Lecture 1 - Thurday Jan 9

Question 1

What is teh funfamental functional unti of contraction?

Answer 1

motor unit

Question 2

what is a motor unit

Answer 2

alpha motur neurona nd all the skeletal msucles fibres inn by its axon

Question 3

Force is controlled by waht 2 aspecs?

Answer 3

Frequency of activation/rate coding (MU discharfe rate)
altering # of actie MUs (de/re cruitment)

Essentially Frquency + # of MU

Question 4

where do excitatotry pstsynaptic ptenitls summate to generate an action potential?

Answer 4

axon hillock

Question 5

what animal twitched when struck w electicity acoridn glavani and what did this oppse?

Answer 5

msules of dead frogs - objected to animal electric fluid

Question 6

what does myelination do?

Answer 6

insulates axons + prevents movement of ions ( na+ and k+)

Question 7

motor neuron ap: msucle fibre potrntial = ___ ratio

Answer 7

1:1

Question 8

2 benefits to saltatory conduction/myelination

Answer 8

!) increase conduction velocity without a change in axon diamete
2) reduce emtabolic cost since only smalls egments need Na+/K+ pump to restore memrabn potential

Question 9

what is the safety factor of acH

Answer 9

3-5x is relseased for msucle fibre action potential

Question 10

what is the example of a neurosculat blocker and what does it do?

Answer 10

Curare - prevents Ach from bindinf to receptor so msucle fibres cannot generate action potential

Question 11

what prevents the release of Ach?

Answer 11

botox (botulinujm toxin)

Question 12

what is botulism and what causes it?

Answer 12

botox - paralyze all msucles liek respiratort

Question 13

how does botox act

Answer 13

prevents release of ACH by destroying SNARE proteins which release Ach therfore vesicles cannot release Ach

Question 14

what proteins bidn to membran to release Ach and what toxin rpevents this?

Answer 14

botox/botulinum toxin

Question 15

type I = ___MN innervates ___ msucle fibre froming __ MU

Answer 15

slow, slow oxidative forming slow MU

Question 16

type IIa = ___MN which inn. ___ msucle fibre forming ___ MU

Answer 16

fatirgue resistant MN, fast oxidative glycoltyic (FOG), FR MU

Question 17

type IIx = ____ MN inn___ msucle fibres fo

Answer 17

Fast fatiguable MN, glycolytic MF, formimg FF MU

Question 18

force modualtion in a twitch by?

Answer 18

of recruited MUs (soze principle_
Rate coding (discharge rate of ap)

Question 19

increasing firing rate does what to a msucle twitch?

Answer 19

summation to acheive tetanus