Pennsylvania Cosmetology Practice Exam

Physiology is the study of the functions and activities performed by body structures. This involves understanding how different body systems and organs work together to maintain homeostasis. Option A, the study of hair growth, is incorrect because that would fall under the category of dermatology or trichology. Option B, the study of cell division, is incorrect because that would fall under the category of cell biology or genetics. Option C, the study of the structure of body organs, is incorrect because that would fall under the category of anatomy. Therefore, D is the most accurate option describing the field of physiology.