plantbabz17 plantbabz17 04-03-2021 Biology contestada I just don't know what each one is Stimulus: Ca2+ ion levels in blood are too low •Sensor: •Control center: •Effector and action(s): •Negative feedback: •Stimulus: Ca2+ ion levels in blood are too high •Sensor: •Control center: •Effector and action(s): •Negative feedback: