Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuroscience > Histology of the Central Nervous System > Flashcards

Histology of the Central Nervous System Flashcards

(59 cards)

Start Studying
1
Q

cells that respond to stimuli through electrochemical mechanisms
- Excitable or inhibitory

A

Neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

support cells involved in conduction speed, repair, neurotransmitter maintenance

A

Glia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

dense network of interwoven nerve fibers &

their branches and synapses, together with glial filaments

A

Neuropil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Anatomy of a Neuron

A
  • Cell body with nissl substance/bodies
  • Dendrites with dendritic spines
  • Long axon covered by myelin that emerges from an axon hillock
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The Axon

- site where excitatory or inhibitory stimuli are initiated

A

Initial segment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The Axon
• distal end of the axon
- some have branching, collateral branches

A

Terminal arborization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The Axon

  • small ends of axons
  • Dilation of branch ends & contact postsynaptic cell
A

Telodendria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Structural Classification of Neurons

  • most common, throughout CNS
  • MNs, CNS interneurons
A

Multipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Structural Classification of Neurons
- sensory neurons of the retina, olfactory mucosa,
and inner ear

A

Bipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Structural Classification of Neurons

- other sensory neurons, including the dorsal root ganglia & cranial ganglia

A

Uni/Pseudounipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Structural Classification of Neurons
- neurons of the CNS lack true axons and do not
produce action potentials, but regulate local electrical
changes of adjacent neurons

A

Anaxonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

– Carries material from the nerve cell body to the periphery
– Utilizes kinesin, microtubule-associated motor protein that uses ATP

A

Anterograde transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

– Carries material from the axon terminal & dendrites to the nerve cell body
– Utilizes dynein, microtubule-associated motor protein

A

Retrograde transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

conveys substances from the cell body to the terminal bouton at the speed of 0.2 to 4 mm/day

  • Anterograde only
  • Tubulin molecules, actin molecules, & neurofilament proteins
A

Slow Transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Conveys substances in both directions at a rate of 20 to 400 mm/day

  • Anterograde carries membrane-limited organelles, sER components, synaptic vesicles, & mitochondria
  • Retrograde carries membrane-limited organelles & molecules endocytosed at the axon terminal; path followed by toxins & viruses
A

Fast transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Functional Classification of Neurons
- (afferent) receive stimuli from receptors throughout
the body

A

Sensory neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Functional Classification of Neurons

- (efferent) send impulses to effector organs

A

Motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Functional Classification of Neurons

- neurons under voluntary control & innervate skeletal muscle (motor neurons)

A

Somatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Functional Classification of Neurons

- control the involuntary or unconscious activities of glands, cardiac muscle, & smooth muscle

A

Autonomic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Functional Classification of Neurons

  • establish relationships among other neurons, forming complex functional circuits
  • Comprise 99% of all neurons in adults
A

Interneurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  • Presynaptic terminal bouton contains mitochondria & synaptic vesicles → release NT via exocytosis
  • 20- to 30-nm-wide intercellular space, synaptic cleft separates pre- & postsynaptic membranes
  • Postsynaptic cell membrane contains:
  • Receptors for the neurotransmitter
  • Ion channels to initiate a new impulse
A

Chemical Synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

• Permit direct, passive flow of electrical current from one neuron
to another
- Potential difference generated locally
by presynaptic action potential

• Current flow occurs via gap junctions, link pre- & postsynaptic membranes (2nm)

• Contain connexon proteins, permit
diffusion of small molecules &
electric current flow (NO vesicles)

A

Electrical Synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

fibrous intercellular network of cellular processes emerging from neurons & glial cells

A

Neuropil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q
  • Large number of long, branching processes

* Proximal regions are reinforced with intermediate filaments made of glial fibrillary acid protein (GFAP)

25
• Processes can affect the formation, function, and plasticity of synapses • Regulate extracellular ionic concentrations around neurons, with particular importance in buffering extracellular ?levels • Guide and physically support movements & locations of differentiating neurons during CNS development • Extend fibrous processes with expanded ? that cover capillary endothelial cells and modulate blood flow and help move nutrients, wastes, and other metabolites between neurons and capillaries • Filling tissue defects after CNS injury by proliferation to form an ?
Astrocyte Functions - K+ - perivascular feet - astrocytic scar
26
• Extend many processes that wrap repeatedly around a portion of a nearby axon - Cytoplasm gradually moves out, leaving compacted layers of cell membrane, myelin • Will enwrap axons from multiple neurons • Usually appear as small cells with rounded, condensed nuclei & unstained cytoplasm
Oligodendrocytes
27
• Glial cells derived from neuroepithelium • Begins in lower brain stem, older tracts first • 6th months through puberty
CNS: oligodendrocytes
28
• NCC derived • Motor roots myelinated before sensory roots • 4th month
PNS: Schwann cells
29
• ? cells that line the fluid-filled ventricles of the brain & the central canal of the spinal cord • Apical end may have cilia & long microvilli - Facilitate movement of CSF - Likely involved in absorption • Joined apically by apical junctional complexes & there is no ?
Ependymal Cells - Columnar or cuboidal - basal lamina
30
• Elaborately folded & highly vascular tissue, found in the roofs of the ?, & in parts of ? • Contains a thin layer of well-vascularized pia mater covered by ? ependymal cells ``` • Removes H2O from blood & releases it as CSF – Contains ?, ?, & ? ions – Very little protein – Only cells include sparse lymphocytes ``` * Completely fills ventricles, central canal of SC, subarachnoid & perivascular spaces * ? provide absorption pathway for CSF back into the venous circulation
Choroid Plexus - 3rd & 4th ventricles - lateral ventricular walls - columnar to cuboidal - Na+, K+, & Cl- - Arachnoid villi
31
• Less numerous than oligodendrocytes or astrocytes • Migratory, will remove damaged or unactive synapses or other fibrous components • Major mechanism of immune defense in the CNS, removing any microbial invaders • Originate from monocytes
Microglia
32
Cerebellar Cortex | - has much neuropil & scattered neuronal cell bodies
Molecular Layer
33
Cerebellar Cortex - extend dendrites throughout the molecular layer as a branching basket of nerve fibers - Conspicuous in H&E-stained sections
Purkinje Cells
34
Cerebellar Cortex - contains various very small, densely packed neurons (i.e., granule cells) & little neuropil
Granular layer
35
Cerebellar Cortex | - Organized into folia with the ? located deep
cerebellar medulla
36
Cerebral Cortex | - Biologically older parts of the cortex are arranged into three layers
Archicortex
37
Cerebral Cortex - Most of the cortex (~90%) - Consists of 6 layers
Neocortex
38
Cerebral Cortex - pyramid-shaped cell bodies with the apex directed towards the cortical surface - Huge upper motor neurons of the motor cortex (Betz cells), are the largest of these cells
Pyramidal Cells
39
Cerebral Cortex | - small neurons with a cell body the shape of a star (look like granules in micrographs)
Granule (stellate) cells
40
Cerebral Cortex | - Small polygonal cells with a few short dendrites
Cells of Martinotti
41
Cerebral Cortex - Spindle-shaped cells oriented at right angles to the surface of the cerebral cortex
Fusiform cells
42
Cerebral Cortex | - small & spindle-shaped but oriented parallel to the surface (least common)
Horizontal cells of Cajal
43
Cortical Layers - consists largely of fibers, most of which travel parallel to the surface, & mostly neuroglial cells & horizontal cells of Cajal
Plexiform Layer (or molecular layer)
44
Cortical Layers | - consists mainly of small pyramidal cells & granule cells
Small Pyramidal Cell Layer (or outer granular layer)
45
Cortical Layers | - pyramidal cells are somewhat larger and possess a typical pyramidal shape; not sharply demarcated from layer II
Layer of Medium Pyramidal Cells (or layer of outer pyramidal cells)
46
Cortical Layers | - is characterized by the presence of many small granule cells
Granular Layer (or inner granular layer)
47
Cortical Layers | - contains pyramidal cells are extremely large (Betz cells) in motor areas
Large Pyramidal Cell Layer (or inner layer of pyramidal cells)
48
Cortical Layers | - contains cells with diverse shapes, many are fusiform cells
Polymorphic Layer
49
• Function in the "limbic system“ • Integrates inputs various cortical areas into complicated behaviors - Learning, memory, & social interaction • Morphologically is considered ?, - Comprised of three layers (rather the six layers found in the cerebral cortex)
The Hippocampus & Dentate Gyrus - archicortex
50
Hippocampus Layer: | - nerve fibers & small cell bodies of interneurons
Polymorphic layer
51
Hippocampus Layer: | - hippocampal pyramidal cells
Middle pyramidal cell layer
52
Hippocampus Layer: | - Dendrites of the pyramidal cells
Molecular layer
53
Dentate gyrus Layer: | - Nerve fibers (known as "mossy fibers") & cell bodies of interneurons
Polymorphic layer
54
Dentate gyrus Layer: | - Round, neuronal cell bodies of dentate granule cells
Middle granule cell layer
55
Dentate gyrus Layer: | - Containing dendrites of the granule cells
Molecular Layer
56
The region where the head of hippocampus abuts the dentate gyrus
hilus
57
• Most common neurodegenerative disease, incidence increases with age - Typical presentation is 70+ years • Symptoms: - Memory failure, progressing steadily to involve motor skills, speech & sensation • Etiology is unknown, small proportion of cases have a genetic association • Striking thinning of gyri, particularly those of the ? and ? lobes
Alzheimer's disease - frontal and temporal
58
Alzheimer's disease - amorphous, pink masses in the cortex
Amyloid (amyloid β) plaques
59
Alzheimer's disease | - flame-shaped skeins formed by abnormal accumulation of tau
Neurofibrillary tangles

Neuroscience (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions