Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chika- SF2 > History of Nervous System- Heinbockel > Flashcards

History of Nervous System- Heinbockel Flashcards

1
Q

What are the different neuronal types?

A
  • sensory neuron (pseudounipolar)
  • motor neuron
  • local interneuron
  • projection interneuron
  • neuroendocrine cell
  • model neuron
  • signal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are two kinds of glia? What are examples of each type?

A

Microglia:
-microglia (phagocytic)

Macroglia:

  1. Myelin-forming cells
    - oligodendrocytes (CNS)
    - schwann cell (PNS)
  2. “Supporting”cells
    - astrocytes (CNS)
    - satellite cells (PNS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the function of microglia?

A
  • invade brain during fetal development and maintain residence in parenchyma
  • responsible for response to injury to trauma in brain by proliferation and phagocytosis of debris
  • spider-like cells

-have a protective, phagocytic, immune-related function

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

What is the function of astrocytes?

A
  • convert to different shapes, developing on function
  • intimate associations with blood vessels, ventricles, neurons, synaptic terminal zones
  • processes extend around terminal which may serve to control diffusion of released neurotransmitters
  • store, buffer, and release ions, transmitters; have receptors, and some even form synapses
  • communicate with each other, and with neurons, via gap-junctions
  • high producers of cytokines that “nurse” cells

-have multiple processes and form perivascular feet that COMPLETELY ENCLOSE all capillaries (only a few such feet are shown here to allow their morphology to be seen)

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

What is the function of schwann cells?

A
  • derived from neural crest
  • serve as support cells and myelinating cells of the PNS
  • can act as macrophages and produce cytokines
  • also called neurolemmocytes that form a series of ensheathing axons
  • one cell per axon, but can cover unmyelinated axons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the function of oligodendrocytes?

A
  • myelinates parts of several axons in the CNS

- ONE cell wraps several axons

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

What are the four major glia in the CNS?

A

Astrocytes, oligodendrocytes, microglia, and ependymal cells

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

What are the two major glia in the PNS?

A

Schwann cells and satellite cells

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

Describe ependymal cells.

A
  • cuboidal or columnar epithelial-like cells that line the ventricles and central canal of CNS
  • remnants of embryonic neuroepithelium
  • microvilli and cilia on luminal surface helps move CSF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the function of satellite cells?

A
  • are involved in metabolism, ion, and transmitter balance, etc.
  • are restricted to ganglis where they cover and support the large neuronal cell bodies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which glia in the CNS mediates response to injury by proliferating, migrating to site of injury, and removing debris by phagocytosis?

A

microglia

  • microglia are small cells with delicate processes, inconspicuous in H&E stained section
  • migrate actively
  • important in neuropathology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are microglia derived from?

A

-derived from monocytes incorporated into CNS during development

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

Which glia in the CNS is the interface between neurons, pia, ependyma, and blood vessels and guide axons during development (radial glia)?

A

astrocytes

  • astrocytes provide structural support
  • take up neurotransmitters
  • regulate ionic balance
  • involved in immune response
  • form glial scars after CNS injury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When an individual has spinal cord injury, the neuron that is damaged changes its morphology and form. So a presynaptic terminal might actually retract from the damaged neuron. This glia cell would then form a scar around the axon terminal so the presynaptic terminals will not form a functional synapse to damaged post-synaptic neuron.

A

astrocytes

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

Where do astrocytes form end feet?

A
  • on the pia mater (basal lamina of the external limiting membrane)
  • on the endothelial cells of the capillaries (perivascular limiting membrane)
  • on the ependymal cells that line the ventricles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the meninges? Which meninge is composed of loose connective tissue, closest to the brain and spinal cord and consisted of lots of blood vessels?

A

From outside to the inside:

  • Dura mater
  • arachnoid mater
  • pia mater

Pia mater is composed of loose connective tissue, closest to the brain and spinal cord and consisted of lots of blood vessels.

-these blood vessels are initially covered with pia mater, but as capillaries they are covered only by the perivascular feet of astrocytes

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

What is multiple sclerosis?

A

a demyelination disease in the CNS

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

What is critical for impulse conduction in axons?

A

myelin

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

What produces the myelin in a motor neuron?

