Neurohistology

Question 1

What defines the CNS anatomically?

Answer 1

Brain and spinal cord

Question 2

Brings sensory information from the periphery to the CNS (type of nerve)

Answer 2

Afferent

Question 3

Takes motor information from CNS to periphery (type of nerve)

Answer 3

Efferent

Question 4

Location of neuronal cell bodies in the CNS (2)

Answer 4

Grey matter and deep nuclei

Question 5

Location of neuronal cell bodies in the PNS

Answer 5

ganglia

Question 6

Location of axons in the CNS

Answer 6

white matter

Question 7

Location of axons in the PNS

Answer 7

nerves

Question 8

Types of supporting cells (glia) present in the CNS (4)

Answer 8

1) astrocytes
2) oligodendrocytes
3) microglia
4) ependymal cells

Question 9

Types of supporting cells (glia) present in the PNS (2)

Answer 9

Schwann cells and satellite cells

Question 10

Another name for neuronal soma

Answer 10

perikaryon

Question 11

Nissl body composition (2)

Answer 11

Rough endoplasmic reticulum and polyribosomes

Question 12

Residue of lysosomal breakdown. Contain lipids and pigments. Accumulates with age.

Answer 12

Lipofuscin

Question 13

Motor protein involved in anterograde transport

Answer 13

kinesin

Question 14

Motor protein involved in retrograde transport

Answer 14

dynein

Question 15

Which is slower, anterograde or retrograde transport in axons?

Answer 15

anterograde

Question 16

[Morphological classification] Multiple dendritic processes. Characteristic of motor neurons and interneurons.

Answer 16

multipolar neuron

Question 17

[Morphological classification] One main dendrite and one axon. Characteristic of special sensory neurons (vision, olfaction, hearing)

Answer 17

bipolar neuron

Question 18

[Morphological classification] Single bidirectional axon-peripheral process (transmitting from the periphery) and a central process (transmitting information to the CNS). Characteristic of sensory neurons in the dorsal root ganglia.

Answer 18

unipolar neuron

Question 19

Most numerous glial cell type in the brain

Answer 19

astrocytes

Question 20

Two types of astrocytes

Answer 20

1) Fibrous Astrocytes (present in white matter)

2) Protoplasmic Astrocytes (present in gray matter)

Question 21

Supportive functions of astrocytes (4)

Answer 21

1) forming the blood-brain barrier
2) nutritional support
3) uptake of neurotransmitters
4) regulate extracellular ionic concentrations

Question 22

These glia line the ventricles of the brain and central canal of the spinal cord. Apical ends have cilia and microvilli

Answer 22

Ependymal cells

Question 23

Cells responsible for producing cerebrospinal fluid

Answer 23

Ependymal cells

Question 24

Microglia are derived from what type of cell

Answer 24

Monocytes

Question 25

Small glial cells with mobile processes that sense the environment -- important for immune surveillance

Answer 25

Microglia

Question 26

Smaller cell with several cytoplasmic extensions (can myelinate multiple internodes of multiple neurons), responsible for myelinating axons in the CNS

Answer 26

Oligodendrocytes

Question 27

Protective insulation from the cell membranes of supporting cells that concentrically wrap around a section of the axon

Answer 27

myelin sheath

Question 28

What's different about Schwann cells as opposed to oligodendrocytes in terms of how it wraps neurons?

Answer 28

One Schwann cell wraps one internode of one neuron

Question 29

True or false: Small diameter axons which are unmyelinated are still enveloped by Schwann cells

Answer 29

True! Multiple axons are enveloped by a Schwann cell but they're not individually wrapped like with myelination. It's not layered

Question 30

Three levels of macroorganization of the brain

Answer 30

1) cerebrum 2) cerebellum 3) brainstem

Question 31

In the spinal cord, is the white matter deep or superficial?

Answer 31

superficial

Question 32

In the brain, is the white matter deep or superficial?

Answer 32

deep

Question 33

Connective tissue membranes that wrap the brain and spinal cord

Answer 33

meninges

Question 34

Outermost and toughest connective tissue membrane in the CNS

Answer 34

dura mater

Question 35

Two layers of the dura mater

Answer 35

1) periosteal layer - attached to the bone of the skull | 2) meningeal layer - closer to the brain itself.

