Answer: B) Myogenic heart Explanation: Hearts are of several types. In some invertebrates the heart is simulated by the nervous system to do its work. Such hearts are called Neurogenic hearts. The Human heart is myogenic. i.e, it recieves the stimuli for contraction from the muscular node called sinu-auricular node or pace maker.

Answer: A) Sulphur dioxide Explanation: Air pollutants are solid particles, gases, and liquid droplets in the air that can adversely affect ecosystems and the health of humans.   Major ambient air pollutants include toxic metals, polycyclic aromatic hydrocarbons, benzene, particulate matter (PM), nitrogen oxides, sulfur oxides, carbon monoxide, and ozone. Power plants, factories, and vehicle and air traffic are the most important anthropogenic sources of air pollution.   In addition, natural sources such as wildfires and volcanic activity contribute to ambient air pollution.