Synaptic Transition and Neuromuscular

Question 1

Local anesthetics and how they work

Answer 1

CAINE
Procain, Lidocaine, Novacaine, Cocaine
they all bind to voltage gated Na+ channels and block action potentials from being sent to CNS

cant come from external to CNS

Question 2

Neurotoxins

Answer 2

TTX
bind to Na+ channels irreversibly

they do not unbind

OVERDOSE

block channels and you die from asphyxiation

no action potentials to drive breathing, digestion

Question 3

Post synaptic potentials channels explained

excitatory and inhibitory

acronyms

Answer 3

Neurotransmitters bind to ligand gated ion channels

glutamatergic synapse is the most common excitatory synapse in the nervous system. Allows Na+ into cell which depolarizes post synaptic cell and continues action potential

EPSP

GABAergic synapse most common inhibitory synapse. Opens and allows Cl- into post synaptic neuron which makes inside more negative and further from action potential

IPSP

Question 4

Quick rundown of synapse anatomy

EPSP and IPSP together diagram

Answer 4

Neuro release- Receptors bind- IOn channels open or close- current flow- postsynaptic potential changes- postsynaptic cells excited or inhibited- SUMMATION

Post synaptic currents travel into the cell body where they sum together, if threshold voltage is crossed, action potential is initiated

Question 5

Neuromuscular junction

which neurons

how are they distributed

Answer 5

synapses between motor neurons and muscle fibres, how the CNS and PNS controls muscle contractions

Alpha motor neurons connect to a group of muscle fibres

distributed throughout the whole muscle to deliver same message everywhere

Question 6

how many synapses in neuromuscular junction

what receptor?

voltage decrease along a muscle

Answer 6

1. multiple and they are folded for increased surface area
2. Acetylcholine receptor- ACh
3. ACh bind to sites in postsynaptic cell of neuromuscular junction.
4. ACh depolarizes the muscle cell by flowing more Na+ in and K+ out but more Na+ making postsynaptic cell more positive and continuing action potential
5. Muscle fibres have action potentials occur down their entire length so voltage doesn’t decrease further from insertion