C4 photosynthesis

The question then is how the same neurons convey two different sorts of information. The answer is that motor giants are capable of generating two types of action potentials, small/slow calcium spikes and large/fast sodium spikes, depending on the degree of depolarization it receives. As opposed to the input from the ring giant, the input from the pacemaker is too low to trigger the sodium spikes, thus only inducing slow swimming. In addition to speed control, Aglantha can steer the direction of swimming by changing the shape of the bell opening, the velum. Many Hydrozoa species, including Aglantha, can move individual tentacles to deliver captured prey to the mouth, which requires coordinated directional movement of a tentacle, velum, and manubrium.