Loading...
Question 1
What are the two main components of the nervous system?
Central Nervous System (CNS) and Peripheral Nervous System (PNS)
Question 2
What is the Central Nervous System (CNS) composed of?
Brain and spinal cord
Question 3
What are the two divisions of the Peripheral Nervous System (PNS)?
Autonomic and Somatic
Question 4
What are the three main types of cells in the nervous system?
Neurons, interneurons, and glial cells
Question 5
What is the difference between a nucleus and a ganglion?
nucleus: cluster of neural cell bodies in CNS ganglion: group of neural cell bodies outside the CNS
Question 6
What layer does the nervous system start developing from
ectoderm
Question 7
What is the neural plate and what does it develop into?
thickened region of ectoderm → develops into neural tube and neural crest
Question 8
What are the anterior and posterior ends of the neural tube responsible for developing?
Anterior: brain structures Posterior: spinal cord
Question 9
What do neural tube cells become
giver ise to neurons and glia in CNS
Question 10
What are neural tube defects?
Congenital malformations of the nervous system
Question 11
What is anencephaly?
- severe neural tube defect - failure of closure of the anterior neural tube - absence of the brain and skull bones - infants dying shortly after birth
Question 12
What is Spina bifida?
defective closure of the posterior neuropore
Question 13
What are the subtypes of Spina bifida according to severity?
Spina bifida occulta and severe cases.
Question 14
What is Spina bifida occulta?
mild, asymptomatic form where one or more vertebrae don't fully close, but the spinal cord is undamaged
Question 15
What is the primary source of blood supply to the brain?
The Circle of Willis
Question 16
Which arteries form the Circle of Willis?
- Anterior communicating artery - posterior communicating artery - two posterior cerebral arteries
Question 17
What percentage of daily cardiac output does the brain receive?
15%
Question 18
What are the two main arteries that supply blood to the anterior part of the brain?
Anterior carotid arteries
Question 19
Which pair of arteries supplies blood to the posterior part of the brain?
Vertebral arteries
Question 20
Through which vein does venous drainage from the brain occur?
Internal Jugular vein
Question 21
What is the function of the cell body in a neuron?
- contains the nucleus and other organelles - genetic and metabolic center of the neuron
Question 22
What are dendrites and what do they do?
Dendrites receive stimuli or input via chemoreceptors.
Question 23
What is the definition of a multipolar neuron?
multiple dendrites originating from the cell soma and a single axon
Question 24
What are the examples of neurons that are multipolar?
CNS and somatic NS.
Question 25
What is the definition of a bipolar neuron?
2 processes that extend from opposite sides of a round or oval-shaped cell body
Question 26
What is a pseudounipolar neuron
1 process that bifurcates shortly after leaving the soma e.g sensory neurons of PNS
Question 27
What is the largest diameter and fastest conduction velocity for myelinated nerve fibers?
A-alpha A-beta A-gamma A-delta B
Question 28
Which fiber is unmylinated
C
Question 29
Pattern between type of fiber vs diameter vs conduction velocity
myelinated - bigger - faster unmyelinated - smaller - slower
Question 30
What is the function of sensory neurons?
- afferent - receive stimuli from internal and external environments - conduct impulses towards the CNS for processing and analysis
Question 31
What is the function of motor neurons?
- efferent - conduct impulses from the CNS towards effector tissues - responsible for 'action'
Question 32
What is the role of interneurons?
connect sensory and motor neurons regulate the signals transmitted between neurons
Question 33
What is the primary function of glial cells?
To support neuronal function and survival
Question 34
What are the two main types of glial cells classified into?
Microglia and macroglia
Question 35
What type of glial cells does the CNS have
• oligodendrocytes • astrocytes • ependymal cells • microglial cells
Question 36
What type of glial cells does the PNS have
• Schwann cells • satellite cells
Question 37
What are Microglia
immune cells of the CNS
- from monocytes - tissue-resident macrophages - branched processes for motion between grey and white matter
Question 38
Microglia function
Immune defense mechanism - removing cellular debris from injury, infection, and disease - phagocytosis - secreting immunoregulatory factors
Question 39
What are the types of macroglia
• astrocytes • ependymal cells • oligodendrocytes • Schwann cells • Satellite cells
Question 40
What is the most common type of glial cell in the CNS and what protein does it produce?
