Non-rapid eye movement sleep activation occurs during NREM that is comparable to the type that occurs during REM. It is this sub-cortical activation that results in dreaming during the NREM stage during the morning hours. During non-REM sleep, the tonic drive to most respiratory muscles of the upper airway is inhibited. This has two consequences: However, because the diaphragm is largely driven by the autonomous system, it is relatively spared of non-REM inhibition. As such, the suction pressures it generates stay the same. This narrows the upper airway during sleep, increasing resistance and making airflow through the upper airway turbulent and noisy. For example,
Rapid plant movement Darwin published "The Power of Movement in Plants", his second-to-last work before his death. Plants that are able to rapidly move their leaves or their leaflets in response to mechanical stimulation such as touch (thigmonasty): Plants that move their leafs or leaflets at speeds rapid enough to be perceivable with the naked eye: Rapid plant movement Rapid plant movement encompasses movement in plant structures occurring over a very short period, usually under one second. For example, the Venus flytrap closes its trap in about 100 milliseconds. The dogwood bunchberry's flower opens its petals and fires pollen in less than 0.5