D. controlled cell suicide
The forest ecosystem is characterized by a large amount of trees, animals, and water, while the desert has a limited amount of species.
The answer is A. resonance. A resonant frequency means a natural frequency which is a part of vibration made by the physical parameters of any vibrating object. A vibrating object will get the resonant frequency from complex excitation and would vibrate.
The right and left ventricles are responsible for pumping blood while the right and left atria are responsible for receiving blood. These are the four main chambers of the heart that are responsible for transporting oxygenated blood within the body.