Astrocytes produce GFAP (glial fibrillary acid protein).
Question 41
What are the functions of astrocytes?
• Scaffold for neural migration • synaptic transmission • neural protection • BBB formation; astrocyte end feet • nutrient transfer; blood → neurons
Question 42
What is the function of ependymal cells in the central nervous system (CNS)?
Produce cerebrospinal fluid
• cilia to facilitate CSF movement • microvilli to help with CSF absorption
Question 43
Where are oligodendrocytes foud
only in CNS
Question 44
What is the function of oligodendrocytes
Produce myelin sheath for neural axons in CNS
Question 45
What is the myelin sheath
• fatty layer that electrically insulates the axon • facilitates rapid transmission of nerve impulses
Question 46
What are Schwann cells
• found in the PNS • produce myelin sheath
Question 47
What are satellite cells
• found in PNS • functions for electricity insulation and nutrient/waste exchange along ganglia
Question 48
What is the difference between grey matter and white matter in the brain?
Grey: consists of neuron cell bodies, dendrites, astrocytes, and microglial cells White: lipid-rich myelin sheaths surrounding axons
Question 49
What are the three main parts of the brain?
Forebrain, midbrain, hindbrain
Question 50
What are the two parts of the forebrain?
Telencephalon - cerebrum Diencephalon - thalamus, pineal gland, posterior pituitary gland
Question 51
What structures are found in the midbrain?
• Superior and inferior colliculi • cerebral peduncle • substantia nigra
Question 52
What structures make up the hindbrain
• pons • medulla • cerebellum
Question 53
What are the three main components of the cerebrum?
• Cortex • cerebral white matter • subcortical structures (basal ganglia, hippocampus)
Question 54
What is the cerebral cortex?
The outer layer of the cerebrum.
Question 55
What is the Brodmann classification?
A classification that divides the cerebral cortex into 52 regions based on neural shapes and arrangement.
Question 56
What is the frontal lobe responsible for?
• prefrontal cortex: judgment, reasoning, and social behavior • primary motor cortex
Question 57
What is the function of the parietal lobe?
primary sensory cortex
• integration of sensory input and attention
Question 58
Where is the occipital lobe located?
primary visual cortex
Question 59
What are the functions of the temporal lobe?
Auditory processing, language recognition, and formation of new and long-term memories.
Question 60
What is the function of the corpus callosum?
• Interconnects left and right hemispheres • allowing hemispheres to communicate
Question 61
What are projection fibers and what do they connect?
Connect the cerebral cortex with lower portions of the brain or the spinal cord • enabling cortex to receive or transmit signals
Question 62
What is the role of association fibers in the brain?
• connect various regions within the same hemisphere • permit cortex to function as a coordinated unit
Question 63
List the main structures of the basal ganglia.
Striatum (caudate nucleus and putamen), globus pallidus, substantia nigra
Question 64
What is the function of the basal ganglia?
Responsible for thalamus-cortical neural signaling
Question 65
What are the functions of the basal ganglia in the brain?
• fine motor movement • cognition and decision-making • motivation and brain reward system
Question 66
What disease is associated with lesions in the striatum?
Huntington disease
Question 67
What are the main components of the diencephalon?
thalamus, hypothalamus, pineal gland, and the posterior part of the pituitary gland
Question 68
What is the thalamus and where is it located?
• relay station that relays sensory and motor signals to the cerebral cortex • in both hemispheres and surrounds the third ventricle
Question 69
What are the functions of the thalamus?
• relay station • regulates cortical activation, memory, and visual input
Question 70
What are the main functions of the hypothalamus?
• maintenance of homeostasis and emotional control • endocrine control - hypothalamic-hypophyseal system • regulation of temperature by
inducing shivering
• regulation of food intake
Question 71
What are thermoreceptors and what do they do?