A

myelin sheath is produced by oligodendrocytes in the CNS and by schwann cells in the PNS

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

The neuronal cell body of a motor neuron, has unusually large ______nucleus with a well-developed nucleolus. The perikaryon contains____________,which are also found in large dendrites.

A

euchromatc

Nissl bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The spinal cord has what two major types of tissue and what do they each contain?

A

gray matter
-contains the nerve cell bodies and all of the many thousands of connections between nerves, dendrites, axon terminals, bundles of UNmyelinated axons and neuroglia

white matter
-composed of nerve axon fibers traveling long distances from spine to the brain

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

The________carries motor axon fibers from cells in the gray matter out to the muscles. Incoming sensory signals pass through a connection or synapse in the ____________, and then follow out the dorsal root into the gray matter.

A

ventral root

dorsal root ganglion

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

How is the gray matter shaped in the spinal cord compared to the brain?

A
  • spinal cord: gray matter forms an H-shaped inner core surrounded by white matter
  • brain: a thin outer shell of gray matter covers the surface and is found in clusters called nuclei inside the CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a groups of cell bodies (neuronal aggregates) called in the CNS and PNS?

A

CNS: nucleus
PNS: ganglion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the functional division of the peripheral nervous system?

A
  • somatic nervous system

- autonomic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the function of the somatic nervous system?

A

voluntary motor and sensory components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the function of the autonomic nervous system?

A
  • involuntary control of viscera

- sympathetic system “fight-or-flight”; thoraco-lumbar parasympathetic system; “steady-state”; cranio-sacral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the distinct difference of motor neurons in the somatic and autonomic nervous system? What about sensory neurons?

A

somatic:
-motor neurons have their cell bodies in the ventral horn and they leave the spinal cord and synapse directly onto the skeletal muscle fiber

autonomic:
-pre-ganglionic neuron synapse onto the autonomic ganglion and the post-ganglionic neuron synapses on the smooth or cardiac muscle, or glands for secretion

Sensory neurons come directly from the receptors into the CNS and on the way back there is NO ganglion in between for BOTH somatic and autonomic nervous system

29
Q

The brain is protected from injury by what?

A

the skull, meninges, CSF, and blood-brain barrier

30
Q

What is the function of the meninges?

A

to cover and protect the brain itself; it encloses and protects the vessels that supply the brain and contains CSF between the pia and arachnoid mater

31
Q

What is deep to the periosteum that creates the dura mater?

A

periosteal and meningeal

  • dura mater is found all around the brain and its 2 layers separate and create spaces called dural sinuses
  • the meningal separates from the periosteal and goes down into the longitudinal fissure; the space that is formed is a sinus
32
Q

Deep to the dura mater is the POTENTIAL subdural space and deep to that is the POTENTIAL subarachnoid space. Why are these potential spaces?

A

subdural space is an artifact created by separation of the dura from the underlying tissue

subarachnoid space is filled with CSF and the arachnoid acts as a shock absorbing pad between the CNS and bone

33
Q

This protrudes from the arachnoid mater (thin second layer) and allows CSF to exit the brain and pass into blood.

A

arachnoid villi (villus for singular)

  • are outpocketings of arachnoid mater away from the brain, which penetrate the dura mater and enter blood-filled venous sinuses located within that layer
  • they function to release excess CSF into the blood
34
Q

The continuation of the meningeal becomes the ________ and is ONLY found in the longitudinal fissure. It is the fusion of the meningeal layers of the dura mater below the superior sagittal sinus.

A

falx cerbri

35
Q

What is the largest dural sinus filled with blood?

A

superior sagittal sinus

36
Q

What is the falx cerebelli (do not confuse with falx cereBRI)?

A

a small triangular process of dura mater that is received into the posterior cerebellar notch and thus runs along the vermis (the rounded and elongated central part of the cerebellum), between the two hemisphere

37
Q

What is the tentorium cerebelli?

A

AKA tent of the cerebellum which lies in the transverse fissure and is horizontally oriented extension of the dura mate

  • it separates the cerebellum from the inferior portion of the occipital lobe
  • underneath the occipital lobe is the straight sinus
38
Q

The spinal cord has three meningeal layers of connective tissue: the innermost pia mater, the arachnoid, and dura mater. Blood vessels course through the subarachnoid space and the nerve rootlets that fuse to form the posterior (dorsal) root ganglia contain what and where are they located?