Question 36

The meningeal layer will separate to form _____ and rejoins to form a _____ (formed from two meningeal layers of dura in between hemispheres of the brain)

Answer 36

Dural sinus; dural fold

Question 37

Bleeding between the skull and dura

Answer 37

Epidural hematoma

Question 38

Layer between dura mater and pia mater. Contains spider web-like extensions

Answer 38

Arachnoid matter

Question 39

Located between the arachnoid and pia mater and contains CSF

Answer 39

Subarachnoid space

Question 40

Delicate, highly vascularized layer that is intimately applied to the surface of the brain and spinal cord

Answer 40

pia mater

Question 41

Dural fold that separates the right and left cerebral hemispheres

Answer 41

falx cerebri

Question 42

Gray matter in the cerebrum is found in the ____ ____ layer. Organized into 7 layers

Answer 42

cerebral cortex

Question 43

Three layers of the cerebellar cortex

Answer 43

1) molecular layer 2) purkinje cell layer 3) granular layer

Question 44

Connective tissue layers covering nerves in the PNS (from superficial to deep)

Answer 44

1) epineurium - surrounds entire nerve 2) perineurium - surrounds nerve fibers bundled in fascicles 3) endoneurium - surrounds individual axon

Question 45

The sensory pathway goes through the posterior root ganglion or the anterior root?

Answer 45

posterior root ganglion

Question 46

The motor pathway goes through the posterior root ganglion or the anterior root?

Answer 46

anterior root

Question 47

Discrete organization of CT capsules. Clusters of neuronal soma and myelinated fiber tracts

Answer 47

Sensory Ganglia (Spinal/Dorsal Root Ganglia)

Question 48

Two types of Autonomic (Visceromotor) Ganglia

Answer 48

Sympathetic and parasympathetic ganglia

Question 49

Thin CT capsule. Diffuse arrangement of neuronal soma and thin, indistinct, unmyelinated fiber tracts. Multipolar neurons with satellite and capsule cells. More than 100 neurons usually.

Answer 49

Sympathetic ganglia

Question 50

Indistinct CT capsule. Found in the wall of a target organ. Diffuse arrangement of soma and unmyelinated fiber tracts. Less than 100 neurons usually

Answer 50

Parasympathetic ganglia

Question 51

Responsible for light touch and texture sensation. Found n the dermal papillae of thick skin

Answer 51

Meissner's Corpuscles (Tactile Corpuscles)

Question 52

Responsible for deep pressure, vibration and stretch sensations deep in the dermis.

Answer 52

Pacinian Corpuscles (Lamellar corpuscles)

Question 53

Responsible for proprioception in skeletal muscles

Answer 53

Muscle spindles

Question 54

Responsible for proprioception in tendons

Answer 54

tendon organ

Question 55

Responsible for pain, heat, and cold sensations. Found all over basically lmao

Answer 55

Free nerve endings

Question 56

Responsible for light touch and movement sensation surrounding the hair follicle

Answer 56

Hair receptors

Question 57

What do free nerve endings and hair receptors have in common?

Answer 57

they're unencapsulated

Question 58

Specialized mucosa found on the dorsum of the tongue

Answer 58

lingual papillae

Question 59

Smallest and most numerous papillae. Have keratinized tips and are important in sensing the texture of food. NOT associated with taste buds

Answer 59

filiform papillae

Question 60

Four types of lingual papillae

Answer 60

1) filiform papillae 2) fungiform papillae 3) circumvallate papillae 4) foliate papillae

Question 61

Mushroom shaped papillae that are less abundant than filiform and are scattered widely over the tongue. Taste buds associated.

Answer 61

fungiform papillae

Question 62

Papillae directly anterior to the sulcus terminalis. Taste buds are embedded on the lateral aspects of these papillae.

Answer 62

circumvallate papillae

Question 63

Located on posterolateral aspect of the tongue. They are associated with taste buds but not well developed in humans.

Answer 63

Foliate papillae

Question 64

Barrel-shaped epithelial organs housing taste receptor cells

Answer 64

taste bus

Question 65

Components of taste buds (3)

Answer 65

1) epithelial-derive taste receptors cells 2) supporting cells (sustenacular cells) 3) basal cells (at the bottom of the taste bud)

Question 66

Located in the upper 1/3 of the nasal cavity. Has bipolar neurons specialized for transmission of odor molecules

Answer 66

olfactory epithelium