cells and tissues of the nervous system

Question 1

how many pairs of cranial nerves are there?

Answer 1

12

Question 2

how many pairs of spinal nerves are there?

Answer 2

33

Question 3

what are the two populations of cells that make up the nervous system?

Answer 3

neurons

glial cells

Question 4

what are some features of neurons?

Answer 4

structural and functional unit
excitable cells
impulses carried as action potential

Question 5

what are some functions of glial cells

Answer 5

non excitable supporting cells

much smaller than neurons

Question 6

what is a typical neuron composed of?

Answer 6

multiple dendrites, one axon

Question 7

how many directions can action potentials travel in?

Answer 7

1 - from the cell body to the synaptic terminal

Question 8

what comprises the nucleus of neurons?

Answer 8

loose chromatin

prominent nucleolus

Question 9

what organelles are contained within neurons?

Answer 9

mitchondria
rER
diffuse golgi aparatus

Question 10

what part of the neuron can grow back?

Answer 10

the axon

Question 11

what part of the neuron does not grow back after damage?

Answer 11

cell body

Question 12

what is the purpose of the myelin sheath?

Answer 12

increases conduction speed in axons by saltatory conduction

Question 13

what are myelin sheaths formed by?

Answer 13

schwann cells in PNS

oligodendrocytes in CNS

Question 14

what happens if the myelin sheath becomes dysfunctional?

Answer 14

nerve conduction across the affected axons is abnormal

Question 15

what is seen on an MRI of a patient with multiple sclerosis?

Answer 15

whitish plaques of demyelination

Question 16

what are 3 types of neurons?

Answer 16

multipolar
bipolar
pseudounipolar

Question 17

what type of neuron comprises ALL sensory neurons?

Answer 17

pseudounipolar

Question 18

where is the head of the neuron located in a pseudounipolar neuron?

Answer 18

dorsal root ganglion

Question 19

what is the name of a collection of grey matter in the CNS?

Answer 19

nucleus

Question 20

what is the name for a collection of grey matter outside the CNS?

Answer 20

ganglion

Question 21

what forms tracts?

Answer 21

collections of myelinated axons

Question 22

what is a tract?

Answer 22

bundles of axons carrying specific information within the white matter

Question 23

what forms white matter?

Answer 23

collections of myelinated axons

Question 24

what are astrocytes?

Answer 24

most common type of glial cell- they surround synapses and capillaries and help in K+ buffering

Question 25

what is the function of microglia?

Answer 25

phagocytosis and scar formation

Question 26

what does the cerebellum do?

Answer 26

controls balance and coordination

Question 27

what are the 3 divisions of the brainstem?

Answer 27

pons medulla midbrain

Question 28

what makes up the diencephalon?

Answer 28

thalamus | hypothalamus

Question 29

what does the cavity of the neural tube persist as in the adult brain?

Answer 29

ventricles

Question 30

what is contained within the ventricles?

Answer 30

CSF

Question 31

what are the names of the different ventricles?

Answer 31

lateral - 2 III ventricle cerebral aqueduct IV ventricle

Question 32

what connects the lateral ventricles with the 3rd ventricle?

Answer 32

interventricular foramen

Question 33

where do the lateral ventricles lie?

Answer 33

cerebral hemispheres

Question 34

where does the the III ventricle lie?

Answer 34

cavity within diencephalon

Question 35

where does the cerebral aqueduct lie?

Answer 35

midbrain

Question 36

where does the 4th ventricle lie?

Answer 36

hindbrain

Question 37

what are the 3 coverings of the CNS?

Answer 37

dura mater arachnoid mater pia mater

Question 38

what is contained within the subarachnoid space?

Answer 38

CSF

Question 39

what is the function of the ventricles?

Answer 39

secrete CSF

Question 40

what is contained within the subdural space?

Answer 40

blood vessels penetrating into the CNS

Question 41

where is CSF formed?

Answer 41

choroid plexus in each ventricle

Question 42

where is CSF absorbed?

Answer 42

by arachnoid villi into saggital sinus (venous channel in the brain)

Question 43

what do dural folds do?

Answer 43

keep the various parts of the brain in place

Question 44

what are the names of the dural folds?

Answer 44

falx cerebri tentorium cerebelli falx cerebelli diaphragma sellae

Question 45

what is the blood brain barrier?

Answer 45

protective mechanism that helps maintain a stable environment for the brain and prevents harmful amino acids and ions present in the bloodstream and blood cells from entering the brain

Question 46

what composes the blood brain barrier?

Answer 46

1. endothelium - tight junction 2. thick basal lamina 3. foot processes of astrocytes

Question 47

where is the BBB absent?

Answer 47

parts of the hypothalamus | posterior pituitary

Question 48

what can pass freely across the blood brain barrier?

Answer 48

lipid soluble molecules oxygen water

Question 49

how do water soluble molecules pass the blood brain barrier?

Answer 49

they are pump mediated