Lecture 1 Cells and Tissues of the Nervous System

Question 1

What are the 2 divisions of the PNS

Answer 1

Sensory (afferent)

Motor (efferent)

Question 2

What are the 2 divisions of the Motor (efferent) division

Answer 2

Somatic motor

Autonomic motor

Question 3

The autonomic system can be divided into

Answer 3

Sympathetic and Parasympathetic

Question 4

What are the 2 cell types in the nervous system

Answer 4

Neurons

Glial cells

Question 5

What are neurons

Answer 5

o Structural and functional unit
o Excitable cells
o Impulses carried as action potentials

Question 6

What are Glial cells

Answer 6

o Non-excitable supporting cells

o Much smaller than neurons

Question 7

Describe the typical neuron

Answer 7

One axon

Multiple dendrites

Question 8

What is the path of the action potential

Answer 8

One direction from cell body to synaptic terminal

Question 9

What is the cytoplasm in the cell body called

Answer 9

Perikaryon

Question 10

What is the cytoplasm in the axon called

Answer 10

Axoplasm

Question 11

Define Saltatory conduction

Answer 11

is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials

Question 12

In the PNS myelin sheaths are formed from

Answer 12

Schwann cells

Question 13

In the CNS myelin sheaths are formed by

Answer 13

Oligodendrocytes

Question 14

What is the clinical importance of the myelin sheath

Answer 14

Loss or scarring of myelin sheath leads to abnormal conduction along axons

Question 15

Compartments of the brain

Answer 15

Dorsal columns
Lateral corticospinal tract
Rubrospinal tract
Spinothalmic and spinoreticular tracts
Ventral corticospinal tract
Motoneurons
Ventral spinocerebellar tract
Intermediolateral cell column
Dorsal spinocerebellar tract

Question 16

What are the functions of neuroglia in the PNS

Answer 16

Surround neuronal cell bodies

Myelination

Question 17

What are the functions of the neuroglia in the CNS

Answer 17

Endfeet surround synapses & capillaries and help in K+ buffering
Myelination
Phagocytosis
Scar tissue formation

Question 18

What is the blood brain barrier

Answer 18

Protective mechanism that helps maintain a stable environment for the brain and prevents harmful amino acids & ions present in the blood stream entering the brain

Question 19

What type of drugs are able to enter the CNS

Answer 19

Lipid soluble or use suitable vectors

Question 20

What structures make up the brainstem

Answer 20

Midbrain
Pons
Medulla

Question 21

Where do the lateral ventricles lie

Answer 21

Cerebral hemispheres

Question 22

Where do the 3rd ventricles lie

Answer 22

The cavity within the diencephalon

Question 23

Where does the cerebral aqueduct lie

Answer 23

Midbrain

Question 24

Wheres does the diamond shaped 4th ventricle lie

Answer 24

Hindbrain

Question 25

What are the 3 coverings of the CNS

Answer 25

Dura mater Arachnoid Pia mater

Question 26

What space contains the CSF

Answer 26

Subarchnoid space between arachnoid and Pia mater

Question 27

What forms CSF

Answer 27

Choroid plexus in each ventricle

Question 28

Where is CSF absorbed

Answer 28

• By Arachnoid villi into saggital sinus (venous channel in brain)

Question 29

How does the CSF circulate

Answer 29

Beginning in the lateral ventricles, CSF flows through two passageways into the third ventricle. From the third ventricle it flows down a long, narrow passageway (the aqueduct of Sylvius) into the fourth ventricle. From the fourth ventricle it passes through three small openings (foramina) into the subarachnoid space surrounding the brain and spinal cord.