LOCO EOYS5 Flashcards
explain mechanism of docking at NMJ and release of Ach occurs at presynaptic vesicle
vesicles docks by:
- synaptobrevin interacts with syntaxin and SNAP25: holds the vesicle close to pre-synaptic membrane (but doesnt fuse) = docking.
- Ca2+ binds to synaptotagmin: interacts with SNAP25/ syntaxin complex and tightens interaction between the vesicle and presynaptic membrane complexs & causes it to merge & release of Ach = confirmational change occurs.
what is scissor gait:
•Thigh swings across body during swing phase
•Difficulty in putting heel on ground
–Toe walking
–Unstable
what is the cubital fossa’s boundaries? [3]
what is nicotinic Ach receptor structure like? [2]
how many Ach have to bind before the Ach-receptor opens? [2]
what is an end plate potential? [1]
at what point does an AP occur in muscle? [1]
what is nicotinic Ach receptor structure like? [2]
- 5 subunits: 2 identical alpha subunits, 1 beta, 1 delta (& 1 gamma or epsilon)
how many Ach have to bind before the Ach-receptor opens? [2]
2
what is an end plate potential? [1]
when Na+ move into the muscle & cause depol
at what point does an AP occur in muscle? [1]
- 40mV
what happens after Ach binds to Ach receptor?
- Ach binds to Ach-receptor
- opens Ach-receptor
- allows Na channel to open & Na goes through
- causes depolarisation of muscle membrane
- causes release of Calcium from sarcoplasmic reciticulum
… other steps… - muscle contraction
which is this muscle?
innervation?
movement [2]
which is this muscle: sartorius
innervation: femoral nerve
movement [2]: flexes hip AND knee
what are the two types of NMJ blockers [2] explain them
What are the two types of NMJ blockers [2]:
1. D tubocuraine: non-depolarising muscle relaxant
blocks the nicotonic Ach-R & prevents AP occuring
- Acetylcholinesterase inhibitor works as an antidote to it
- *2. depolarisng muscle relaxant**
- stimulate Ach-R like Ach and activate muscle (muscle twitch)
- but **do not detach: no more Ach can bind (paralysis)
- even if membrane is repolarised (from Na channels / NaKATPase), the drug causes it to bedesensitised**
- but breaks down after a while, so not perm. paraylses
how does is weight distributed in after going through verterbral body? [3]
what specifically enables use to undetake bipedal standing & walking more efficient? [1]
how does is weight distributed in after going through verterbral body?
•Weight of upper body transmitted centrally through vertebral column (1)
•Ilium transfers weight to femurs (2-3)
•Pubic rami form ‘struts’ or braces that maintain integrity of arch (4)
what specifically enables use to undetake bipedal standing & walking more efficient? [1]
Diagonal angle of femurs re-centres support directly under the body to make bipedal standing more efficient and to help walking. Quadripeds require simultaneous support from both sides.
when conducting a gait analysis, what do u look for? [5]
Gait analysis:
Balance
Co-ordination
Walking rhythm
Change of speed/direction
Stride length
what is the order of neurovasculature of femoral things? [3]
femoral artery = pulsating just belowing midinguinal point
femoral nerve = lateral to artery
femoral vein = medial
VAN
what does quantal release of Ach mean? [1]
every vesicle contains same amount of ACh: same amount of NM is released with each AP. get a 1:1 transmission of nerve & muscle.
what is high stepping gait characterised by? [2]
which nerve damage causes this? [1]
- dorsiflexor paraylsis - foot drop (unless leg is lifted higher by exaggerated knee bend)
- common peroneal nerve injury
- whole foot tends to be slapped on ground rather than heel strike
what are the 3 different muscles that insert at the medial aspect of the knee? [3]
which compartment are they all originally from? [3]
what is name for this meetin of three muscles? [3]
- Sartorius - anterior
- Gracilis - medial
- Semitendinosus - posterior
= pes anserinus !!
lower motor neurons innervate skeletal muslces (alpha-motor neurones)
where do you find the cell body of the motor unit of the NMJ? [1]
one alpha motor neuron innervates: [1]
- one muscle fibre
- a number of muscle fibres
where do you find the cell body of the motor unit of the NMJ? [1]
ventral (anterior) horn of the spinal cord
one alpha motor neuron innervates: [1]
- one muscle fibre
- *- a number of muscle fibres:** forms the motor end plate (presynaptic NMJ)
reflex test of patella: tests which nerve? [1] & which spinal segments[1]
reflex test of patella: tests femoral nerve and spinal segments L2-L4
causes contraction of quads
whats it called when have a small q angle?
whats it called when you have a large q angle?
which condyle does this cause increased presssure on for small q [1] / large q [1]?
whats it called when have a small q angle: genu varum - medial condyle
whats it called when you have a large q angle: genu valgum - lateral condyle
what is the Q line?
where is at a line between? [2]
what s the angle in men? (compared to vertical) [1]
whats the angle in women? (compared to vertical) [1]
Q line: asis –> centre of patella
what s the angle in men: 14 degress
whats the angle in women: 17 degrees
what are the two types of NMJ blockers [2] explain them
What are the two types of NMJ blockers [2]:
1. D tubocuraine: non-depolarising muscle relaxant
blocks the nicotonic Ach-R & prevents AP occuring
- Acetylcholinesterase inhibitor works as an antidote to it
- *2. depolarisng muscle relaxant**
- stimulate Ach-R like Ach and activate muscle (muscle twitch)
- but **do not detach: no more Ach can bind (paralysis)
- even if membrane is repolarised (from Na channels / NaKATPase), the drug causes it to bedesensitised**
- but breaks down after a while, so not perm. paraylses
Where do you find:
L type calcium channels [2]
N type calcium channels [1]
L type calcium channels [2]
heart
vascular smooth muscle
N type calcium channels [1]
pre-synaptic terminals - very close to the vesicles