A

contain the cell bodies of the sensory nerve fibers and are located in the intervertebral foramina

39
Q

Surrounding the dura mater is the epidural space that contains what?

A

contains cushioning adipose tissue and vascular plexuses

40
Q

These glial cells of the CNS are important in forming the blood brain barrier.

A

astrocytes have end-feet on the capillaries in the brain

-

41
Q

What are the endothelial cells of the brain connected by?

A

TIGHT junctions

-there is relatively little movement across endothelial cells for any kind of molecule; it is a selective barrier

42
Q

What are the most abundant glial cells of the CNS characterized by numerous cytoplasmic processes radiating from the glial cell body or soma?

A

astrocytes

  • Astrocytes are an important part of the blood-brain barrier (BBB), regulating entry of molecules and ions from blood into CNS tissue.
  • capillaries are enclosed by GFAP-positive perivascular feet (PF) at the ends of numerous astrocytic processes
43
Q

Astrocyte process are seen with routine light microscope. True or false?

A

FALSE

they are easily seen after gold staining

44
Q

All astrocytic processes contain what intermediate filament for which antibodies provide a simple method to stain astrocytes?

A

Glial fibrillary acidic protein (GFAP)

45
Q

What is the difference between capillaries in general and capillaries in the brain?

A

capillaries in general

  • fenestration with intact basal membrane ( all the endocrine organ make hormones that get into the bloodstream through fenestra)
  • transport vesicles in the the endothelium
  • types of capillaries: fenestrated, sinusoids (spleen, liver), continuous

capillaries in the brain

  • no space between endothelial cells (tight junctions); so very few molecules can get across transport
  • pericytes
  • completely surrounded by astrocytic end feet
  • capillaries in the CNS for a protective barrier that restricts the exchange of soluble material between the blood and the brain
  • we need a constant intracerebral meilleur (brain needs a certain ion concentration critical for neuronal activity)
46
Q

What creates a selective and dynamic blood brain barrier (BBB)?

A
  • BBB is consisted of the endothelial cells, pericytes (muscular cells), and astrocytes, and a basement
  • when the BBB gets damaged you get edema, fluid that accumulates in CNS leading to neurological impairment
47
Q

What are the types of blood-brain barrier?

A
  1. Blood-ECF barrier
    - in the CNS capillary bed
  2. Blood-CSF barrier
    - in the choroid plexus
    - made up of capillaries covered by pia mater, ependyma (tela choroidea)

ependymal cells are modified:

  • cilia are replaced by microvilli and they have numerous enzymes specifically involved in the active transport of ions and metabolites
  • there is a basement membrane beneath the epithelium
  • tight junctions are present between the ependymal cells at the apices
48
Q

Describe the endothelial cells of the brain.

A
  • joined by tight junctions of high electrical resistance provided an effective barrier against molecules
  • brain capillaries are in contact with foot processes of astrocytes, which essentially separate the capillaries from the neurons

In peripheral endothelial cells there is good transcellular movement of molecules. However in the brain there is no such movement in brain endothelial cells

49
Q

Why is the blood brain barrier not an absolute barrier?

A
  • because fat soluble molecules can easily pass such as alcohol, nicotine, and anesthetics
  • the cell’s plasma membrane is made of phospholipids and so anything that is fat soluble (nonpolar) can still pass through

The BBB protects the brain from within: this is the final layer of protection in the brain. The flattened endothelial cells have the least permeable capillaries in the entire body due to the tight junctions which literally sew the cell membranes together and prevent blood-borne toxins from entering the brain but it’s still not an absolute barrier as discussed above

50
Q

What are the pathways across the blood-brain barrier?

A

a. paracellular aqueous pathway: water soluble agents
b. transcellular lipophilic pathway: lipid soluble agent
c. transport proteins: glucose(GLUT1; reduced in Alzheimer’s pts), amino acids, nucleotides (dopamine in Parkinson’s dz)
d. receptor-mediated transcytosis: insulin, transferrin
e. adsorptive transcytosis: albumin, other plasma proteins

51
Q

What is the function of the choroid plexus of the ventricular system?

