The Role Of The Axon In The Sciatic Nerve
The diameter, number of axons in the sciatic nerve, speed of transmission and degree of myelination can all have an effect on the sciatic nerve and therefore the peak contractile force of B. Marinus. The diameter of the axon in the sciatic nerve would impact how fast the action potential is conceived down the axon to the synaptic cleft and muscle (Firmin, L. 2014). If one of the toads had a smaller axon diameter it would allow for resistance to movement to occur due to friction. The diameter of the axon in the sciatic nerve would therefore cause the peak contractile force to be reached at different strengths and time.
The number of axons in the sciatic nerve can play a large role when comparing different peak contractile forces of B. Marinus.
The number of axons determines how strong the action potential can be and therefore how strong the peak contractile force. If there are fewer axons in one toad and no demyelination or restriction occurs, then the toad with the most axons will have a larger peak contractile force (Firmin, L. 2014). Like the diameter, the speed of transmission down the axon will determine how fast the muscle is excited and to what extent. This can cause one of the toads to differ as a slow transmission speed as this will cause the action potential to reach the muscle fibre much slower and thus contract slower.
Table 1 displays the alternate group 2 having a maximum contraction force of 459mN at 0.5V whereas the original experiment group had a maximum contractile peak of 644.67mN at 0.3V. The maximum peak contractile force for the two groups was significantly different and at different stimulus strengths. The original experimental group had a higher force at lower stimulus strength when compared to alternate group 2. These results can be explained by the effect diameter, number of axons and speed of transmission down the sciatic nerve.
Lastly, the degree of myelination will indefinitely affect the peak contractile force of different toads. Demyelination causes action potentials to transmit down the axon at a much slower rate due to resistance and the affected insulating layer of Schwann cells. As stated in Myelination at a glance, “a demyelinated squid axon needs to be 500 nanometres in diameter to conduct action potentials at the same velocity as a myelinated 10 nanometre frog axon”. Therefore, the differences in the comparative analysis can be explained the biological reasons above (Snaidero, N. Simons, M. (2014).
The number of axons in the sciatic nerve can play a large role when comparing different peak contractile forces of B. Marinus.
The number of axons determines how strong the action potential can be and therefore how strong the peak contractile force. If there are fewer axons in one toad and no demyelination or restriction occurs, then the toad with the most axons will have a larger peak contractile force (Firmin, L. 2014). Like the diameter, the speed of transmission down the axon will determine how fast the muscle is excited and to what extent. This can cause one of the toads to differ as a slow transmission speed as this will cause the action potential to reach the muscle fibre much slower and thus contract slower.
Table 1 displays the alternate group 2 having a maximum contraction force of 459mN at 0.5V whereas the original experiment group had a maximum contractile peak of 644.67mN at 0.3V. The maximum peak contractile force for the two groups was significantly different and at different stimulus strengths. The original experimental group had a higher force at lower stimulus strength when compared to alternate group 2. These results can be explained by the effect diameter, number of axons and speed of transmission down the sciatic nerve.
Lastly, the degree of myelination will indefinitely affect the peak contractile force of different toads. Demyelination causes action potentials to transmit down the axon at a much slower rate due to resistance and the affected insulating layer of Schwann cells. As stated in Myelination at a glance, “a demyelinated squid axon needs to be 500 nanometres in diameter to conduct action potentials at the same velocity as a myelinated 10 nanometre frog axon”. Therefore, the differences in the comparative analysis can be explained the biological reasons above (Snaidero, N. Simons, M. (2014).