The nervous system and cardiovascular system
Tachycardia, also known as a high heart rate, is a term used to refer to a pulse rate greater than 100 beats per minute and may be a reflex when the body senses a fall in blood pressure.
Commonly some of the used medication may cause the unwanted side effect of tachycardia and low blood pressure. These may include some medicines like calcium channel blockers, diuretics, and various types of antidepressants.
Answer:
Incidence unchanged, prevalence increases.
Explanation:
Disease can be caused by the pathogens like virus, bacteria, fungi and plasmodium. The infection fro the disease also depends on the immunity of the individuals.
Discovery of the drug requires different experiment and observations. The drug that prevents the mortality but not able to cure the disease. This do not change the disease incidence but might not able to the increase in the prevalence of the disease.
Thus, the answer is incidence unchanged, prevalence increases.
The thyroid gland... I think
The Answer Would Be Pulling A Rope In A Tug-Of-War.