A
  • produces CSF
  • consists of ependyma and vascularized pia mater and projects many thin folds from certain walls of the ventricles
  • well vascularized with large capillaries and covered by a continuous layer of cuboidal ependymal cells
  • specialized for transport of water and ions across the capillary endothelium and ependymal layer and the elaboration of these as CSF
  • the ventricular system is normally filled with CSF
52
Q

Describe the filtration system of the choroid plexus.

A

The choroid plexuses are composed of ependymal cells and capillaries that are attached to pia mater and create CSF.

  • the cilia from the choroid plexuses stick out into the space in the ventricles
  • underneath the ependymal cells are capillaries
  • blood plasma diffuses out the capillaries and moves into the ependymal cells
  • once blood plasma diffuses out the capillaries and move into the ependymal cells it is called CSF
  • CSF forms as a filtrate containing glucose, oxygen, vitamins, and ions (Na+, Cl-, Mg2+, etc.)
  • when things go in the other direction, ependymal cells absorb waste

about 500mL per day circulates everyday from blood to CSF and then back to blood

53
Q

What is the difference between plasma blood and CSF?

A

CSF has significantly lower amount of protein.

CSF contains glucose, oxygen, vitamins, and ions

54
Q

What are examples of material the BBB is permeable and NOT permeable to?

A

freely permeable to water
permeable to:
-non-ionised lipid soluble substances (ethanol and caffeine)

Not permeable to

  • protein
  • protein-bound substances (drugs, hormones)
  • strongly hydrophilic (water soluble) substances (Na, K)
  • use of specialised carrier-mediated transport mechanisms
55
Q

Apart from the choroid plexuses, CSF can come into contact with ECF of brain tissue where?

A
  • ependymal cell-ECF surface

- subarachnoid space-ECF interface

56
Q

The ECF as far as the volume is concerned is what percentage of total brain volume?

A

15%

57
Q

What is the flow of CSF?

A
  • CSF is produced by the choroid plexus of each ventricle.
  • CSF flows through the ventricles and into the subarachnoid space via the median and lateral apertures (Magendie and Luschka). Some CSF flows through the central canal of the spinal cord.
  • CSF flows through the subarachnoid space
  • CSF is absorbed into the dural venous sinuses via the arachnoid villi
58
Q

What is the CSF pathway from lateral ventricles to the subarachnoid space?

A

lateral ventricle
—> interventricular foramine (foramen of Monroe) —>3rd ventricle—> supraoptic recess of 3rd ventricle –> infundibular recess of 3rd ventricle—> cerebral aqueduct—> 4th ventricle—> foramen of Luschka (lateral) and Magendie (medial)—> subarachnoid space

59
Q

What are circumventricular organs (CVO)?

A

-structures that permit polypeptide hypothalamic hormones to leave the brain without disrupting the BBB and permit substances that do not cross the BBB to trigger changes in brain function

60
Q

Circumventricular organs (CVO) can be classified into sensory and secretory organs. Describe both.

A

sensory organs: include the area postrema (AP), the subformical organ (SFO)and the organum vasculosum of lamina terminalis (OVLT)

secretory organs: include the subcommissural organ (SCO), the posterior pituitary (ie. neurohypophysis), the pineal gland, the median eminence, and the intermediate lobe of the pituitary

61
Q

What are the 7 circumventricular organs?

A
  • pineal gland
  • area postrema
  • neurohypophysis
  • organum vasculosum
  • subfornical organ
  • subcommissural organ
  • median eminence of third ventricle
62
Q

What is the function of the pineal gland?

A

mediate circadian rhythms (melatonin)

63
Q

What is the function of area postrema?

A

body fluid homeostasis, emetic physiology (inducing vomiting)

64
Q

What is the function of neurohypophysis?

A

(posterior pituitary) stimulates H2O retention and contraction of blood vessels to increase BP

65
Q

What is the function of organum vasculosum?

A

fluid and electrolyte balance

66
Q

What is the function of subfornical organ?

A

thirst regulating

67
Q

What is the function of subcommissural organ?

A

secrete various glycoproteins into CSF

68
Q

What is the function of median eminence of 3rd ventricle (floor)?

A

hypophysiotropic hormones converge before they are conveyed to the pituitary gland (neurohypophysis)

Chika- SF2 (63 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions