Final answer:
A person with alopecia experiences hair loss (option d), which can affect the body's homeostasis by compromising protection from elements and sensory functions. Understanding the role of hair in the body is essential in recognizing the impact of this condition.
Step-by-step explanation:
Alopecia and Hair Loss
The correct answer to the question 'A person with alopecia has' is d. hair loss. Alopecia is a condition characterized by hair loss from the scalp and potentially other parts of the body. It can be the result of various factors, including genetic predisposition, autoimmune responses, certain medical treatments, or physical stressors. Hair plays several key roles in the body, including protection from UV radiation, insulation against cold, and aiding in the sense of touch. The absence of hair therefore can disturb the body's homeostasis by affecting these functions.
While hair loss itself is not typically harmful to physical health, it can have significant psychological and social impacts. It does not imply a lack of protein in the diet, and it is not directly associated with lice infestation or excessive sweat gland activity. Further, alopecia does not necessarily indicate exposure to conditions like radiation, which can also result in hair loss at higher doses. Understanding the function of hair in homeostasis and the implications of its loss is part of the biology curriculum that often covers the integumentary system, which includes skin, hair, and nails.