs eventually suffer a major stroke.

Answer 24

1/3.

Question 25

• most common type of cerebral aneurysm
• results from a congenital defect in the elastic and muscular tissue of the vessel wall, usually at the point where the artery branches

Answer 25

congenital cerebral aneurysm

Question 26

infection affecting meninges

Answer 26

meningitis

Question 27

infection of brain tissue

Answer 27

encephalitis

Question 28

affects both meninges and brain tissue

Answer 28

meningoencephalitis

Question 29

an inflammation of the grey matter of the spinal cord caused by a virus

Answer 29

poliomyelitis

Question 30

responsible for cases of meningitis and encephalitis

Answer 30

arboviruses

Question 31

-caused by small protein particle produced as a result of gene mutation

Answer 31

Creutzfeldt-Jakob disease

Question 32

characteristics of alzheimer disease

Answer 32

• progressive mental deterioration

- emotional disturbances

Question 33

anatomic and biochemical features of alzheimers

Answer 33

• nuerofibrillary tangles: thickening of neurofilaments
• neurotic plaques: clusters of thick, broken neurofilaments
• biochemical abnormalities: acetylcholine and actylcholine synthesizing enzyme

Question 34

chronic disease characterized by focal areas of demyelination in the central nervous system, followed by glial scarring

Answer 34

multiple sclerosis

Question 35

a large stellate cell having highly branched processes. forms the structural framework of the nervous system. one of the neuroglial cells.

Answer 35

astrocyte

Question 36

a chronic disease of the central nervous system characterized by rigidity and tremor, caused by decreased concentration of dopamine in the central nervous system.

Answer 36

Parkinson disease, treated with L-dopa

Question 37

• progressive hereditary autosomal dominant disease
• progressive mental deterioration
• abnormal jerky and writhing movements
• first manifestations between age 30 to 50 years
• no way to arrest the disease

Answer 37

Huntington Disease

Question 38

a benign tumor arising from the meninges

Answer 38

meningioma

Question 39

any brain tumor arising from glial (supporting) cells of the brain

Answer 39

glioma

Question 40

a malignant neoplasm of plasma cells

Answer 40

multiple myeloma

Question 41

an inflammation of multiple nerves

Answer 41

polyneuritis