Nervous system and special senses Flashcards
which 2 system comprise the CNS
brain and spinal cord
what does the peripheral nervous system do ?
enervate the body
arise from the cranial and spinal nerves
what is the function of blood brain barrier
comprised of astrocytes wrapping around the capillaries
ensures brain is immunologically privileged
prevents admission of some therapeutic compounds
what is the importance of myelin
allow for saltatory conduction
lipid rich substance which envelopes certain neurones
Multiple sclerosis
Chronic inflammatory condition that affect the brain and spinal cord
what are the factor that can contribute to MS
highest in temperate climatic zones
more common in Caucasians
women are 2x more likely to develop MS than men
HLA-DR15
what is vitamin D known for
modulate the immune response
clinical manifestation of MS
inflammatory response it depends on which region of CNS that lesion occurs in: - corticospinal ms - spinal ms - cerebellar MS
causes of MS
autoreactive immune cells target myelin antigens and destroy them
causing the neurones to apoptose
what diagnosis is used in the multiple sclerosis
McDonald criteria
what is Guillain - Barre syndrome
acute disorder of the peripheral nerves that causes weakness and paralysis in the limbs
causes of guillain - barre syndrome
associated with infection
commonly from the campylobacter jejuni
how many neurotransmitters is known of atm
46
what is Parkinson’s diseases
a complex motor disorder that leads patients to have bradykinesia, postural abnormalities, tremor & rigidity
causing movement-related deficit
function of dopamine
essential neurotransmitter for motor control
what specialised cells produces dopamine in the brain
substantia nigra
what does dopamine do in the brain?
associated with feelings of rewards, motivation and being productive
what could lead to loss of dopamine in PD?
the interactivity of the direct motor pathway
overactivity of the indirect motor pathway
cognitive symptoms
what causes the loss of dopaminergic nerurones
mitochondrial dysfunciton
oxidative stress
inflammation
how L-Dopa treat PD?
precursor for dopamine
could convert into dopamine by DOPA
what can you used to classified PD’s severity?
Hoehn and Yahr scale
what are the special senses
sight
hearing
taste
smell
what are the responsible for rods and cones in the eye
rods - responsible for peripheral vision and dim-light
Cones - colour and detail receptors
what is accommodation in terms of the eye
ability of the eye to change its focus
what muscles allow lens to change its shape
ciliary muscle
define these terms
- Myopia
- Hyperopia
Myopia ==> short sightedness
Hyperopia ==> long sightedness
what causes accommodation disorders
ciliary muscle disease
astigmatism (blurry vision / 散光)
what is cataracts
cloudy or opaque area in the ocular lens
causing blindness
common associated with cataracts
changes in the metabolism of cells
changes in fluid transport
increase in age
what does retina do ?
converts light into an electrical signal
how many layers does human retina has and what are they
neural tissue
photoreceptors
supporting tissues
what are the 2 main forms of photoreceptors
cone cells
rod cells
what is rhodopsin
main photoreceptor and is made of 2 components:
- opsin
- retinal
explain opsin and retinal
opsin - transmembrane protein
a compound which can absorb light
what are the 3 types of cone cells in the retina
S cone
M cone
L cone
what does the suprachiasmatic nucleus regulates
circadian rhythms in the body
where is suprachiasmatic nucleus located
anterior part of the hypothalamus
what does superior colliculus does
incorporating environmental stimuli and coordinating gaze shift involving both eye and head movement
- receiving signal from the responsive movements*
