help with nuerotoxins question

list some of the similarities and differences of Tetrodotoxin, Sarin & Cobra venom
 i am suppose to make a table with the  similarities and differences of each toxin, this is what i got so far but 
i am not sure if it's right


also  Why does snake venom coagulate blood??


similarities

Tetrodotoxin

1.   Affect the nervous system
2.   Cause death
3.   Affect the neurons


Sarin

1.   Affect the nervous system
2.   Cause death
3.   Affect the neurons


Cobra venom

1.   Affect the nervous system
2.   Cause death
3.   Affect the neurons




Differences


Tetrodotoxin

   Block  〖Na〗^+ voltage channels
 



Sarin

1.   Acts on the cholinesterase, inhibiting it
2.   Cause build up of cholinesterase enzyme, causing muscles contract uncontrollably


Cobra venom

1.   Cause blood coagulate



are there anymore? & is this correct so far?




thank you.