• provide temperature information to the preoptic area in the hypothalamus • maintain a constant core body temperature
Question 72
What are the mechanisms the hypothalamus uses to increase heat production?
• increased metabolism via the thyroid gland • shivering • inhibiting sweating • promoting vasoconstriction to reduce heat loss through skin
Question 73
Mechanisms anterior hypothalamus uses to enable heat loss
• Vasodilation of skin blood vessels • sweating • decrease in heat production
Question 74
What are pyrogens and how do they contribute to fever?
•substances from infections • trigger the production of IL-1 and increase PG E2 • reduces the activity of preoptic nuclei and anterior hypothalamus • changing the body's temperature set point
Question 75
What is the role of PGE2 in fever?
reduces the activity of preoptic nuclei and anterior hypothalamus → preventing heat dissipation
Question 76
What does substantia nigra contain
dopamine-producing neurons
Question 77
What are the components of the Hindbrain?
pons, medulla oblongata, and cerebellum
Question 78
What does brainstem consist of?
midbrain, pons, and medulla oblongata
Question 79
function of the pons
• relays sensory info between cerebrum and spinal cord • contains nerve nuclei for sensation, eye movement, and auditory functions • regulates the arousal/sleep cycle
Question 80
medulla function
•
reflex center for cardiovascular and respiratory control
• contains ascending and descending fiber tracts connecting the brainstem to the spinal cord • responsible for the vomiting reflex
Question 81
where is the cerebellum located?
posterior cranial fossa behind the pons and medulla
Question 82
What are the two hemispheres of the cerebellum separated by?
a narrow ridge called the vermis
Question 83
What are the three layers of the cerebellar cortex?
Molecular layer, Purkinje cell layer, and granular layer
Question 84
What neurotransmitter is responsible for the inhibitory output of the cerebellum?
Gamma-aminobutyric acid (GABA)
Question 85
What is the function of the Purkinje cell layer in the cerebellum?
It is responsible for the inhibitory output of the cerebellum.
Question 86
Functions of the cerebellum
• Anterior lobe: regulation of muscle tone • Posterior lobe: planning fine motor movements & coordinate motor function • Flocculonodular lobe: maintenance of posture/balance • dysfunction = hypotonia and ataxia
Question 87
What are the three main types of ataxia?
Cerebellar, sensory, and vestibular.
Question 88
What is cerebellar ataxia
• Caused by cerebellar degeneration • genetic cause: Friedreich's Ataxia, Ataxia Telangiectasia
Question 89
What is Friedreich's Ataxia and how is it inherited?
It is an autosomal recessive disorder caused by a mutation of the frataxin gene.
Question 90
What gene is defective in Ataxia Telangiectasia and what are some of its symptoms?
The ATM gene is defective • cerebellar atrophy • immune deficiency • children: high risk of cancer • DNA highly sensitive to ionizing radiation
Question 91
What are the four ventricles of the brain?
Two lateral ventricles, one third ventricle, and one fourth ventricle.
Question 92
What is the function of the ventricular system in the brain?
production + circulation of CSF
Question 93
What is the Foramen of Monro and how does it relate to the ventricular system?
connects the lateral ventricles with the third ventricle
Question 94
How do the 3rd and 4th ventricle communicate
cerebral aqueduct
Question 95
What is hydrocephalus?
A condition characterized by an abnormal accumulation of cerebrospinal fluid in the ventricles of the brain, leading to ventricular dilatation.
Question 96
What are the causes of hydrocephalus?
Excessive cerebrospinal fluid production • impaired absorption of cerebrospinal fluid • or obstructions within the ventricular system
Question 97
What is hydrocephalus in children?
Enlargement of the head due to the skull bones not being completely fused
Question 98
What are the symptoms of hydrocephalus in children?
changes in tooth eruption patterns higher plaque accumulation higher caries prevalence.
Question 99
What is a ventriculoperitoneal shunt?
device used to drain excess CSF from brain into the abdominal cavity or atrium
Question 100
What are some dental modifications for patients with a VA shunt?
chair positioning avoiding excessive force to the catheter possible antibiotic prophylaxis shorter appointments